I really do love this channel, so it's with a bit of reservation that I made a video response to this. Ultimately, I do not want to see people painting their intercoolers black for unjustified reasons (Don't do it!). You can check out the video on my channel, if you're interested.
Engineering Explained I watched your vid and then came here via your link. I don't think they did anything wrong, but they're interpreting the results in an incorrect way. They hinted at it in the end but seemed to come to the conclusion to paint all of them, regardless of application. In drag racing, I think this would be perfect (as stated in this vid). However, based on your vid and the info I learned here, painting one in any car that's not drag racing would be a mistake as air is constantly flowing over it when it's being used so the -3% difference is significant.
Dani2wheels Yep, I agree. I think the test was great, and the data good, but ultimately the wrong conclusion achieved. I still would disagree on the drag car scenario. Once the drag car is moving (at all), it's getting less cooling via radiation, which at 50 mph (a low speed) the amount of convection is incredibly significant. As the car reaches higher speeds, the temp drop becomes even more significant with more convection. The small amount of radiation the intercooler gives off (and assuming there are no heat sources radiating heat onto the intercooler - the sun, exhaust manifold, turbo, etc.) will be super insignificant in comparison to the amount of heat an intercooler can disperse via convection at 100+ mph.
Engineering Explained As far as drag racing, I think you'd just have to run some tests and gather much more info. The question is: will the increased cooling while stationary offset the 3% loss at speed? And, is it even -3% at speed? It could be an exponential loss as speed increases because aerodynamic drag increases exponentially which could cause friction and heat on the paint to make it far more than -3% over unpainted. It's definitely curious test results that MCM have gotten, though, but it begs more testing if you're serious about performance. And, like you, I wouldn't recommend anyone short of an F1 team to seriously consider painting an intercooler.
Engineering Explained I also agree with your video. Including the heat transfer coefficient will only proof, that it would in fact transfer heat through the material slower, than a cooler without paint.
They would only be able to do it at a drag strip and only "feel" the difference which could be hard when they know they should. If they go to a dyno they will use a fan and then there is only a 0,008% gain. (373,15K/370,15K). Even at a standstill there is still only 13% (350,15K/311,15K) difference with quickly becomes 0,008%. It probably won't feel faster but it might save some wear and tare on the components of the engine.
No, it wouldn't have made a difference, with air flow (ie. dyno or pull on street or drag) there's very little difference - they proved that. The thing is, when you're at the drag strip all staged up (idling) at a 95*F day and you're waiting for the other person to stage up, your intercooler is pissing that heat out of there like nobody's business, so you'll have more power out of the hole for sure. Though once you're moving pretty good (airflow) it won't make as much. So a dyno result won't show much, but it's obviously what you want.
MrSlowestD16 not true as your turbo is not creating pressurised air while you are idling. your temps post turbo but pre intercooler would not be hot at all
But radiators are only meant to reduce heat via convection. That is why engines in moving cars with airflow are cooler than engines in sitting traffic. That is also why there are fans on radiators. The black radiator actually performed worst in the fan scenario, which is the scenario that all cars actively employ. Which means: If you have a radiator to just sit there, paint it black; If you have a radiator in a windy environment (like a car), keep it silver.
Paint is an insulator. The results you see are purely down to the paint drying (drawing out heat) . Do the same test after a few weeks when paint is fully cured and you will see why this is a bad idea.
Absolutely the wrong conclusion. They were so focused on the huge change with no airflow that they ignored the FACT that the bare aluminum one performed better by 3% with airflow. When do you need your intercooler to perform better - when you're at a stoplight and the turbo isn't providing any boost, or when you're moving and the turbo is boosting and adding heat? If you care at all about its efficiency without airflow you understand nothing about boosted engines. 3% better heat absorption can mean the difference between detonation or not.
You also have to consider the test environment. They have a room space that is not at a constant temp. If it's an open garage for example, you may also have a slight breeze that will influence the result. Typically with data analysis you are looking at large trends and significant differences. Now to know what's significant, you need to run several tests and understand the sense of scale.
he literally says "the amount of heat lost to radiation is probably insignificant compared to the amount of heat that's lost to convection with the air flowing through it." @10:54 His point being when you're sitting still, there's no airflow, so no convection just radiation, so the black paint DOES make a difference. EXCEPT that your intercooler probably has a fan on it, to make sure there IS air flow, because it IS reliant on convection, radiation is in his own words "probably insignificant."
Yes, the paint made the the intercooler a better radiator and a worse convector, great if the application involves mostly radiation, but in the real world of moving air it performed worse overall because of the insulation.
The amount of heat gained from radiation is a significant factor as well. In a garage the intercooler is not receiving much heat. Close to a hot. engine and blazing hot turbo charger and emissivity is working against you. Emissivity is a 2 way street. Good at sending means good at receiving. This is a great show, but here they were not correct. If you really want a black intercooler, get one anodized.
Engineering Explained - Mythbusting Mighty Car Mods. An Engineer who understands science talking about why they are wrong. MCM - Two guys who have mechanic friends talk about what they think. Yeah I'll go with the engineer, as an engineer myself.
White blocks heat transfer and black increases heat transfer = Undisputable law. But a coating of paint reduces the heat transfer. However anodizing becomes a component of the aluminum and stabilizes and makes aluminum more durable. And black anodizing is available.
This mod was used on my Ford Escort RS turbo in the late 80's AND YES IT WORKS TURBO systems motorsport who were one of the UK's top ford tuners in the day and Colins performance both recomended this mod and its cheap easy to do and works.! Also adding a deflector plate helps to by diverting more cold air to it! "Forget the doubters this is real" ( If there are any april fools here its the people who didnt paint theirs! lmao.) !
An intercooler works through convection not radiation. they seem to be ignoring the results from having air passing through the intercooler. However that's what they should really be concentrating on as the vehicle that the intercooler is fitted to is designed to be moving.
Love your channel. And I applaud this scientific testing. But I think you have flawed results. The painted intercooler is covered in fresh paint. And that paint is still evaporating it's solvents. So it is not just giving off heat by radiation. It is also evaporating, (just like if you had used a water spray) and of course there is some airflow due to convection. Given enough time to cure, a week, a month... the advantage of the fresh paint will disappear. And the 3% gap seen with airflow will likely widen due to the insulation effect of the paint. A better test would be 2 identical intercoolers from the same factory, one bright shiny chrome on the outside, one anodized black.
9:16 Plain aluminum intercoolers emit colder air than black intercoolers WHEN THE CAR IS MOVING. Since we want cars to move, and colder air is better, your conclusion is most puzzling.
If painting the intercooler black did anything, I would think that it would make less power since black colors absorb heat as opposed to reflecting it? So black would only really be wanted if you're going for more of a stealth look instead of a nice shiny intercooler. :)
Black absorbs solar heat more than any other color, but the intercooler isn't going to be mounted in direct sunlight so its solar radiation heatsoak vs. the larger cooling area benefit is going to be negligible. Lol
actually that black gets hotter is not true, only a myth that has been busted, on the other hand the paint in itself obserbe heat better then the bere metal so there is maybe a minor difference but not so big difference that the engine would notice.
Years ago my friends and I did a simular test with two identical IC's but we powder coated one instead of paint. The powder coat was a plain powder no ceramics and was black in color. From what we found the powder coated IC had a hotter discharge temp being almost 40 degrees hotter then the non powder coated IC. There's obviously a big difference between spray paint and powder coatings and the PC seemed to actually prevent the dissipation of heat throught the IC. Not sure if ceramic PC would have the same effect or not. Good to know that regular black spray paint actually helps. After our tests we kinda assumed paint would have the same effect as PC but just not as much.
I actually work at s powder coating shop ... This is something I must ask my boss on whether ceramic coating or powder coating work better to cool down metals ..
I actually work at s powder coating shop ... This is something I must ask my boss on whether ceramic coating or powder coating work better to cool down metals ..
Emissivity is a 2 way street. The ability to emit heat via radiation is always equal to the ability to absorb heat. A radiator or intercooler in an engine bay emitting heat via radiation can just as easily receive heat from the engine, turbo, or other radiators. The heat it radiates may be reflected back by metal body panels and structural components, or may simply heat those up. In the test in the video, the intercooler is not close to a hot engine, radiator AC radiator, or oil cooler. In the test in this video the black intercooler is 3% less efficient than the silver with airflow, even with all those hot components around it. We are all free to paint the radiators and intercoolers of our cars black. Heck, pull your refrigerator away from the wall, and spray it's radiator black, then hit the out door AC unit of your home. But you'll find efficiency drops, rather than improves.
since when radiator of a refrigerator is something other than black? they work with both natural convection and radiation. Your understanding is unrelevant. And your example. You can see efficiency gains because convection is better than radiation in MOST cases. Even a smallest wind can make you dumb.
@@sametbayboru8965 Most refrigerator radiator are unpainted silver/grey. The little college ones with an exposed radiator in the back are painted black because they will be handled and oils from fingers are bad for the finish. So are most air conditioners, car radiators, intercoolers, oil coolers, etc etc. Silver/grey. I'd post some photos, but extreme losers will then tag the photos as spam and the post disappears. Loosers....
Anodizing an IC any color will make it perform better than the stock bare aluminum. This is because the anodizing has a slightly rough surface which provides more surface area to dissipate heat. However, painting an IC black will insulate the IC because it makes it smoother which will decrease its efficiency when air is moving over it. When they had air flowing through them, the shiny had a 100deg difference where the black had 97deg. That right there is the paint insulating the IC and where anodizing would out perform. In terms of when there is no air flowing through, anodized and painted should have a similar efficiency based on emmisive properties when painted black, however, the anodizing will still have the extra surface area to dissipate heat along with the emissive properties (taking the lead over paint). Basically what im trying to say here, is spend the money to get it anodized (maybe 100$) and have the double benefit of more surface area and the black emmisive properties so you gain when in stale air and when moving. If you cant anodize it, it had better be painted black because all other lighter colors don't have the same emissive properties. Id like to see MCM anodize an IC black and see what results they get
You should dino a car with a silver intercooler and then change it for the same black painted one. Just so we can see if there is a HP difference and a valid reason to spray it black.
With most things related to a car, this may not actually turn out to be a tangible effect, however it should prolong the life of your turbo with better cooling and theoretically, a colder turbo should mean it spools faster, but there are some many other variables in a car that it probably won't show us much of a difference.
That theory doesn't make sense... The IC is after the turbo, so painting the IC black will have no effect upon the turbo... It will push the same amount of air with a painted or un-painted intercooler....
97 deg C reduction (with black paint) is WORSE than 100 deg reduction (with bare aluminum). Furthermore, under what scenario will the engine/ECU go into boost (and require cooler intake air temp) while there is no airflow across the Charge Air Cooler fins? Finally, a CAC sheds intake air heat via convection, not radiation. Black paint would affect radiant heat transfer, not convective. Save your spray can for something else. P.S. Props for using sensors and collecting data (into Matlab as well). It's just that the conclusions drawn are not very sound.
"a CAC sheds intake air heat via convection, not radiation" Yeah.... No. It sheds heath through radiation/advection to the air flowing outside the ducts / the water then the fins, then the ducts. Please don't forget that there is a wall of material that is not subject to convection _because it is solid_ .
Actually, it sheds heat via conduction and radiation. Heat conduction, also called diffusion, is the direct microscopic exchange of kinetic energy of particles through the boundary between two systems. When there is no airflow through the radiator by advection, the air particles "trapped" in the heat exchanger fins heat up so those particle temperatures move towards equilibrium with the particle temperatures in the skin of the heat exchanger, which is moving towards equilibrium with the temperatures of the air particles inside the heat exchanger. These "trapped" particles don't stay trapped. Convection causes the less dense air particles to rise out of the fin gaps, being replaced by cooler, denser air particles. Advection, or pushing of air horizontally through the heat exchanger fins, allows the air heating up through conduction and radiation to be replaced more quickly by cool air, allowing for a larger temperature differential between the particles in the heat exchanger skin/fins and the outside air, allowing for a higher conduction rate. One thing to remember is that radiation works both ways. Every fin is emitting radiation towards its neighbour, and every fin is receiving radiation from its neighbour. Some of that radiation is being absorbed by the air. Increasing the emissivity by painting the heat exchanger black allows more energy to be emitted as radiation, increasing the amount the air particles are warmed, but decreases the amount of conduction as a result of the paint acting as an insulator. Also, the engine is a massive radiation source. If the engine is a 150°C heat source (as an arbitrary figure) and the heat exchanger is a 100°C heat source, net effect will be heat exchanger receiving more radiated energy from the engine than it radiates towards the engine. A low-emissivity heat exchanger will be a bonus in this case, as it reduces the 'heat soak' from the motor. It would appear from this experiment that conduction occurs at a higher rate than radiation with an unpainted heat exchanger, with the two forms of heat energy transfer much more closely matched when the heat exchanger is painted black. Given that advection will occur when the vehicle is moving, therefore generating boost, therefore requiring charge cooling, I would go with not painting, or applying a coating with high levels of emissivity AND conductivity. Black anodising sounds like the business.
black is worse. First graphic proved it in their own video. with air flowing silver gave 100 C difference black one 97 C difference. That 3% better as silver. Intercoolers are designed to use convection not radiation. Black will also pick up radiated heat from other parts of the engine compartment too not just sun light.
If you're considering the *Difference* between the air temperatures in and out of the intercoolers, then doesn't that means that the higher it is, the better? Therefore without airflow, the black wins (due to emissivity) but with airflow the non-painted one wins, due to convection. and since the vehicle will typically be in motion, painting it black will be disadvantageous just sayn...
The one with paint won because of wet paint. Not because of emissivity. Evaportation is great and is why many systems sprits the intercooler with water.
@@BespokePowerhouse The sun is 93 Million miles away, how about the flaming hot turbo, or the engine block? You want your intercoolers and radiators shiny and reflective. Bounce that heat away.
Marty and Moog, your conclusion should have been: Don't paint your intercooler, or radiator for that matter, but add a small electric fan to it for when you are in traffic or at the drags. much simpler than painting it. The paint made the intercooler 3% worse with air moving over it. cheers fellas
i think if you consider that behind the intercooler would be a hot engine, then the black maybe will absorb that heat and will make it less efficient, also the paint is an extra layer of insulation, by its own and stationary it is better but in the car i am not so sure. My thought is to have the front side black (maybe not so good if direct sunlight hits it but does the job) and the side close to the engine heat a reflective silver
Huh? Why don't you speak with proper terminology? Convection and radiation. Black does indeed absorb radiative heat, which a hot engine would definitely be emitting, depending on its outer coating. It should either be polished to a mirror surface or coated with another metal to behave as such.
Black painting of intercooler/ radiators etc is done purely for looks. It will in fact reduce the efficiency of intercooler/ heat exchanger. As it did by 3% in your case. Love your videos btw.
I wonder what kind of difference would be made if, instead of using paint, the intercooler was anodised and dyed black during this process. In theory, by having the black _in_ the aluminium instead of as a coating _on_ the aluminium, you should be able to achieve the higher temperature differential of the black unit without any insulating effect.
I guess the paint didnt fully dry (if you wait a couple days or maybe weeks) . Because of that some of the paint would evaporate and take a little bit of heat with it. Im not sure tho...
What happens when the intercooler is sitting next to something hot though - like a radiator or AC rad for instance? Would love to see what happens on a dyno.
A dyno can't simulate the actual situation that there would be an actual benefit of the black paint as the car is mostly indoors and with a huge fan blowing air regardless of the car speed. Moreover running cooler wouldn't produce more HP. You would need a new tune to benefit from the engine's improved tolerance.
n00b1n4t0r The fan on a dyno can be turned off to simulate sitting in traffic so it would be a decent test. Also every turbo car I have heard of in the last 15+ years has knock sensors. They adjust timing according to when detonation starts (well it goes off a count of how many det's occur). Basically if the intercooler keeps things cooler the ecu can feed in more fuel and advance the timing more. It will definitely make more power.
It might be 8 years later but it seems you guys were correct in your conclusions. What has been falsely banded about here and via Engineering Explained is that intercoolers and on the same principals, radiators, work via convection only. This assumption is flawed and incomplete. They lose heat via both modes. However as air flow is introduced the convection component of the total heat loss of the system increases for both the painted and unpainted coolers in relation to their radiant heat loss component and so the insulating effect of the paint marginally decreases the system efficiency (97%). At the same time the converse is also true in that with zero flow (static) air the radiant component of the total heat loss increases by which you demonstrated the black painted one had a significant improvement over the shiny bare Al one. If intercoolers and radiators worked via convection only, every working ICE powered vehicle on earth would have massive over heating issues. That radiant element of total heat loss can be felt by simply putting your hand near a rad or intercooler while the vehicle is at rest. Exalting thermodynamic principals to a religious level like holy scripture is folly even more so when rudamentary flaws in basic assumptions are made by those who Explain Engineering and claim to 'know better'. At the very least an apology is due to you guys from you know who :)
the reason why you paint the radiator black is to even out the heat distribution. if they ever do this agian. i think a Infrared camra would be great addition to the test instead of just sensors.
I clicked this video thinking it was BS after watching it you guys changed my mind. I think I am going to paint my radiator and oil cooler black . Great vid guys.
I just spray painted my computer's heatsink and CPU itself (used that as thermal paste, just apply the heatsink while the CPU is wet) and nothing is working. HALP!
Fridge condenser radiator is black to help disipate heat. Transformers are painted often in black, to help disipate heat ... Nos CPU coolers man, that is not fashion ... let this weird look for HP
38911bytefree I once had an HP laptop that used a painted black heatsink. Unfortunately the thermal paste system is shit. They put tinfoil on the heatsink then put thermal paste there then put it on the heatsink! All the crap dried out and I had to totally scratch it up. Right now the fucking memory sockets/controller don't work properly it made the fucking laptop USELESS!
9:01 from 100°C to 97°C temperature difference is not a negligible improvement, it is a small worsening. And with higher windspeeds, which are likely to occur in real circumstances, the worsening will be even greater. So your conclusion of does no harm is plain wrong.
Did you just say "small worsening"? ... and then the "worsening" would be even greater? How about small disadvantage? I would like to point out they said the disadvantages are outweighed by the benefits when sitting still. Also, you're missing the point. They clearly say that there would be an advantage IN traffic and AT the drag strip. Basically painting it black would help prevent the intercooler from becoming overly heat soaked so when you hit the gas once traffic clears or the Christmas tree turns green you could get some cooler air than if it wasn't painted. Furthermore. 3* isn't really a huge deal when it comes to intake temperature however, when you're sitting at a stop a difference of over 40* is a HUGE difference.
+Dan W First, it will be more than 3° because normally you drive faster than this fan blows. Second, when standing still, your turbo isn't really working that much so you won't "heatsoak" your intercooler anyways.
I have some questions. First what about other colors. Does the color matter? Second, how long after you painted, did you do the test? You might have had volatiles left in the paint which throw off the test. Evaporating paint emissions could also effect heat transfer.
1. Read about isolation (in this example it is the black paint) 2. Read about thermal conduction. 3. Even in this video 9:13 "with airflow" (which is the more significant for actually DRIVING a car) you have a bigger delta between in- and output on the non-painted intercooler. 4. You would lose (not noticeable) HP when you paint it black but never gain power.. 5. Black paint would only be an asset on an intercooler if you want to keep your car unobtrusively.
+1 on the anodizing. That is what i used on my Diesel intercooler. Dropped my intake temps by almost 60 deg in real world use. I just did it to look more discrete, And black looks sick!
5:05 he says "painting it black changes emissivity and that has nothing to do with airflow".. but an intercooler literally works by cooling flowing air :/
He is talking about the air flowing across the intercooler not the air flowing through it. He is saying that air flowing across the intercooler or not flowing across it has nothing to do with difference of the amount of radiation that can be released because of the color change.
Yeah and the result was that it was 3 degrees less efficient but they completely ignored that. The point is the emissivity doesn't matter because the intercooler's job is to cool the air that's flowing through it. They did the test and the black one was clearly less efficient.
@@chubzdon1 emissivity does matter. If your intercooler is near a hot engine or worse a turbo, you want it bright, shiny and reflecting away radiant heat. IF YOU ARE COOLING A HAIRDRYER IN A GARGE, BLACK IS GOOD!
So they conclude that the black is better dispite the alloy one actually cooling the air better when doing the test it was designed to do? Or have I got that wrong
+stephen reed You are spot on. They think because black wins standing still, it's best. But a car does not stand still! IN those circumstances, black loses. They proved it, but still Electronical Stig made the wrong conclusion. Funny!
It loses because intercoolers work through direct conduction to the cool air blowing past the exterior surface, not the piddly amount of radiative cooling you might get with a different color paint. Paint acts as an insulator and reduces the efficiency of the bare aluminum metal's excellent thermal conduction. Even if the car is sitting still, that tiny amount of extra radiative cooling will not benefit you once a significant mass of hot compressed air starts flowing through that intercooler, and the insulating paint will only slow down that heat from getting to the outside surface of the fins to be conducted away by ambient air.
makes sense. most radiators i have dealt with on my cars as well as friends cars have all had the black paint layer on them.. jeeps etc. i always thought it was a protective coating more for preventing the oxidation of the aluminum and from damage from road debris like sand as well as aesthetics on the front end of such exposed openings. so for it to improve it capacity to radiate heat away brings the whole thing full circle. and radiant heat is radiant heat so doesn't matter if it hot air or hot water flowing through, the black coating would help. but i will say it probably does matter what type of black paint is used as some paints would insulate more than others. like the coatings used on exhausts that contain ceramics to actually trap heat the same as fiberglass exhaust wraps do.
The surface treatment of the IC prior to coating, the composition of the coating, the applied thickness all play a role on whether the coating will act as a thermal insulator or conductor.
I always wondered why turbo guys leave it unpainted. This was figured out years ago with early VW mods. The polished or chromed tins around the covered oil cooler and head tins would increase engine and oil temps. Painted one's, disapated heat much faster and brought down temps considerably. They found this out to be true with radiators as well. Thanks for your experiment though.
Great experiment guys. Its pretty well controlled. Food for thought: There was likely a percentage of the paint solvent which remained until your static heating by the hair dryer. Paints typically take 24 hours to have 100% of the solvent to evaporate. The evaporating solvent has a latent heat of vaporization which pulls energy out the surface from which it evaporates. (dropping the temperature artificially low) I wager that a re-test of the same black intercooler will yield the same result for the airflow test while yeilding a smaller deltaT for the first test. Emissivity does matter, but radiation is orders of magnitude slower than convection or conduction. I am going to be a Dr. in this field, hence the science in my vids. :) Keep up the good work guys!
Its not the color at all but the top layer emissivity that effects the heat loss by radiation. If you look into it, different materials have different emissivity levels. This means that alumininium or chrome for instance has a very low emissivity value. Paint the aluminium though and NOT because of the color change but because of the top layer emissivity, heat radiation changes. Try it out: heat a chrome bar and hold your hand near it to try and feel the radiation. Now apply tape or something more heat resistent (paint...) all over the surface and redo. There will be a noticeable difference in radiation because the top layer emissivity changed. As a thermographer, I know.
Your conclusion is backwards, 100° temperature difference in inlet and outlet temperature with the bare aluminum intercooler, and 97° temperature difference in inlet and outlet temperature with the painted intercooler means that the air coming out of the painted intercooler is warmer than the air coming out of the bare aluminum intercooler. If the outlet temperature of the painted intercooler was 103° difference then it would mean that the painted intercooler was more efficient. Your test proves that a painted intercooler is less efficient than a bare aluminum intercooler, with airflow through the intercooler, which is how it is designed to work.
James Mosley you are correct. Plus, the without airflow test is irrelevant because in All situations you will be having airflow. On a dyno, street racing, race track. So the non airflow test doesn’t matter one bit EVEN IF it wasn’t backwards lol they had some good ideas but poorly executed.
@@badass1g I didn't know days where the air was still counted as airflow. No seriously, you will not have airflow ALL the time. You will have idle times, it's inevitable. Besides, the efficiency on the high end only dropped by 3C which is pretty insignificant, meanwhile you have that massive gain on the low end. Overall painting it comes out on top.
What you're seeing is three dudes who don't know the difference between radiative and convective heat loss. The intercooler is a radiator, so relies entirely on airflow through it to cool it. Painting it black just creates a slightly less conductive coating on the surface which makes it less efficient.
+Cardinal Biggles: "What you're seeing is three dudes who don't know the difference between radiative and convective heat loss. The intercooler is a radiator ..." Lol, apparently you don't either, the intercooler is *not* a radiator. (Although it is also wrongly called that in common language like your water cooling radiator which is also a convector, not a radiator)
Scientifically speaking it is also a radiator, just like every other part of a car, but calling it a radiator because of that is just meaningless. Do you call the mirrors radiators as well? Technically speaking - that is, in its designed mode of operation - the intercooler sheds 95% to 100% of the heat through convection, ergo, it should be called a convector.
the one thing that might have messed up the results is the fan is blowing at the intercooler right, and the tubing is open facing the fan. car fans do a really good job blowing air over a wide radius. my worry is, the reason why with air flow both cars were nearly the same is because there was air flow going into the tube and interfering with the outlet temp. with that said, i like the silver intercooler look, i mean comeonn. black may be awesome, but shiny silver is also pretty sweet.
Can't deny the science here. Your own experiment proves that black paint on an inter cooler is less efficient that with plain aluminum during air movement. Ever notice that the transmission cooler located at the bottom of the radiator is painted black? And that the top of the radiator is painted black? Probably to prevent rust during rain/water splash. But think about this. An aftermarket transmission cooler placed in front of the radiator cools far better than in the stock radiator. Why? Airflow.
Only slight less so. And by using much less energy by going completely fanless, just painting it black results in much better performance. I'd say that's a clear win by far for performance-to-weight ratio.
Air flow is a big part, but equally significant is the fact that the fluid cooling through a dedicated cooler is not impeded by the temp of the coolant circulating through the radiator core! The fluid temp can only drop as low as the radiators overall temp.
Very entertaining! I love a garage test lab as much as the next man. But seriously? The only thing that would convince me would be a dyno run before and after paint. So once I've fitted the intercooler to my bike, I'm leaving it yellow...
The temperature sensors monitoring heat in this video is mounted externally. paint acting an as insulator will have less heat outside. the proper way to do this test would have been to have the temperature sensors inside, where the airflow is traveling.
You guys should read up on ‘confirmation bias’. You so wanted it to work you called the test with airflow (you know the one like how a car operates) showed a negligible improvement, NO, it made it worse, sorry guys, great idea, good test, screwed up the conclusion.
I had just come across this video, so I apologize for being late to comment. What if you were to black anodize the aluminum on the intake. Would this not be a thin enough layer to still keep most of the emissivity of the aluminum yet combined with the effects of being black? Not an engineer but I am curious. Thanks.
+Robert Elmore I found data for black anodizing that said it was 200x less conductive to heat than base Al but emissivity was 20X greater. Under some conditions anodizing will transfer additional heat by radiation, but only if the surrounding surfaces are kept at a lower temperature, and you have enough cooling airflow to counter the reduction in convection due to the lower conductivity. Need to test...!
@Nybbl er Anodizing is not a coating, it's created by oxidizing the surface of aluminium. which can be dyed to any colour. Anodizing actually significantly improves the performance of electronic heat sinks by significantly increasing the surface emissivity from around .05 for bare aluminium to 0.85 The colour makes no measurable difference
Anodizing would be better than painting. But if the intercooler is in a car near a hot engine, tube and radiator, you want low emissivity, silver. For cooling hair dryers in a garage, paint works great.
Why do you always take so long to upload videos :'( one a week minimum please, I would even pay monthly for it on tv if I could! best thing ever! should be on tv. love you guys!
Will this work with Radiators as well? Reason I ask is that I've a Polo 6R 1.2TSI which has a charge air cooler that is cooled by radiator liquid passed thru a secondary radiator. I've been busting my head on how to get the IATs to drop but short of a larger radiator, I've run out of any solution which can work, UNTIL i saw this video.. please please help here :-)..
Part of the small difference between bare and black (with air flow) might be the layers of paint impeding air flow by reducing the distance between the cooling fins. I would think that if the inter-cooler was black anodized, instead of being painted, the difference would be greater. Also, the interior of the inter-cooler still being bare, when just being painted, is a factor too. An inter-cooler of black anodized aluminum (black inside & out) might show completely different results for the better. JMO. I'm surprised that you guys didn't do a dyno test too. That's what really might show whether it's worth it. Also, JMO.
This just in, MCM can you please test the following performance difference, a car with and without wheels. Whilst the car isn't driving, say at traffic lights or in my garage, the one without wheels will have a lower weight, and therefore will race faster. Right?
Important: remember that behind the intercooler will stand the radiator, which is hot. So, for better performance, the back of the intercooler should be reflective (low e), while the front should be emmissive (high e). Hence, if you're thinking abot painting yours black, do it just in the frontal area. The test these guys performed is enough to prove a point, but you gotta keep real instalation conditions in mind! Cheers
So pretty much painting the intercooler black disperses more heat through radiation, but making almost no difference under convection due to the insulating layer of paint.. so does this mean if you can somehow change the color to black without applying an extra insulating layer to the existing aluminum, then you can finally reap the benifits of it? If so then can there be a substance mixed into the aluminum at creation to change the color to black without needing an outer insulating layer? Interesting.. 40° is alot. Its the difference between driving in the summer compared to winter for turboed cars..
my only question is how can you come to the conclusion that radiation is more prevalent than convection when convection produced better cooling results in both cases?
Radiation doesn't depend on fluid movement for cooling. Essentially, radiation uses the characteristics of light (EM properties), whereas convection uses the fluid interacting with the heat source (air moving past the radiator).
right, and a car radiator (despite its epic misnomer) doesn't dissipate the majority of its energy through Radiation and so trying to focus your efforts on improving its radiation while hindering its convection is really dumb.
thermostats in cooling systems regulate temperature but just as importantly the flow rate of coolant through the radiator as it needs to be slowed down to allow the heat transfer to take place.if the coolant flows too fast (ie. if you thought removing the thermostat would help your overheating issue) the coolant passes through the radiator too fast and back into the heat of the engine thus not cooling your medium efficiently and ending up with over heating. basically you cant keep your charge air in an intercooler long enough for this whole idea to be effective so as it goes the r and d of the big car performance brands is probably why what we have is about as good as were capable of at the current time!
After cleaning dye from a flashlight where aluminum plate with soldered led touches anodized aluminum I got flashlight getting much warmer than before. I used pipe cleaner with powerful alkali. After pure aluminum was exposed added thermal paste and got a good thermal spread. Even anodized aluminum in my flashlight was bad for thermal resistance.
Really? Looking for performance differences between two colors? Now I'm a fan of MCM, watched turbos and temples like 20 times, watched every episode, so don't take me as a hater when I say this is just low quality for the channel. Ok, I got it, you are building an awesome project car, but make us wait for so long to have a tutorial on how to apply stickers and this, is just low for the MCM I love. Hope next videos are more entertaining. ..
A real MCM fan would be patient and enjoy what was released to be a 'tie over' episode. They only put it out so that they weren't inactive for too long. They have lives outside of MCM. Try to be less selfish and be happy that they are currently tackling a project bigger than they ever have for YOU and the other (perhaps truer?) MCM fans.
what if you anodized an intercooler black.... it wouldn't insulate at all but would still have the benifits of the blackness and might be more effective
I was thinking this, and I think this may be correct, however the actual importance of radiation compared to the convection and conduction of heat in the intercooler would make that an expensive and very insignificant upgrade.
It's Barney but..... for science?? but seriously I do agree I just want to see it done. the situation I think it would be really good in is stop and go traffic and keep in mind a manufacturer could easily overcome the cost by building a lot of them. so yea I agree it would be dumb for an individual to do but maybe we could convince a good manufacturer to do it if there was evidence (easy advertising) already done to support it
if you able to keep the black paint cool like keeps your car moving then the coat shouldn't matter. the extra coat will keep certain temperature along the way as you moving. its like putung a left over food in a metal container. as long the container remain the same temperature the food will stay warm.
Heat is not just from visible light. Your engine is emitting tons of non visible wavelengths (infrared) and the black inter-cooler will absorb that much ore than a silver one. Additionally, your environment is much cooler than an engine bay, so the percentage difference would be a lot less if the black did work. Your "scientific test is not well-designed an it doesn't take this these factors into account. Try doing it in an oven that approximates engine temperatures.
When you are stopped at a stop light the intercooler doesn’t have hot air blowing through it because the turbo isn’t spinning and the exhaust is cooler. It isn’t realistic to think that it will have extremely hot air going through it at a standstill.
I'd bet that they didn't wait for the paint to properly cure and during the first heat test without airflow the paint cured and offgassed, causing it to shed heat faster. This also points to why it made a negligible difference under airflow since the paint had cured.
I really do love this channel, so it's with a bit of reservation that I made a video response to this. Ultimately, I do not want to see people painting their intercoolers black for unjustified reasons (Don't do it!). You can check out the video on my channel, if you're interested.
Here's the link: Black Intercoolers - Mythbusting Mighty Car Mods
Engineering Explained I watched your vid and then came here via your link. I don't think they did anything wrong, but they're interpreting the results in an incorrect way. They hinted at it in the end but seemed to come to the conclusion to paint all of them, regardless of application. In drag racing, I think this would be perfect (as stated in this vid). However, based on your vid and the info I learned here, painting one in any car that's not drag racing would be a mistake as air is constantly flowing over it when it's being used so the -3% difference is significant.
Dani2wheels Yep, I agree. I think the test was great, and the data good, but ultimately the wrong conclusion achieved. I still would disagree on the drag car scenario. Once the drag car is moving (at all), it's getting less cooling via radiation, which at 50 mph (a low speed) the amount of convection is incredibly significant. As the car reaches higher speeds, the temp drop becomes even more significant with more convection. The small amount of radiation the intercooler gives off (and assuming there are no heat sources radiating heat onto the intercooler - the sun, exhaust manifold, turbo, etc.) will be super insignificant in comparison to the amount of heat an intercooler can disperse via convection at 100+ mph.
Engineering Explained As far as drag racing, I think you'd just have to run some tests and gather much more info. The question is: will the increased cooling while stationary offset the 3% loss at speed? And, is it even -3% at speed? It could be an exponential loss as speed increases because aerodynamic drag increases exponentially which could cause friction and heat on the paint to make it far more than -3% over unpainted. It's definitely curious test results that MCM have gotten, though, but it begs more testing if you're serious about performance. And, like you, I wouldn't recommend anyone short of an F1 team to seriously consider painting an intercooler.
Engineering Explained I also agree with your video. Including the heat transfer coefficient will only proof, that it would in fact transfer heat through the material slower, than a cooler without paint.
Loved this video. One thing i wanted to see, would be them testing it on a car to see if they feel the power change.
Can't wait for the next ep :)
Still own that sz supra? msg me ,interested buyer
They would only be able to do it at a drag strip and only "feel" the difference which could be hard when they know they should.
If they go to a dyno they will use a fan and then there is only a 0,008% gain. (373,15K/370,15K).
Even at a standstill there is still only 13% (350,15K/311,15K) difference with quickly becomes 0,008%.
It probably won't feel faster but it might save some wear and tare on the components of the engine.
No, it wouldn't have made a difference, with air flow (ie. dyno or pull on street or drag) there's very little difference - they proved that. The thing is, when you're at the drag strip all staged up (idling) at a 95*F day and you're waiting for the other person to stage up, your intercooler is pissing that heat out of there like nobody's business, so you'll have more power out of the hole for sure.
Though once you're moving pretty good (airflow) it won't make as much. So a dyno result won't show much, but it's obviously what you want.
MrSlowestD16 not true as your turbo is not creating pressurised air while you are idling. your temps post turbo but pre intercooler would not be hot at all
hey guys brenny heaaar
But radiators are only meant to reduce heat via convection. That is why engines in moving cars with airflow are cooler than engines in sitting traffic. That is also why there are fans on radiators. The black radiator actually performed worst in the fan scenario, which is the scenario that all cars actively employ.
Which means: If you have a radiator to just sit there, paint it black; If you have a radiator in a windy environment (like a car), keep it silver.
Great response!
Engineering Explained, a very nice and educational car channel, shows why this is total BS.
He tore the theory apart so gracefully xD
Paint is an insulator. The results you see are purely down to the paint drying (drawing out heat) . Do the same test after a few weeks when paint is fully cured and you will see why this is a bad idea.
Hmm. Good point.
Absolutely the wrong conclusion. They were so focused on the huge change with no airflow that they ignored the FACT that the bare aluminum one performed better by 3% with airflow. When do you need your intercooler to perform better - when you're at a stoplight and the turbo isn't providing any boost, or when you're moving and the turbo is boosting and adding heat? If you care at all about its efficiency without airflow you understand nothing about boosted engines. 3% better heat absorption can mean the difference between detonation or not.
The black paint does, however, effectively reduce the temperatures gained through heat soak at a standstill, which can be a problem for many cars
Would the 3c difference from the cooling fan perhaps be due to the extra layer over the intercooler from the paint? Great ep!
Or maybe the battery they used had drained just a little bit, 3° over 100° is fairly insignificant anyway.
3 degrees is insignificant
Keven Harvey
Exactly what I was thinking
yup. exactly. read my comment for more details :P
You also have to consider the test environment. They have a room space that is not at a constant temp. If it's an open garage for example, you may also have a slight breeze that will influence the result.
Typically with data analysis you are looking at large trends and significant differences. Now to know what's significant, you need to run several tests and understand the sense of scale.
he literally says "the amount of heat lost to radiation is probably insignificant compared to the amount of heat that's lost to convection with the air flowing through it." @10:54 His point being when you're sitting still, there's no airflow, so no convection just radiation, so the black paint DOES make a difference. EXCEPT that your intercooler probably has a fan on it, to make sure there IS air flow, because it IS reliant on convection, radiation is in his own words "probably insignificant."
Yes, the paint made the the intercooler a better radiator and a worse convector, great if the application involves mostly radiation, but in the real world of moving air it performed worse overall because of the insulation.
The amount of heat gained from radiation is a significant factor as well. In a garage the intercooler is not receiving much heat. Close to a hot. engine and blazing hot turbo charger and emissivity is working against you. Emissivity is a 2 way street. Good at sending means good at receiving. This is a great show, but here they were not correct. If you really want a black intercooler, get one anodized.
how the fuck are you going to be building boost/heat while stopped in traffic... the entire point of it is to work while moving, not stationary.
Engineering Explained - Mythbusting Mighty Car Mods. An Engineer who understands science talking about why they are wrong.
MCM - Two guys who have mechanic friends talk about what they think.
Yeah I'll go with the engineer, as an engineer myself.
White blocks heat transfer and black increases heat transfer = Undisputable law. But a coating of paint reduces the heat transfer. However anodizing becomes a component of the aluminum and stabilizes and makes aluminum more durable. And black anodizing is available.
great show, cheers fellas!
hey paul
PAUL TOKIN
honestly paul i would of never thought you would watch these people. thats fucking great
fuckin paul tokin! yo!
whats good paul!?
This mod was used on my Ford Escort RS turbo in the late 80's AND YES IT WORKS TURBO systems motorsport who were one of the UK's top ford tuners in the day and Colins performance both recomended this mod and its cheap easy to do and works.! Also adding a deflector plate helps to by diverting more cold air to it! "Forget the doubters this is real" ( If there are any april fools here its the people who didnt paint theirs! lmao.) !
This video is 7 years old and is still entertaining.
An intercooler works through convection not radiation. they seem to be ignoring the results from having air passing through the intercooler. However that's what they should really be concentrating on as the vehicle that the intercooler is fitted to is designed to be moving.
Love your channel. And I applaud this scientific testing. But I think you have flawed results. The painted intercooler is covered in fresh paint. And that paint is still evaporating it's solvents. So it is not just giving off heat by radiation. It is also evaporating, (just like if you had used a water spray) and of course there is some airflow due to convection. Given enough time to cure, a week, a month... the advantage of the fresh paint will disappear. And the 3% gap seen with airflow will likely widen due to the insulation effect of the paint.
A better test would be 2 identical intercoolers from the same factory, one bright shiny chrome on the outside, one anodized black.
+Brad Rex You worded it better than me.
It's only logical that a painted cooler will work less well than a raw one.
9:16 Plain aluminum intercoolers emit colder air than black intercoolers WHEN THE CAR IS MOVING. Since we want cars to move, and colder air is better, your conclusion is most puzzling.
If painting the intercooler black did anything, I would think that it would make less power since black colors absorb heat as opposed to reflecting it? So black would only really be wanted if you're going for more of a stealth look instead of a nice shiny intercooler. :)
This is exactly what that just tested.
+jeepmanxj I know that, I was just stating my hypothesis. At the end of the video they stated that black was actually better which surprised me.
Black absorbs solar heat more than any other color, but the intercooler isn't going to be mounted in direct sunlight so its solar radiation heatsoak vs. the larger cooling area benefit is going to be negligible. Lol
Proved you wrong son! :D
actually that black gets hotter is not true, only a myth that has been busted, on the other hand the paint in itself obserbe heat better then the bere metal so there is maybe a minor difference but not so big difference that the engine would notice.
Nice!
I love ur vids
hey! :D
Years ago my friends and I did a simular test with two identical IC's but we powder coated one instead of paint. The powder coat was a plain powder no ceramics and was black in color. From what we found the powder coated IC had a hotter discharge temp being almost 40 degrees hotter then the non powder coated IC. There's obviously a big difference between spray paint and powder coatings and the PC seemed to actually prevent the dissipation of heat throught the IC. Not sure if ceramic PC would have the same effect or not. Good to know that regular black spray paint actually helps. After our tests we kinda assumed paint would have the same effect as PC but just not as much.
I actually work at s powder coating shop ... This is something I must ask my boss on whether ceramic coating or powder coating work better to cool down metals ..
I actually work at s powder coating shop ... This is something I must ask my boss on whether ceramic coating or powder coating work better to cool down metals ..
Emissivity is a 2 way street. The ability to emit heat via radiation is always equal to the ability to absorb heat. A radiator or intercooler in an engine bay emitting heat via radiation can just as easily receive heat from the engine, turbo, or other radiators. The heat it radiates may be reflected back by metal body panels and structural components, or may simply heat those up.
In the test in the video, the intercooler is not close to a hot engine, radiator AC radiator, or oil cooler.
In the test in this video the black intercooler is 3% less efficient than the silver with airflow, even with all those hot components around it.
We are all free to paint the radiators and intercoolers of our cars black. Heck, pull your refrigerator away from the wall, and spray it's radiator black, then hit the out door AC unit of your home. But you'll find efficiency drops, rather than improves.
since when radiator of a refrigerator is something other than black? they work with both natural convection and radiation. Your understanding is unrelevant. And your example. You can see efficiency gains because convection is better than radiation in MOST cases. Even a smallest wind can make you dumb.
@@sametbayboru8965 Most refrigerator radiator are unpainted silver/grey. The little college ones with an exposed radiator in the back are painted black because they will be handled and oils from fingers are bad for the finish. So are most air conditioners, car radiators, intercoolers, oil coolers, etc etc. Silver/grey. I'd post some photos, but extreme losers will then tag the photos as spam and the post disappears. Loosers....
Anodizing an IC any color will make it perform better than the stock bare aluminum. This is because the anodizing has a slightly rough surface which provides more surface area to dissipate heat. However, painting an IC black will insulate the IC because it makes it smoother which will decrease its efficiency when air is moving over it. When they had air flowing through them, the shiny had a 100deg difference where the black had 97deg. That right there is the paint insulating the IC and where anodizing would out perform.
In terms of when there is no air flowing through, anodized and painted should have a similar efficiency based on emmisive properties when painted black, however, the anodizing will still have the extra surface area to dissipate heat along with the emissive properties (taking the lead over paint).
Basically what im trying to say here, is spend the money to get it anodized (maybe 100$) and have the double benefit of more surface area and the black emmisive properties so you gain when in stale air and when moving. If you cant anodize it, it had better be painted black because all other lighter colors don't have the same emissive properties.
Id like to see MCM anodize an IC black and see what results they get
You should dino a car with a silver intercooler and then change it for the same black painted one. Just so we can see if there is a HP difference and a valid reason to spray it black.
You could learn to spell dyno....
SpazN16 Oops! Sorry :P Typo xD
With most things related to a car, this may not actually turn out to be a tangible effect, however it should prolong the life of your turbo with better cooling and theoretically, a colder turbo should mean it spools faster, but there are some many other variables in a car that it probably won't show us much of a difference.
Ian Meiksins I see what you mean. Would be good to have it mythbusted though :D
That theory doesn't make sense... The IC is after the turbo, so painting the IC black will have no effect upon the turbo... It will push the same amount of air with a painted or un-painted intercooler....
If you live in LA a black intercooler is ideal. try sitting on the 405 at 5:30pm.
get a motorcycle and lane split it will cut your commute by like 2 hours haha legal only in CA!
Cant beat the comfort of a car!
Yea because you are totally boosting wile sitting in a traffic jam..... Black radiator would help much more.
Jeez my wrx reached 190f in LA traffic. I got off and drove on the street instead.
Zcypot
Thats not really that hot. For my Chevy, 210f is right in the middle of the gauge.
Loving the mythbusting episodes, really getting down the the science and shizuoka behind parts and stuff. Keep it up guys, fantastic.
97 deg C reduction (with black paint) is WORSE than 100 deg reduction (with bare aluminum).
Furthermore, under what scenario will the engine/ECU go into boost (and require cooler intake air temp) while there is no airflow across the Charge Air Cooler fins?
Finally, a CAC sheds intake air heat via convection, not radiation. Black paint would affect radiant heat transfer, not convective.
Save your spray can for something else.
P.S. Props for using sensors and collecting data (into Matlab as well). It's just that the conclusions drawn are not very sound.
"a CAC sheds intake air heat via convection, not radiation"
Yeah.... No.
It sheds heath through radiation/advection to the air flowing outside the ducts / the water then the fins, then the ducts.
Please don't forget that there is a wall of material that is not subject to convection _because it is solid_ .
Okay, but I wasn't going to write a whole textbook on heat transfer in a yt comment.
Actually, it sheds heat via conduction and radiation. Heat conduction, also called diffusion, is the direct microscopic exchange of kinetic energy of particles through the boundary between two systems.
When there is no airflow through the radiator by advection, the air particles "trapped" in the heat exchanger fins heat up so those particle temperatures move towards equilibrium with the particle temperatures in the skin of the heat exchanger, which is moving towards equilibrium with the temperatures of the air particles inside the heat exchanger.
These "trapped" particles don't stay trapped. Convection causes the less dense air particles to rise out of the fin gaps, being replaced by cooler, denser air particles.
Advection, or pushing of air horizontally through the heat exchanger fins, allows the air heating up through conduction and radiation to be replaced more quickly by cool air, allowing for a larger temperature differential between the particles in the heat exchanger skin/fins and the outside air, allowing for a higher conduction rate.
One thing to remember is that radiation works both ways. Every fin is emitting radiation towards its neighbour, and every fin is receiving radiation from its neighbour. Some of that radiation is being absorbed by the air. Increasing the emissivity by painting the heat exchanger black allows more energy to be emitted as radiation, increasing the amount the air particles are warmed, but decreases the amount of conduction as a result of the paint acting as an insulator.
Also, the engine is a massive radiation source. If the engine is a 150°C heat source (as an arbitrary figure) and the heat exchanger is a 100°C heat source, net effect will be heat exchanger receiving more radiated energy from the engine than it radiates towards the engine. A low-emissivity heat exchanger will be a bonus in this case, as it reduces the 'heat soak' from the motor.
It would appear from this experiment that conduction occurs at a higher rate than radiation with an unpainted heat exchanger, with the two forms of heat energy transfer much more closely matched when the heat exchanger is painted black. Given that advection will occur when the vehicle is moving, therefore generating boost, therefore requiring charge cooling, I would go with not painting, or applying a coating with high levels of emissivity AND conductivity. Black anodising sounds like the business.
black is worse. First graphic proved it in their own video. with air flowing silver gave 100 C difference black one 97 C difference. That 3% better as silver. Intercoolers are designed to use convection not radiation. Black will also pick up radiated heat from other parts of the engine compartment too not just sun light.
If you're considering the *Difference* between the air temperatures in and out of the intercoolers, then doesn't that means that the higher it is, the better?
Therefore without airflow, the black wins (due to emissivity) but with airflow the non-painted one wins, due to convection. and since the vehicle will typically be in motion, painting it black will be disadvantageous
just sayn...
The one with paint won because of wet paint. Not because of emissivity. Evaportation is great and is why many systems sprits the intercooler with water.
I always thought people did that to make it "stealthy"
Because a lot of people can see a big shiny intercooler from far away.
Intercoolers works by convection, not radiation. You are having a 3% efficiency loss by painting it black. Period.
Correct. Painting Black is bad news. Especially if it’s exposed to the sun
@@BespokePowerhouse The sun is 93 Million miles away, how about the flaming hot turbo, or the engine block? You want your intercoolers and radiators shiny and reflective. Bounce that heat away.
Marty and Moog, your conclusion should have been: Don't paint your intercooler, or radiator for that matter, but add a small electric fan to it for when you are in traffic or at the drags. much simpler than painting it. The paint made the intercooler 3% worse with air moving over it. cheers fellas
They have an episode where they make a system to squirt cold water onto the intercooler.
This mythbusting has been mythbusted!
EngiEx has officially killed this video :)
i think if you consider that behind the intercooler would be a hot engine, then the black maybe will absorb that heat and will make it less efficient, also the paint is an extra layer of insulation, by its own and stationary it is better but in the car i am not so sure. My thought is to have the front side black (maybe not so good if direct sunlight hits it but does the job) and the side close to the engine heat a reflective silver
or you can make the zebra-cooler. Both worlds combined, it is the unicorns mate
black doesn't absorb heat, it only absorbs LIGHT heat.
Huh? Why don't you speak with proper terminology? Convection and radiation. Black does indeed absorb radiative heat, which a hot engine would definitely be emitting, depending on its outer coating. It should either be polished to a mirror surface or coated with another metal to behave as such.
im pretty sure black absorbs light energy and not actual heat itself...
Yeah, a hybrid radiator. =)
Black painting of intercooler/ radiators etc is done purely for looks. It will in fact reduce the efficiency of intercooler/ heat exchanger. As it did by 3% in your case.
Love your videos btw.
I wonder what kind of difference would be made if, instead of using paint, the intercooler was anodised and dyed black during this process. In theory, by having the black _in_ the aluminium instead of as a coating _on_ the aluminium, you should be able to achieve the higher temperature differential of the black unit without any insulating effect.
Marty's opinion aside, painting it black at least makes it look cooler even if it doesn't actually make it cooler.
I guess the paint didnt fully dry (if you wait a couple days or maybe weeks) . Because of that some of the paint would evaporate and take a little bit of heat with it. Im not sure tho...
What happens when the intercooler is sitting next to something hot though - like a radiator or AC rad for instance? Would love to see what happens on a dyno.
Exactly, we need to test for this as I assume the black intercooler would absorb more ambient heat
A dyno can't simulate the actual situation that there would be an actual benefit of the black paint as the car is mostly indoors and with a huge fan blowing air regardless of the car speed. Moreover running cooler wouldn't produce more HP. You would need a new tune to benefit from the engine's improved tolerance.
do some rearranging
n00b1n4t0r The fan on a dyno can be turned off to simulate sitting in traffic so it would be a decent test. Also every turbo car I have heard of in the last 15+ years has knock sensors. They adjust timing according to when detonation starts (well it goes off a count of how many det's occur). Basically if the intercooler keeps things cooler the ecu can feed in more fuel and advance the timing more. It will definitely make more power.
It might be 8 years later but it seems you guys were correct in your conclusions. What has been falsely banded about here and via Engineering Explained is that intercoolers and on the same principals, radiators, work via convection only. This assumption is flawed and incomplete. They lose heat via both modes. However as air flow is introduced the convection component of the total heat loss of the system increases for both the painted and unpainted coolers in relation to their radiant heat loss component and so the insulating effect of the paint marginally decreases the system efficiency (97%). At the same time the converse is also true in that with zero flow (static) air the radiant component of the total heat loss increases by which you demonstrated the black painted one had a significant improvement over the shiny bare Al one. If intercoolers and radiators worked via convection only, every working ICE powered vehicle on earth would have massive over heating issues. That radiant element of total heat loss can be felt by simply putting your hand near a rad or intercooler while the vehicle is at rest. Exalting thermodynamic principals to a religious level like holy scripture is folly even more so when rudamentary flaws in basic assumptions are made by those who Explain Engineering and claim to 'know better'. At the very least an apology is due to you guys from you know who :)
the reason why you paint the radiator black is to even out the heat distribution. if they ever do this agian. i think a Infrared camra would be great addition to the test instead of just sensors.
I clicked this video thinking it was BS after watching it you guys changed my mind. I think I am going to paint my radiator and oil cooler black . Great vid guys.
I was wondering if this can also work with radiator condenser evaporator to improve cold in my a/c
of course it does -,-
I just spray painted my computer's heatsink and CPU itself (used that as thermal paste, just apply the heatsink while the CPU is wet) and nothing is working.
HALP!
***** No, but apparently you are for not understanding basic sarcasm via a story filled with obvious bullshit.
Fridge condenser radiator is black to help disipate heat. Transformers are painted often in black, to help disipate heat ... Nos CPU coolers man, that is not fashion ... let this weird look for HP
38911bytefree I once had an HP laptop that used a painted black heatsink. Unfortunately the thermal paste system is shit. They put tinfoil on the heatsink then put thermal paste there then put it on the heatsink! All the crap dried out and I had to totally scratch it up. Right now the fucking memory sockets/controller don't work properly it made the fucking laptop USELESS!
9:01 from 100°C to 97°C temperature difference is not a negligible improvement, it is a small worsening. And with higher windspeeds, which are likely to occur in real circumstances, the worsening will be even greater. So your conclusion of does no harm is plain wrong.
Did you just say "small worsening"? ... and then the "worsening" would be even greater? How about small disadvantage? I would like to point out they said the disadvantages are outweighed by the benefits when sitting still. Also, you're missing the point. They clearly say that there would be an advantage IN traffic and AT the drag strip. Basically painting it black would help prevent the intercooler from becoming overly heat soaked so when you hit the gas once traffic clears or the Christmas tree turns green you could get some cooler air than if it wasn't painted. Furthermore. 3* isn't really a huge deal when it comes to intake temperature however, when you're sitting at a stop a difference of over 40* is a HUGE difference.
+Dan W First, it will be more than 3° because normally you drive faster than this fan blows. Second, when standing still, your turbo isn't really working that much so you won't "heatsoak" your intercooler anyways.
I have some questions. First what about other colors. Does the color matter? Second, how long after you painted, did you do the test? You might have had volatiles left in the paint which throw off the test. Evaporating paint emissions could also effect heat transfer.
1. Read about isolation (in this example it is the black paint)
2. Read about thermal conduction.
3. Even in this video 9:13 "with airflow" (which is the more significant for actually DRIVING a car) you have a bigger delta between in- and output on the non-painted intercooler.
4. You would lose (not noticeable) HP when you paint it black but never gain power..
5. Black paint would only be an asset on an intercooler if you want to keep your car unobtrusively.
+1 on the anodizing. That is what i used on my Diesel intercooler. Dropped my intake temps by almost 60 deg in real world use. I just did it to look more discrete, And black looks sick!
Whats under the cover at 11:43 ? Show Car? Drift Turd? I cant really see flared wheel arches though...Hmm
Could be the Mira half-cut that Moog got him in Kei To The City.
drift car is long gone.
No its not...did you watch the Behind the Scenes of Kei to the City?
I think he was talking about the 180, not the Mira
oh yeah...
So when you're not moving (no air flow) you can go faster?
Heat soaked... Custom software... I fucking love this channel.
*****
it appears he's got an arduino monitoring all this, so it actually would take some custom software to interface it with matlab.
*****
Matlab is an evil thing conjured by only the darkest of souls.
5:05 he says "painting it black changes emissivity and that has nothing to do with airflow".. but an intercooler literally works by cooling flowing air :/
He is talking about the air flowing across the intercooler not the air flowing through it. He is saying that air flowing across the intercooler or not flowing across it has nothing to do with difference of the amount of radiation that can be released because of the color change.
Yeah and the result was that it was 3 degrees less efficient but they completely ignored that. The point is the emissivity doesn't matter because the intercooler's job is to cool the air that's flowing through it. They did the test and the black one was clearly less efficient.
@@chubzdon1 emissivity does matter. If your intercooler is near a hot engine or worse a turbo, you want it bright, shiny and reflecting away radiant heat.
IF YOU ARE COOLING A HAIRDRYER IN A GARGE, BLACK IS GOOD!
Watching this before Engineering Explained video.
Black paint sales just went up 30% over night xD
Plus: if you have a *_BLAAAAACK_* intercooler (plus *_BLAAAAACK_* piping) means that you get a lot less attention from Australia's fine authorities.
So they conclude that the black is better dispite the alloy one actually cooling the air better when doing the test it was designed to do? Or have I got that wrong
+stephen reed You are spot on. They think because black wins standing still, it's best. But a car does not stand still! IN those circumstances, black loses. They proved it, but still Electronical Stig made the wrong conclusion. Funny!
+stephen reed Could you guys elaborate?
It loses because intercoolers work through direct conduction to the cool air blowing past the exterior surface, not the piddly amount of radiative cooling you might get with a different color paint. Paint acts as an insulator and reduces the efficiency of the bare aluminum metal's excellent thermal conduction. Even if the car is sitting still, that tiny amount of extra radiative cooling will not benefit you once a significant mass of hot compressed air starts flowing through that intercooler, and the insulating paint will only slow down that heat from getting to the outside surface of the fins to be conducted away by ambient air.
makes sense. most radiators i have dealt with on my cars as well as friends cars have all had the black paint layer on them.. jeeps etc. i always thought it was a protective coating more for preventing the oxidation of the aluminum and from damage from road debris like sand as well as aesthetics on the front end of such exposed openings.
so for it to improve it capacity to radiate heat away brings the whole thing full circle. and radiant heat is radiant heat so doesn't matter if it hot air or hot water flowing through, the black coating would help. but i will say it probably does matter what type of black paint is used as some paints would insulate more than others. like the coatings used on exhausts that contain ceramics to actually trap heat the same as fiberglass exhaust wraps do.
The surface treatment of the IC prior to coating, the composition of the coating, the applied thickness all play a role on whether the coating will act as a thermal insulator or conductor.
Aren't black aluminum intercoolers Anodized?
I always wondered why turbo guys leave it unpainted. This was figured out years ago with early VW mods. The polished or chromed tins around the covered oil cooler and head tins would increase engine and oil temps. Painted one's, disapated heat much faster and brought down temps considerably. They found this out to be true with radiators as well.
Thanks for your experiment though.
Will adding a blue viper logo (painted on) onto my black big mount intercooler for my srt4 do much to it? It’s already black
FMIC logos add at least an extra 10 wheel HP from my experience
anew742 nice! No I was just wondering if it would change much from being painted multiple colors
@@connerhendrickson8418 Please be trolling, please be trolling, please be trolling...
Great experiment guys. Its pretty well controlled. Food for thought: There was likely a percentage of the paint solvent which remained until your static heating by the hair dryer. Paints typically take 24 hours to have 100% of the solvent to evaporate. The evaporating solvent has a latent heat of vaporization which pulls energy out the surface from which it evaporates. (dropping the temperature artificially low) I wager that a re-test of the same black intercooler will yield the same result for the airflow test while yeilding a smaller deltaT for the first test. Emissivity does matter, but radiation is orders of magnitude slower than convection or conduction. I am going to be a Dr. in this field, hence the science in my vids. :) Keep up the good work guys!
Its not the color at all but the top layer emissivity that effects the heat loss by radiation.
If you look into it, different materials have different emissivity levels. This means that alumininium or chrome for instance has a very low emissivity value. Paint the aluminium though and NOT because of the color change but because of the top layer emissivity, heat radiation changes.
Try it out: heat a chrome bar and hold your hand near it to try and feel the radiation.
Now apply tape or something more heat resistent (paint...) all over the surface and redo. There will be a noticeable difference in radiation because the top layer emissivity changed.
As a thermographer, I know.
What were the ambient temperatures during each phase of the test?
Your conclusion is backwards, 100° temperature difference in inlet and outlet temperature with the bare aluminum intercooler, and 97° temperature difference in inlet and outlet temperature with the painted intercooler means that the air coming out of the painted intercooler is warmer than the air coming out of the bare aluminum intercooler. If the outlet temperature of the painted intercooler was 103° difference then it would mean that the painted intercooler was more efficient. Your test proves that a painted intercooler is less efficient than a bare aluminum intercooler, with airflow through the intercooler, which is how it is designed to work.
James Mosley you are correct. Plus, the without airflow test is irrelevant because in All situations you will be having airflow. On a dyno, street racing, race track. So the non airflow test doesn’t matter one bit EVEN IF it wasn’t backwards lol they had some good ideas but poorly executed.
for this crude test a
@@badass1g I didn't know days where the air was still counted as airflow. No seriously, you will not have airflow ALL the time. You will have idle times, it's inevitable. Besides, the efficiency on the high end only dropped by 3C which is pretty insignificant, meanwhile you have that massive gain on the low end. Overall painting it comes out on top.
@@anonjohnnyG 3% difference is not standard error, that is statistically significant
@@Lawtonfl re read my comment and try again
What you're seeing is three dudes who don't know the difference between radiative and convective heat loss. The intercooler is a radiator, so relies entirely on airflow through it to cool it. Painting it black just creates a slightly less conductive coating on the surface which makes it less efficient.
+Cardinal Biggles: "What you're seeing is three dudes who don't know the difference between radiative and convective heat loss. The intercooler is a radiator ..."
Lol, apparently you don't either, the intercooler is *not* a radiator. (Although it is also wrongly called that in common language like your water cooling radiator which is also a convector, not a radiator)
Technically speaking it is a radiator - without airflow it will still radiate heat - it's just not a very effective one.
Scientifically speaking it is also a radiator, just like every other part of a car, but calling it a radiator because of that is just meaningless. Do you call the mirrors radiators as well?
Technically speaking - that is, in its designed mode of operation - the intercooler sheds 95% to 100% of the heat through convection, ergo, it should be called a convector.
the one thing that might have messed up the results is the fan is blowing at the intercooler right, and the tubing is open facing the fan. car fans do a really good job blowing air over a wide radius. my worry is, the reason why with air flow both cars were nearly the same is because there was air flow going into the tube and interfering with the outlet temp. with that said, i like the silver intercooler look, i mean comeonn. black may be awesome, but shiny silver is also pretty sweet.
Marty dropping the fan just made my day.
Can't deny the science here. Your own experiment proves that black paint on an inter cooler is less efficient that with plain aluminum during air movement. Ever notice that the transmission cooler located at the bottom of the radiator is painted black? And that the top of the radiator is painted black? Probably to prevent rust during rain/water splash. But think about this. An aftermarket transmission cooler placed in front of the radiator cools far better than in the stock radiator. Why? Airflow.
Only slight less so. And by using much less energy by going completely fanless, just painting it black results in much better performance. I'd say that's a clear win by far for performance-to-weight ratio.
Jason Alexander well the fact that you're cars rad is already trying to keep your engine coolant cold is a big factor also.
Air flow is a big part, but equally significant is the fact that the fluid cooling through a dedicated cooler is not impeded by the temp of the coolant circulating through the radiator core! The fluid temp can only drop as low as the radiators overall temp.
That dude needs to get like 20 hrs of sleep asap!! His eyes were purple as fuck!! Lol
Engineers don't sleep.
Hahahahaha i was thinking the same thing
from how different the colour is i think he should get a blood test for liver health.
Maybe he's just high as fuck.
88djdmepfdnkjf94 Werent you listening ? Darker is better, faster, more efficient !
Very entertaining! I love a garage test lab as much as the next man. But seriously? The only thing that would convince me would be a dyno run before and after paint. So once I've fitted the intercooler to my bike, I'm leaving it yellow...
This is one of the best videos yet!
The temperature sensors monitoring heat in this video is mounted externally. paint acting an as insulator will have less heat outside. the proper way to do this test would have been to have the temperature sensors inside, where the airflow is traveling.
I'm thinking the conclusion should be to add a fan to the intercooler that comes on when the airflow drops below a threshold.
You guys should read up on ‘confirmation bias’. You so wanted it to work you called the test with airflow (you know the one like how a car operates) showed a negligible improvement, NO, it made it worse, sorry guys, great idea, good test, screwed up the conclusion.
so this would only be beneficial if your intercooler was mounted behind the bumper out of suns reach? I live in PHX, AZ so there's always sun out.
I had just come across this video, so I apologize for being late to comment. What if you were to black anodize the aluminum on the intake. Would this not be a thin enough layer to still keep most of the emissivity of the aluminum yet combined with the effects of being black? Not an engineer but I am curious. Thanks.
+Robert Elmore I found data for black anodizing that said it was 200x less conductive to heat than base Al but emissivity was 20X greater. Under some conditions anodizing will transfer additional heat by radiation, but only if the surrounding surfaces are kept at a lower temperature, and you have enough cooling airflow to counter the reduction in convection due to the lower conductivity. Need to test...!
but wouldn't black intercoolers be anodized? in which case the coating would not affect the aluminum temperature characteristics?
@Nybbl er Anodizing is not a coating, it's created by oxidizing the surface of aluminium. which can be dyed to any colour. Anodizing actually significantly improves the performance of electronic heat sinks by significantly increasing the surface emissivity from around .05 for bare aluminium to 0.85 The colour makes no measurable difference
Anodizing would be better than painting. But if the intercooler is in a car near a hot engine, tube and radiator, you want low emissivity, silver.
For cooling hair dryers in a garage, paint works great.
DERP, with the fan (convection) it cooled worse...
These aren't designed for emissive cooling via radiation...
Why do you always take so long to upload videos :'( one a week minimum please, I would even pay monthly for it on tv if I could! best thing ever! should be on tv. love you guys!
Will this work with Radiators as well? Reason I ask is that I've a Polo 6R 1.2TSI which has a charge air cooler that is cooled by radiator liquid passed thru a secondary radiator. I've been busting my head on how to get the IATs to drop but short of a larger radiator, I've run out of any solution which can work, UNTIL i saw this video.. please please help here :-)..
I would go for it!
....but I would remove that radiator from the car and clean it thoroughly
Part of the small difference between bare and black (with air flow) might be the layers of paint impeding air flow by reducing the distance between the cooling fins. I would think that if the inter-cooler was black anodized, instead of being painted, the difference would be greater. Also, the interior of the inter-cooler still being bare, when just being painted, is a factor too. An inter-cooler of black anodized aluminum (black inside & out) might show completely different results for the better. JMO.
I'm surprised that you guys didn't do a dyno test too. That's what really might show whether it's worth it. Also, JMO.
This just in, MCM can you please test the following performance difference, a car with and without wheels.
Whilst the car isn't driving, say at traffic lights or in my garage, the one without wheels will have a lower weight, and therefore will race faster. Right?
+James Hillyer
Marty : "I have a cable tie" ROFL :))))
best thing to test would be take a stock intercooler.. install it on a car and put in on a dyno than spray it black and put it on the dyno again..
Important: remember that behind the intercooler will stand the radiator, which is hot. So, for better performance, the back of the intercooler should be reflective (low e), while the front should be emmissive (high e). Hence, if you're thinking abot painting yours black, do it just in the frontal area. The test these guys performed is enough to prove a point, but you gotta keep real instalation conditions in mind! Cheers
So pretty much painting the intercooler black disperses more heat through radiation, but making almost no difference under convection due to the insulating layer of paint.. so does this mean if you can somehow change the color to black without applying an extra insulating layer to the existing aluminum, then you can finally reap the benifits of it?
If so then can there be a substance mixed into the aluminum at creation to change the color to black without needing an outer insulating layer? Interesting.. 40° is alot. Its the difference between driving in the summer compared to winter for turboed cars..
Maybe time to revisit this??? More science? Maybe cheap ebay vs expensive?
my only question is how can you come to the conclusion that radiation is more prevalent than convection when convection produced better cooling results in both cases?
Radiation doesn't depend on fluid movement for cooling.
Essentially, radiation uses the characteristics of light (EM properties), whereas convection uses the fluid interacting with the heat source (air moving past the radiator).
right, and a car radiator (despite its epic misnomer) doesn't dissipate the majority of its energy through Radiation and so trying to focus your efforts on improving its radiation while hindering its convection is really dumb.
oh I agree, but it would explain the results.
thermostats in cooling systems regulate temperature but just as importantly the flow rate of coolant through the radiator as it needs to be slowed down to allow the heat transfer to take place.if the coolant flows too fast (ie. if you thought removing the thermostat would help your overheating issue)
the coolant passes through the radiator too fast and back into the heat of the engine thus not cooling your medium efficiently and ending up with over heating.
basically you cant keep your charge air in an intercooler long enough for this whole idea to be effective so as it goes the r and d of the big car performance brands is probably why what we have is about as good as were capable of at the current time!
That guy needs some sleep
After cleaning dye from a flashlight where aluminum plate with soldered led touches anodized aluminum I got flashlight getting much warmer than before. I used pipe cleaner with powerful alkali. After pure aluminum was exposed added thermal paste and got a good thermal spread. Even anodized aluminum in my flashlight was bad for thermal resistance.
I have just done this and it's helped no end and it's on a diesel very highly recommend!!!!!!
Really? Looking for performance differences between two colors? Now I'm a fan of MCM, watched turbos and temples like 20 times, watched every episode, so don't take me as a hater when I say this is just low quality for the channel. Ok, I got it, you are building an awesome project car, but make us wait for so long to have a tutorial on how to apply stickers and this, is just low for the MCM I love. Hope next videos are more entertaining. ..
They just got back from america plus they have real job's and this stuff doesn't pay for it self.
A real MCM fan would be patient and enjoy what was released to be a 'tie over' episode. They only put it out so that they weren't inactive for too long. They have lives outside of MCM. Try to be less selfish and be happy that they are currently tackling a project bigger than they ever have for YOU and the other (perhaps truer?) MCM fans.
The LoudAssasin
Dude, MCM gets LOTS of money just from youtube revenue...!
I like their Mythbusters-esque episodes.
what if you anodized an intercooler black.... it wouldn't insulate at all but would still have the benifits of the blackness and might be more effective
I was thinking this, and I think this may be correct, however the actual importance of radiation compared to the convection and conduction of heat in the intercooler would make that an expensive and very insignificant upgrade.
It's Barney but..... for science?? but seriously I do agree I just want to see it done. the situation I think it would be really good in is stop and go traffic and keep in mind a manufacturer could easily overcome the cost by building a lot of them. so yea I agree it would be dumb for an individual to do but maybe we could convince a good manufacturer to do it if there was evidence (easy advertising) already done to support it
Yeah that would be cool. Maybe also other colours as well! A red intercooler could look mad!
To this day, the tech geek still hasn’t slept.
He's on the shabz
if you able to keep the black paint cool like keeps your car moving then the coat shouldn't matter. the extra coat will keep certain temperature along the way as you moving. its like putung a left over food in a metal container. as long the container remain the same temperature the food will stay warm.
Heat is not just from visible light. Your engine is emitting tons of non visible wavelengths (infrared) and the black inter-cooler will absorb that much ore than a silver one. Additionally, your environment is much cooler than an engine bay, so the percentage difference would be a lot less if the black did work. Your "scientific test is not well-designed an it doesn't take this these factors into account. Try doing it in an oven that approximates engine temperatures.
I painted my intercooler black because I don't want people to see it. Any performance gained or lost from painting it is negligible.
You must have mixed up something there with the calculation of the deltas...
how a difference of 97 degrees (black) is better than a difference of 100 degrees(no painted)??
When you are stopped at a stop light the intercooler doesn’t have hot air blowing through it because the turbo isn’t spinning and the exhaust is cooler. It isn’t realistic to think that it will have extremely hot air going through it at a standstill.
I'd bet that they didn't wait for the paint to properly cure and during the first heat test without airflow the paint cured and offgassed, causing it to shed heat faster. This also points to why it made a negligible difference under airflow since the paint had cured.
Why not test them properly and put them on a car and a dyno? Gotta be more trusty than a hairdryer.
hi baby
fleetwoodsucks Stalker.