Everything was the same so the power is the same. The reason I like the w2a is the extra ceiling. Our own car dropped from 56C @30lb in the traps with A2A to 20C with the W2a. Power was the same at first.. but with those low temps I was able to add more boost. A lot more boost. Maybe you should have added boost and timing till both intercoolers had the same outlet temp and then look at the hp difference.
Totally agree; was about to post the same. If the ATA setup was octane/ knock limited or tuned to the point that it was knock limited, you’d see the difference between the ATA and ATW intercooler. 14 degrees won’t be a huge difference, though. Would’ve liked to see the ATW run with ice water to show POTENTIAL difference, too.
I was just telling Dustin Lee that Paul Harrell is like talking engines with guys that know what they’re talking about. Literally 10 minutes before I watched this.
Thank you for posting videos on everything, everyone thinks about! Anytime I've got a question, I pull down the search menu for your channel, and whoop there it is ! Thanks Richard!
The air-water inter-cooler has a greater mass to transfer the heat from the intake charge. That's why its less susceptible to increased temperatures and the resultant heat soak.
Being that the test were run at WOT, I'm assuming the engine management system was deep into power enrichment for both runs which could have negated the higher IATs of the air-to-air intercooler, which one could argue that the air-to-water didn't need and robbing it of power. Also, given that both had the same ignition timing, it would have been safer to advance the timing on the air-to-water setup which had the cooler IATs before running into knock. There was more power left on the table, so to speak, that wasn't taken advantage of through tuning.
I ran one of the first V2SQ supercharger kits on my 98S10SS. It didn't come intercooled and it didn't like anything over 8-9lbs and would see temps go north of 200F. I eventually added meth injection and it loved it. Went to 15lbs and with a 50/50 mix intake temps would stay around low 70s. With windshield wiper fluid around high 90s low 100s. Definitely worth it.
Absolutely love the videos keep up the great work! Would like to see a difference between the two on a max effort higher horsepower application and maybe throw ice water in the mix maybe at a 1000 horsepower 😀
I think a temperature probe on the outlet of the turbo and on the outlet of the intercooler would be nice to see. It would be interesting to see a graph of those two values and the intake air temp all plotted on one graph during a run. Another idea for a dyno test would be an air to air intercooler shroud design. Corky Bell talks about necking down the ducting to the intercooler in his book.
Why’s the power the same? Because the IAT wasn’t different enough to have to change ignition timing to resist detonation and the difference in air density due to it was trivial.
Basically the Boost curve would be identical. The difference is about 3% less hp around the curve entirely under boost with no intercooler do to the inefficiency as the heat in the inlet would be +165'F
Thank you very much for this, Richard! This kind of information is extremely interesting and useful to guys who are building cars for dumbassery like I always am. :)
Is it possile that the air to air intercooler was slightly less restrictive than the water to air cooler thus compensating for the slight increace in charge temprature
No, you can’t match air speed across the core for the air to air. The air to water is using a pump with water pressure to force cool water across the core.
Exactly. So even if they were at the same boost at the intake, what was the pressure and temp before and after the intercooler? How about the backpressure? Never enough data collected/presented on these intercooler tests to answer the question. Power tracks with mass airflow (less inefficiencies) Have a higher temp but the same manifold pressure? You have less mass airflow and less cylinder pressure. Made the same power power to the flywheel though? Probably exhaust backpressure.? Whats the turbine speeds? DATA Richard!
The issue is that the heat exchanger is often undersized in people's air to water setups so even with a big intercooler they heat soak badly. It is also imperative that you have a fan on your heat exchanger, so when you figure out your configuration make sure you take that into acocunt.
What i found out on my BMW N54 engine with twin turbo and a aftermarket tune running the boost to around 20psi is that any intake temp over 110 degrees cause 2-3 degrees of timing retard which killed about 70-80 lbft. The issue with air to air on a street car is that you are almost always over 110 degrees AIT so you are always pulling timing. What I wanted to build was a air to water but use the A/C system like a Killer Chiller to keep the water really cold and the loss of power due to A/C was easily made up by not pulling timing. I live in Texas and any outside temp over 70 degrees would cause the AIT to be over 110 since the best ATA are about 20 degrees above ambient and pushing the AIT to stay above 110. Air to air is not ideal for a street car unless you like always giving up power. Sitting in traffic just causes more heat soak and you never get temps back down.
Love it! How about a test on the ice water? Or better yet test an AC compressor chilled unit like the dodge demon uses from OEM. I know you probably don't like to get specific on brands but there is a very popular kit made in Australia.
Air to water might be better for the street, you still need a radiator for it, but if you're style is only short power outputs (keeping inside the speed limit) you might get away with small core for cooling the intercooler water, this is because there is buffer effect in water, (termal capacity) And also the charge piping impact the turbolag, it's not only the pipes, but also the volume inside cooler. When you do turbo test like this, is there any way to dyno the turbo lag? Let's say you put the dyno to not go ower 3 or 4 trpm and on time scale get the engine slowly up on the rews, then floor it and see how fast the boost picks up? All the best and keep up the great work
Very true. He's not testing a closed loop water system. His water source is the dyno cell water. Most people only have small tanks and serious guys have actual cells full of ice.
ATW may have advantages in transient operations, space, minimizing charge piping, and depending on the application being able to easily cool below ambient temperature (ice in the expansion tank)
A general rule is 10deg temp with change 1% hp. In this case we should have seen a difference of only about 8hp. Nothing crazy but should have been seen in the comparison. Mystery. However, the lower charge temps should allow a touch more ignition timing when on pump gas where knock could be a limiting factor.
@@meetthecarolinas9638 That was the point I was trying to make, 1.4% (14 degrees) is nominal & is probably less than the margin of error for the dyno. Even if you gained the 8 HP by going ATW, you're not going to notice it from the driver's seat.
@@damonriddle1370 you'll absolutely feel it from the driver's seat, but it depends on your application. If you're banging off 1/8th or 1/4 miles you won't heat soak. Spend time on a road course, or pulling something up a hill and you'll quickly see the massive advantages of air to water.
it'll make more difference at higher boost levels. more timing with the lower air charge temps will tilt in the favor of air to water and make up for the pressure drop from the larger air to water tank.
So, I wake up at 3:30am and there are videos waiting for me to watch... Holdner and well, yeah the other one about the upcoming race on ppv with 20+ crown vics equipped with nitrous.
Definitely the timing is the reason there is no difference in power. Would love to see the same test but with optimized timing on the air to water setup.
Wow that's really interesting that goes against everything been told and read about temperature and Power. What your opinion would be the best option for a daily driver? Thanks again I learn something new every video I watch!
I agree with most people the delta in T wasn't enough but as also stated the Turbo was well within its effeciency Island too, push the boost I bet then you would see HP change... Richard Holdner love your tests separates all the BS from real HP makers! Also something I would like to see is measure the airflow from backside of ATA to see how much cfm is moving through also would like to see it on a typical car setup. I have ATW and there were two aftermarket choices one the that was wider and covered ie more surface area but most of it is covered by the bumper in addition to being in front of the radiator. So the one I picked sits in the airdam openeing and is thicker so surface area is less but not much. I've been trying to get logs from people who have other type because 1st thing I noticed was radiator coolant temps 10 degrees cooler and my charge air temp was 20 degrees colder and recovered faster especially at roll races IAT/CAC never gets above 20 degrees delta for 0-150 mph runs start at 10 degrees above ambient by the end of run 10 Delta increase. By the time I slowed down back to 10 lol.
You're my hero I love all the comparison work you do keep up the great work... now as for the difference between air to Air and air to water the only comparison I see is every 11 degrees is only 1% more power, it's not that great of a difference,. also the air-to-air probably has more tubing which helps to promote Cooling almost negating the advantages of air to water
We might not see a measurable difference in HP with the lower inlet temperature using identical fuel and timing maps. However the higher inlet temps will put the engine closer to detonation. When you are further from detonation you can tune for slightly leaner AFRs and go deeper in the timing map to produce more power. I think this is even more true when running higher inlet pressure where inlet temps rise significantly. Your thoughts?
Here are a few things I would be interested in seeing, 1. A2W with the turbo clocked, and minimized piping, I wonder if it would produce a faster response from the turbo. 2. ice water added to the comparison. 3. more data, I'd be interested to see the pressure drop across each core(boost into the intercooler vs boost out). I see quite a few comments about A2W being complicated, but I honestly think I prefer it to A2A for one big reason, it's actually easier to package in a car in most applications. with A2A, you are almost guaranteed to have to cut holes in the core support/grill to fit the intercooler, A2W, you can run the water lines through existing holes or even above/below the core support. the heat exhanger can be put anywhere, or be several in series or parallel. you also have the option of upgrading the system to improve performance without changing the induction piping, a larger HX core, or water pump can be added, or 2 pumps run.
From my understanding, the air temp doesn't matter near as much as the fuel temp. Between runs, when drag racers ice their manifold to get more power, what really is going on is the ice cools the fuel which is why the gain in power. Doesn't matter that the air charge cools because it's just heated back up as it's compressed, but the cold fuel chills the incoming air charge and cylinders.
@@richardholdener1727 At least that's what I learned from watching Engine Masters lol :) I wish I were closer to you guys because I'm building a 1.8 turbocharged ecotec engine out of my Chevy Cruze. Custom JE pistons, H-beam rods, big turbo gt3582 and shooting for 450+ whp. Uncharted territory, but a good lil foundation for a serious hp build because of the cast iron block and aluminum head with DOHC VVT. Thanks for all the great content. Your videos have helped a lot in furthering my knowledge. Thanks, Richard!
Based on what I'm understanding you to say a/w would probably work best for applications where there isn't a lot of wind speed such as tractor pull, mud racing, or rock crawling.
You could use the leaf blower for extra cooling, at the start of the vid, thanks Richard for the vids cheers from OZ STAY SAFE. PS your philosophy on engines are spot on.
I think it would be a more accurate test to have the dyno hold the engine at say 5500 rpms and run it there till everything stabilized then compare the numbers. Your actual intake temp is higher than indicated because of the lag in the thermocuples temperature measured response. Also things like probe position and probe direction vs airflow can effect the readings as well. As you say very hard to do an accurate comparison. On long pulls heat soak becomes a big problem. That is when an air to air usually shines as an air to water requires a water to air radiator to get rid of the heat at some point if you are running hard a long time so then it just becomes a bigger more complex air-air system. :-)
Hi Richard, if the intake temp is lower it should be more dense, therefor a more dense intake charge can allow more fuel and timing , more power, and still have the same target A/F ratio as the less dense, hotter intake charge? Yes.
Air to water in production cars show the advantage is turbo lag with heavy throttle modulation. Since you don't need piping running to the front of the car the charger can have a far shorter run to the heads. But in a drag race I don't think that would matter
Im gonna lean towards the air to air intercooler having less of a pressure drop, so the turbo is working less to make the set boost at the manifold,which should result in lower exhaust backpresure before the turbine.
I think its the other way around, ive always read w2a had way less pressure drop than air to air. Im sure you could get a inefficient w2a intercooler that had more drop then a really efficient a2a but apples to apples w2a are better at maintaining pressure they are also superior at drawing heat out of air.
Wouldn't the reason for the a2w be to get your charge cooler so you can widen your tuning window to add more timing? Would the change be drastic if you tuned each setup to its potential? Based on the different IAT's
Yep and that is the problem with alot of these dyno tests. They seem to think that if they keep everything the same, the results are a direct reflection on the thing being tested. Methanol Injection test was a big one.
Another thing to note for the average guy.. alot of heat exchangers for the a/w setups are almost as large as an intercooler itself. They come with fans attached and are easily as large as an A/C condenser... that's if you need one that doesn't heat soak 10 seconds into full throttle or if you are doing hot laps at the track.
@@richardholdener1727 hi mate, the cross section of the ATA is absolutely huge due to the tanks mounted on the long edges of the core (its the opposite way around on a bmw n54 intercooler) As for data, you mention all engine parameters were equal as was the power - this was dispite the charge temp difference. It's seems it takes more engine effort to push airflow past the WTA intercooler which looks to be a significantly less cross section than ATA core. What are your thoughts mate? 😉
I think that it is worth stating that the ATA in this test is definitely not the norm...that is a 50 row vertical flow intercooler. Unless you have a Mack truck, you aren't fitting that on anything. People get caught up on cooler numbers, but they don't realize you have to have the real estate under the hood to fit that monster and most don't buy/can't afford/ vertical flow intercoolers of this magnitude. That thing is the equivalent of a 4ft tall x 4" thick ebay cooler that most buy. Would love to see an ATA intercooler test.
I’d like to add later comment here. For reliability on pump fuel lower temps are better. I see loss of 30whp on the late model turbo cars on pump gas at a 120 iat vs 90 iat. Engines like this you need to see if more timing matters but push rod v8 are less sensitive to timing. This allows similar power. For example a late model turbo DI civic type r will only take 9 degree of timing vs pushrod v8 can see well over 30 degrees on pump fuel.
Water at the same temperature can absorb much more heat than air. Water has 900 times the density of air. So I would expect a slower ramp in temperature with the water to air intercooler. A power advantage for a better intercooler of any type depends on your need to run higher boost. At 10psi both intercoolers are more than sufficient for this application. If you had increased boost, the water to air intercooler might well support more power than the air to air intercooler.
When the air temps go down the engine will take more timing and make more power. Not changing the timing will produce the same power as the highest temp. Water injection can take more timing because there is still water droplets evaporating inside the manifold and compression cycle.
Richard, In tests like this one, I'd also like to see pre and post intercooler temps and pressure. It's really difficult to draw any reliable conclusions without that data. Could be that they were both the same pressure in the manifold, but possibly after a greater or lesser pressure loss across them. It would also be great to have the ambient air temp and dyno water temp logged too. Oh, and sustained RPM or long duration step testing to allow the temp sensors to stabilize. Thanks for the good conversation starter and again for not covering the RPM on the dyno graph with the commentary overlay
I am more interested in high boost 30+ psi where heat is a much bigger concern. I noticed the temps rose pretty high with the air to air intercooler which would limit the amount of boost you can safely run.
I like this test. I would imagine that the non change of power is possibly timing limit. It’s possible that you didn’t have enough timing to create a big enough cylinder temp that a 10-15 degree would matter. Another possibility is that the manifold itself had more heat in it than you could see while running the air to water. The fuel temperatures could have been hotter during afr to water inter cooler. Too many variables without getting manifold temperatures instead of just after the intercooler.
proper sizing and efficiency is more important than what type of intercooler you use. There are a few exceptions. I've tuned standing mile vehicles that go over 200. In one situation a customer had an ATA setup on his procharged C5. One a hot day his runs would start at 110 degrees and by the end of the run his temps would be over 200 degrees. Now, if he had an ATW setup he could have gotten his temps down to ~30 and if his intercooler was properly sized it wouldn't have risen much over that. In that situation the gains would have been extremely large. So I guess my opinion is, anything that is purpose built for short runs (1/4 to 2 mile) the ATW is the way to go. My personal car has a magnuson 2650R and I don't see any temp increases from 0-150, I've never seen that with an ATA.
All things sized correctly and equal. The advantage of the AtW over the AtA is keeping things cool all the time. As you. Seen with the Temps comparison. Those numbers would be exaggerated in a street car. My personal preference is always a AtW but an AtA would be just as good of choice on a Roadcoarse/circuit race car.
So you have convinced me I NEED a turbo, But I do not want to have anyone tune my junk. Have you ever thought about making videos about how to tune? I have the Holley Terminator, but my ride got t boned 2 months after getting it running so Im rebuilding and will start trying the tuning again but do not have any clue what to look for what the main goal is while tuning, Ill figure it out but Videos from the Man Richard, would be cool.
The low thermal mass and thermal conductivity of air explain the difference in IAT. It"s difficult to guess-timate the mass of each running across the intercoolers. Was the IAT signal from that probe also used by the dyno to calculate corrected power? That would explain the identical curves.
@@richardholdener1727 The deviation from expected results is too small to deduce anything from it. The squiggly temp curves don't inspire confidence in their accuracy. A 1/2 psi difference in charge pressure would explain it. A richer AFR on the ATA run could provide sufficient extra charge cooling to account for part of it. A sample size of one run with each set-up isn't exactly statistically valid either. Over-analyzing this without more, reliable data is pointless. Chalk it up to normal variations on the dyno.
I wonder if the slightly denser air of the AW isn't offset but the superior fuel atomization/mixing of the warmer AA charge. Also, I would love to see/hear more about the Silver State stuff.
Now what about a regular Air to water setup for a supercharger, no ice tank. I like the packaging of the Air to water much better because you can spread components out. The core is relatively small and soft lines can run anywhere, the heat exchanger isn’t very invasive for the cooling capacity they have and the water pumps are necessarily very large for the lower power levels. Would that not be better in hotter conditions and road racing “type of driving” than an oversized air to air intercoolers? Especially in warmer or higher elevation climates?
Richard, so the ATW intercooler is making the air cooler and thus more dense, but not my much. If we convert to absolute temperature (Kelvin), we get 108F = 315K and 122F - 323K. So the difference is pretty small. If we use some assumptions of 22.7 PSI (8 psi above 14.7 ambient), "moist" air and 50% humidity, we get 1.66 kg/m^3 for 122F and 1.71 kg/m^3 for 108F. Slightly more dense but not by much. Now! Can you please run this again but with Ice Water and charge air temperature before & after the intercooler? Thanks!
@@richardholdener1727 Because that shows you the absolute temperature. 122 isn't 13% higher than 108F (122/108), as the numbers seem to be. It's only 2.5% higher (323/315). And the relative temperature difference in Kelvin is what defines the relative density difference (ie. how much air you are cramming into the cylinders).
thats something id like to see remember back about 12- 15 years ago when the gm crate motor thing took off and they were doing that 572 big block chev was it wide open throttle for 12 or 24 hours something like that (im getting old ) but hey lets see some junkyard ls under boost wide open for 30 minutes or an hour (just to make it easier ) lets see some real ls goodness doing it tough for half an hour that will show us what a good combo realy is, you know its a good idea richard
we tossed around this idea after the first big bang motor to see how many pulls it could make at 1,000 hp, or how long it could stay loaded at that level
Also most will end up doing a 5.3, so how about possibly doing the forged 5.3 vs a stock 5.3 at a sustained HP level most could feasibly build for, and see when the stock 5.3 internals gives out, and how much MORE we can get out of a forged internals 5.3 WOOHOO!!
Science alert ⚠ : In kelven the temp difference was 315K vs 323k. A difference of only 2.5%. When looking at PV=nRT, a 2.5% change in 'T' isn't going to be earth shattering as far as things go.
science alert-the difference in IAT shouldn't be expressed in Kelven. 12 degree difference compared to 108 base is 11% or 9.8% compared to the 112 degree base
@@richardholdener1727 On that Mr. Holdener, I’m going to have to respectfully disagree 😉. But that’s what makes the world a great and diverse place. For completeness (and for everyone’s knowledge) : here is an overview of the reason that cooler intake air is more desirable. It’s because of the ideal gas equation: PV=nRT as I mentioned earlier. P = Pressure (Pa) V = Volume (m³) n = No. of moles (basically the mass of the gas in this case) R = Gas Constant (~8.315JK−1mol−1) T = Temperature (°K) All values are absolute values, not ‘gauge’ values (unless you have an absolute gauge😉, And are especially not US customary units 😉) So taking the example at hand: -P and V are fixed. P = 170kPa (10Psi gauge) and V = the volume of the intake manifold for simplicity. Its actual value is not important, since both are constant. -R is also constant by definition Which leaves ‘n’ and ‘T.’ Now in our case ‘n’ is the dependent variable, as it is dependent on ‘T’ which we have control over, via out choice of intercooling. Since both the Left and Right side of the equation must be equal: (Here’s the CRUX) as temperature rises, the mass of the gas must fall to maintain our desired pressure (170kPa) in our pre-defined volume (the intake manifold.) The inverse is also true (Colder air, requires more mass to maintain the same 170kPa in the intake manifold.) Since power output is dependent on the mass of air (Oxygen) contained within the cylinder, the cooler the intake charged at a fixed pressure, the more power you should make. Now as Richard (and others) have rightly noted, it is difficult to do back to back tests as: -turbine heat plays a roll, -Intercooler design (resistance across the core) effects results -Exhaust back pressure can be affected because of different Intercooler core resistance at the same intake manifold pressure. Turbo must work harder to push air through a crap cooler to make the same manifold pressure -> higher turbine drive pressure -> less shaft power at the crank. -Atmospheric changes (humidity and temperature) -Fuel temperature -The list can go on. Regardless, the test performed is very good and very insightful. I whole heartedly agree with Richard that it’s a matter of choosing the right tool (intercooler in this case) for the job. And that each design is best suited to differing aspects of motorsport. As a Circuit and Rally racer, Air-Air rules the roost 😉. I stand by my assertion that there is only a 2.5% relative difference in air mass entering the engine (Based on absolute values) in this test. Thus, this would fall well within normal test variance or within the dyno’s level of accuracy based on the number of uncontrollable variables (listed above.) Keep the video’s coming Richard. I’ll keep watching and learning from your wealth of test data. Regards Jordan
So 14degF or 10deC i think is not enough difference to gain a noticeable hp number on the dyno, i think there was a table equating an amount of degrees to hp somewhere
@Richard Holdener another great video. I come from an air cooled engine world and there is a common "trick" that I've also seen used on some ATA turbo cars, the "spray bar" where a cooling media (water, alcohol, or even NO2) is misted across the cooler core with the idea that it lowers temperature more than just air alone. We were all pretty sure it worked via the butt dyno, would this be something you would ever consider playing with to give some real world numbers?
"Inter"cooling implies cooling "between" two stages of compression, but "pre" cooling of the charge air would indeed increase it's density and should increase power.
With an air to air in a cooler, when sitting at the track and doing your burn out you’re not moving any air through that inner cooler which in turn is going to heat it up and cause heat soak so by the time you even make your pass down the dragstrip, you have high intake temps. Now with a air to water in her cooler you can have an ice box in the back and while you are staging or doing your burnouts you can already have your pump moving ice cold water through the inner cooler therefore you have low intake temps as soon as you launch
I think there was no change because the temp difference wasn’t that much. Also, with a turbo, it will compensate with air density from hot air with the waste gate and run nearly the same boost every time. If the compressor speed was static and the temp difference greater, I’m sure there would be a loss in boost and a loss in power.
So really the biggest Benefit of running the air to water intercooler is keeping the boost temp down and stop the fuel from detonation at higher boost levels. Thou in this test you didn’t see a gain but running it harder and more boost would definitely keep the fuel from getting too hot and starting to detonate. So it’s way more efficient than air to air. At that power level you don’t see knock in the tune. But if it was turned up there would be a definite gain with the air to water
I’d like to see this same test but on the fuel system instead of the charge air. Still run one charge cooler or the other, but adding an ice bucket with the incoming fuel line coiled up inside just before going to the fuel rail vs ambient temperature fuel. I’ve heard good things about using ‘cool cans’ on fuel lines but want to see it from the Holdener perspective.
In reference to ATA, would a larger intercooler help or at some point start hurting? At the beginning of the vid you said you had properly sized intercoolers, I think. Thanks keep it up!
You should also put a temp sensor in the intake manifold, I bet some of the latent heat of vaporization is providing more cooling after the intercooler like a carb would
What I take from this is the power range of a motor with air temperature has a large window where air temp changes but power stays the same. So qustion is how much of a temperature change do we need to see a change in power?
In drag racing- you only have to keep it cool for seconds. On a street car- heat soak is a problem. The water cooler still has to dump its heat through another radiator which relies on airflow. Eventually, the water will be heat soaked too
@@richardholdener1727 Heat soak can occur sitting at traffic lights after being on full boost for a few seconds. No airflow. The water temperature will rise. After driving off, It then takes minutes to chill if no further boosting. During that time, the intake temperatures are higher.
I’ve put tons of ice in my air to water Intercooler and it melts in about 30 seconds, it seems 90 degree air blowing on a heat exchanger just isn’t good enough to keep the ice cool enough especially with a turbo heating up the water as well.
How does differenentt ic core flows effect these different temps vs lack of differences in power? I would imagine that the air to air would flow better than the water to air unit in this case.
Could you run the same test, but instead of a drag race scenario, go to a track racing scenario with longer duration and getting on and off of the throttle?
Lots of comments. Not sure if this idea has been mentioned. Because of the boost reference location I think the intake temp could affect the amount of air molecules overall but doesn’t because of the regulated boost level. I think temp would limit what you could get away with on timing though. If you don’t adjust timing for intake temp, I wouldn’t expect a change.
In some cases maybeeee. I'm not a professional tuner but I think generally tuners just pull timing at high IATs like 130-140+ to prevent detonation especially on gas like 93 octane but they aren't adding timing at lower IATs as the IATs aren't a big factor in whats causing detonation in a boosted application. In this application the IATS are within range that timing wouldn't be pulled or need to change I don't think. Also Richard is really trying to show how this magical number of x% power gain from x degree intake temp change doesn't always hold true and all intercoolers can get the job done which sized appropriately. Love the video Richard!
i love it when closed captioning displays [music] during the dyno pull.
I mean, it's not wrong.
The sound is music to our ears, so I'd say it's accurate.
I find it even funnier when it says "applause" to the sound of a dyno pull
lol
Everything was the same so the power is the same. The reason I like the w2a is the extra ceiling. Our own car dropped from 56C @30lb in the traps with A2A to 20C with the W2a. Power was the same at first.. but with those low temps I was able to add more boost. A lot more boost. Maybe you should have added boost and timing till both intercoolers had the same outlet temp and then look at the hp difference.
That’s true but a2a intercoolers have a power rating, so putting in a larger intercooler would have brought it back down
Intercooler power rating is an airflow rating, not cooling capacity. You can install a straight piece of pipe that has the same horsepower rating.
The change in power is usually down to timing and knock sensitivity. Heat will make the engine more suseptable to knock as the boost and power go up.
Totally agree; was about to post the same. If the ATA setup was octane/ knock limited or tuned to the point that it was knock limited, you’d see the difference between the ATA and ATW intercooler. 14 degrees won’t be a huge difference, though.
Would’ve liked to see the ATW run with ice water to show POTENTIAL difference, too.
This is like watching Paul Harrell, but with engines.
"Please forgive the revving in the background..."
If you’re watching this channel you probably also watch Paul. They’re definitely cut from the same cloth.
The meat target would definitely make this more interesting.
@@krtacct 20 something bikini model?
I was just telling Dustin Lee that Paul Harrell is like talking engines with guys that know what they’re talking about. Literally 10 minutes before I watched this.
Thank you for posting videos on everything, everyone thinks about! Anytime I've got a question, I pull down the search menu for your channel, and whoop there it is ! Thanks Richard!
The air-water inter-cooler has a greater mass to transfer the heat from the intake charge. That's why its less susceptible to increased temperatures and the resultant heat soak.
Being that the test were run at WOT, I'm assuming the engine management system was deep into power enrichment for both runs which could have negated the higher IATs of the air-to-air intercooler, which one could argue that the air-to-water didn't need and robbing it of power. Also, given that both had the same ignition timing, it would have been safer to advance the timing on the air-to-water setup which had the cooler IATs before running into knock. There was more power left on the table, so to speak, that wasn't taken advantage of through tuning.
32 minutes at wot is a true test of a very well sorted driveline. Well done
Bah! I did that every morning, driving to work in my 42 HP Austin Mini back in the 70's.
I ran one of the first V2SQ supercharger kits on my 98S10SS. It didn't come intercooled and it didn't like anything over 8-9lbs and would see temps go north of 200F. I eventually added meth injection and it loved it. Went to 15lbs and with a 50/50 mix intake temps would stay around low 70s. With windshield wiper fluid around high 90s low 100s. Definitely worth it.
Absolutely love the videos keep up the great work! Would like to see a difference between the two on a max effort higher horsepower application and maybe throw ice water in the mix maybe at a 1000 horsepower 😀
I think a temperature probe on the outlet of the turbo and on the outlet of the intercooler would be nice to see. It would be interesting to see a graph of those two values and the intake air temp all plotted on one graph during a run.
Another idea for a dyno test would be an air to air intercooler shroud design. Corky Bell talks about necking down the ducting to the intercooler in his book.
Why’s the power the same? Because the IAT wasn’t different enough to have to change ignition timing to resist detonation and the difference in air density due to it was trivial.
Why haven't more people at least acknowledge your comment ...
I believe you are correct
I would have liked to have seen the dyno of the turbo without the intercooler.
Yes. I agree.
Basically the Boost curve would be identical. The difference is about 3% less hp around the curve entirely under boost with no intercooler do to the inefficiency as the heat in the inlet would be +165'F
Or even vs a carbed blow thru setup.
And with ice water in the air to water system also.
One advantage to ATW is a relatively short charge pipe. Also, packaging an ATW setup may be easier in a rear (or mid) engine car.
Thank you very much for this, Richard! This kind of information is extremely interesting and useful to guys who are building cars for dumbassery like I always am. :)
Was just about to go to sleep, gotta watch now
Is it possile that the air to air intercooler was slightly less restrictive than the water to air cooler thus compensating for the slight increace in charge temprature
No, you can’t match air speed across the core for the air to air. The air to water is using a pump with water pressure to force cool water across the core.
Exactly. So even if they were at the same boost at the intake, what was the pressure and temp before and after the intercooler? How about the backpressure? Never enough data collected/presented on these intercooler tests to answer the question.
Power tracks with mass airflow (less inefficiencies) Have a higher temp but the same manifold pressure? You have less mass airflow and less cylinder pressure. Made the same power power to the flywheel though? Probably exhaust backpressure.? Whats the turbine speeds? DATA Richard!
the pressure drop across both cores was identical-they were not restrictive at this power and boost level
The issue is that the heat exchanger is often undersized in people's air to water setups so even with a big intercooler they heat soak badly. It is also imperative that you have a fan on your heat exchanger, so when you figure out your configuration make sure you take that into acocunt.
Another fantastic test , thanks Richard
What i found out on my BMW N54 engine with twin turbo and a aftermarket tune running the boost to around 20psi is that any intake temp over 110 degrees cause 2-3 degrees of timing retard which killed about 70-80 lbft. The issue with air to air on a street car is that you are almost always over 110 degrees AIT so you are always pulling timing. What I wanted to build was a air to water but use the A/C system like a Killer Chiller to keep the water really cold and the loss of power due to A/C was easily made up by not pulling timing. I live in Texas and any outside temp over 70 degrees would cause the AIT to be over 110 since the best ATA are about 20 degrees above ambient and pushing the AIT to stay above 110. Air to air is not ideal for a street car unless you like always giving up power. Sitting in traffic just causes more heat soak and you never get temps back down.
thanks for these awesome and educational vids. i like how you do your experiments. btw which do you prefer, air to air or water to air coolers?
Love it! How about a test on the ice water? Or better yet test an AC compressor chilled unit like the dodge demon uses from OEM. I know you probably don't like to get specific on brands but there is a very popular kit made in Australia.
Air to water might be better for the street, you still need a radiator for it, but if you're style is only short power outputs (keeping inside the speed limit) you might get away with small core for cooling the intercooler water, this is because there is buffer effect in water, (termal capacity)
And also the charge piping impact the turbolag, it's not only the pipes, but also the volume inside cooler.
When you do turbo test like this, is there any way to dyno the turbo lag?
Let's say you put the dyno to not go ower 3 or 4 trpm and on time scale get the engine slowly up on the rews, then floor it and see how fast the boost picks up?
All the best and keep up the great work
Very true. He's not testing a closed loop water system. His water source is the dyno cell water. Most people only have small tanks and serious guys have actual cells full of ice.
Why no change in HP? It was only 14 degrees difference in temp, and that was only at the end of the pull. For simplicity's sake, I'd run air to air.
ATW may have advantages in transient operations, space, minimizing charge piping, and depending on the application being able to easily cool below ambient temperature (ice in the expansion tank)
A general rule is 10deg temp with change 1% hp. In this case we should have seen a difference of only about 8hp. Nothing crazy but should have been seen in the comparison. Mystery.
However, the lower charge temps should allow a touch more ignition timing when on pump gas where knock could be a limiting factor.
@@meetthecarolinas9638 That was the point I was trying to make, 1.4% (14 degrees) is nominal & is probably less than the margin of error for the dyno. Even if you gained the 8 HP by going ATW, you're not going to notice it from the driver's seat.
@@damonriddle1370 you'll absolutely feel it from the driver's seat, but it depends on your application. If you're banging off 1/8th or 1/4 miles you won't heat soak. Spend time on a road course, or pulling something up a hill and you'll quickly see the massive advantages of air to water.
it'll make more difference at higher boost levels. more timing with the lower air charge temps will tilt in the favor of air to water and make up for the pressure drop from the larger air to water tank.
So, I wake up at 3:30am and there are videos waiting for me to watch...
Holdner and well, yeah the other one about the upcoming race on ppv with 20+ crown vics equipped with nitrous.
That Cletus event will be super cool
Definitely the timing is the reason there is no difference in power. Would love to see the same test but with optimized timing on the air to water setup.
Both were already optimized
Hmmm, but it was the same timing on both setups? At 10:50 you said timing didn’t change.
Wow that's really interesting that goes against everything been told and read about temperature and Power. What your opinion would be the best option for a daily driver? Thanks again I learn something new every video I watch!
I agree with most people the delta in T wasn't enough but as also stated the Turbo was well within its effeciency Island too, push the boost I bet then you would see HP change... Richard Holdner love your tests separates all the BS from real HP makers! Also something I would like to see is measure the airflow from backside of ATA to see how much cfm is moving through also would like to see it on a typical car setup. I have ATW and there were two aftermarket choices one the that was wider and covered ie more surface area but most of it is covered by the bumper in addition to being in front of the radiator. So the one I picked sits in the airdam openeing and is thicker so surface area is less but not much. I've been trying to get logs from people who have other type because 1st thing I noticed was radiator coolant temps 10 degrees cooler and my charge air temp was 20 degrees colder and recovered faster especially at roll races IAT/CAC never gets above 20 degrees delta for 0-150 mph runs start at 10 degrees above ambient by the end of run 10 Delta increase. By the time I slowed down back to 10 lol.
You're my hero I love all the comparison work you do keep up the great work... now as for the difference between air to Air and air to water the only comparison I see is every 11 degrees is only 1% more power, it's not that great of a difference,. also the air-to-air probably has more tubing which helps to promote Cooling almost negating the advantages of air to water
We might not see a measurable difference in HP with the lower inlet temperature using identical fuel and timing maps. However the higher inlet temps will put the engine closer to detonation. When you are further from detonation you can tune for slightly leaner AFRs and go deeper in the timing map to produce more power. I think this is even more true when running higher inlet pressure where inlet temps rise significantly. Your thoughts?
Would have liked to seen a no intercooler comparison with the two intercoolers. Good job on the video.
Good stuff richard. Thanks for the content.
Motion Raceworks stated that this is not a HP issue this is a Keep the the pistons in the motor thing.
Here are a few things I would be interested in seeing, 1. A2W with the turbo clocked, and minimized piping, I wonder if it would produce a faster response from the turbo. 2. ice water added to the comparison. 3. more data, I'd be interested to see the pressure drop across each core(boost into the intercooler vs boost out).
I see quite a few comments about A2W being complicated, but I honestly think I prefer it to A2A for one big reason, it's actually easier to package in a car in most applications. with A2A, you are almost guaranteed to have to cut holes in the core support/grill to fit the intercooler, A2W, you can run the water lines through existing holes or even above/below the core support. the heat exhanger can be put anywhere, or be several in series or parallel. you also have the option of upgrading the system to improve performance without changing the induction piping, a larger HX core, or water pump can be added, or 2 pumps run.
From my understanding, the air temp doesn't matter near as much as the fuel temp. Between runs, when drag racers ice their manifold to get more power, what really is going on is the ice cools the fuel which is why the gain in power. Doesn't matter that the air charge cools because it's just heated back up as it's compressed, but the cold fuel chills the incoming air charge and cylinders.
thnx-cooling the fuel helps-cooler air helps even more
@@richardholdener1727 At least that's what I learned from watching Engine Masters lol :)
I wish I were closer to you guys because I'm building a 1.8 turbocharged ecotec engine out of my Chevy Cruze. Custom JE pistons, H-beam rods, big turbo gt3582 and shooting for 450+ whp. Uncharted territory, but a good lil foundation for a serious hp build because of the cast iron block and aluminum head with DOHC VVT.
Thanks for all the great content. Your videos have helped a lot in furthering my knowledge. Thanks, Richard!
Based on what I'm understanding you to say a/w would probably work best for applications where there isn't a lot of wind speed such as tractor pull, mud racing, or rock crawling.
You could use the leaf blower for extra cooling, at the start of the vid, thanks Richard for the vids cheers from OZ STAY SAFE. PS your philosophy on engines are spot on.
I’m glad I subbed great content !!!
Thanks for the sub!
I think it would be a more accurate test to have the dyno hold the engine at say 5500 rpms and run it there till everything stabilized then compare the numbers. Your actual intake temp is higher than indicated because of the lag in the thermocuples temperature measured response. Also things like probe position and probe direction vs airflow can effect the readings as well. As you say very hard to do an accurate comparison. On long pulls heat soak becomes a big problem. That is when an air to air usually shines as an air to water requires a water to air radiator to get rid of the heat at some point if you are running hard a long time so then it just becomes a bigger more complex air-air system. :-)
Short version: Road Race, air to air, anything shorter duration, air to water...
Water to air is better if you have a icebox but its dont last long before the heat melt the ice = good for drag racing
Hi Richard, if the intake temp is lower it should be more dense, therefor a more dense intake charge can allow more fuel and timing , more power, and still have the same target A/F ratio as the less dense, hotter intake charge? Yes.
Air to water in production cars show the advantage is turbo lag with heavy throttle modulation. Since you don't need piping running to the front of the car the charger can have a far shorter run to the heads. But in a drag race I don't think that would matter
Im gonna lean towards the air to air intercooler having less of a pressure drop, so the turbo is working less to make the set boost at the manifold,which should result in lower exhaust backpresure before the turbine.
I think its the other way around, ive always read w2a had way less pressure drop than air to air. Im sure you could get a inefficient w2a intercooler that had more drop then a really efficient a2a but apples to apples w2a are better at maintaining pressure they are also superior at drawing heat out of air.
I'd like to see you change the fuel and use ice to show the power advantage, also maybe nitrous on the ata love the videos, keep them coming
Wouldn't the reason for the a2w be to get your charge cooler so you can widen your tuning window to add more timing? Would the change be drastic if you tuned each setup to its potential? Based on the different IAT's
Yep and that is the problem with alot of these dyno tests. They seem to think that if they keep everything the same, the results are a direct reflection on the thing being tested. Methanol Injection test was a big one.
All true…and also the climate and ambient temperature matters. Too cold things are harder to start and get going, back fires on starting line,
Keeps air intake temps below 160 and all is good. Nothing to gain.
Another thing to note for the average guy.. alot of heat exchangers for the a/w setups are almost as large as an intercooler itself. They come with fans attached and are easily as large as an A/C condenser... that's if you need one that doesn't heat soak 10 seconds into full throttle or if you are doing hot laps at the track.
the water to air intercooler has a larger pressure drop - offsetting the cooler charge temp advantage. 😎
Correct, i would like to see a boost port on either side of the intercooler bridges to a boost gauge to see the pressure delta.
Not if the wastegate reference was coming from after the cooler... then the pressure at the throttle body will be the same either way.
W/A IC generally have lower pressure drop due to their relatively short and wide flow path.
how do you know the ATW had a larger pressure drop-you don't have that data
@@richardholdener1727 hi mate, the cross section of the ATA is absolutely huge due to the tanks mounted on the long edges of the core (its the opposite way around on a bmw n54 intercooler)
As for data, you mention all engine parameters were equal as was the power - this was dispite the charge temp difference. It's seems it takes more engine effort to push airflow past the WTA intercooler which looks to be a significantly less cross section than ATA core. What are your thoughts mate? 😉
I think that it is worth stating that the ATA in this test is definitely not the norm...that is a 50 row vertical flow intercooler. Unless you have a Mack truck, you aren't fitting that on anything. People get caught up on cooler numbers, but they don't realize you have to have the real estate under the hood to fit that monster and most don't buy/can't afford/ vertical flow intercoolers of this magnitude. That thing is the equivalent of a 4ft tall x 4" thick ebay cooler that most buy. Would love to see an ATA intercooler test.
GIVES YOU THE POTENTIAL TO MAKE MORE POWER WITH LOWER INTAKE TEMPS, MORE TIMING
Yeah add 3 degrees and try again
I’d like to add later comment here. For reliability on pump fuel lower temps are better. I see loss of 30whp on the late model turbo cars on pump gas at a 120 iat vs 90 iat.
Engines like this you need to see if more timing matters but push rod v8 are less sensitive to timing. This allows similar power. For example a late model turbo DI civic type r will only take 9 degree of timing vs pushrod v8 can see well over 30 degrees on pump fuel.
Water at the same temperature can absorb much more heat than air. Water has 900 times the density of air. So I would expect a slower ramp in temperature with the water to air intercooler. A power advantage for a better intercooler of any type depends on your need to run higher boost. At 10psi both intercoolers are more than sufficient for this application. If you had increased boost, the water to air intercooler might well support more power than the air to air intercooler.
When the air temps go down the engine will take more timing and make more power. Not changing the timing will produce the same power as the highest temp. Water injection can take more timing because there is still water droplets evaporating inside the manifold and compression cycle.
Richard, In tests like this one, I'd also like to see pre and post intercooler temps and pressure. It's really difficult to draw any reliable conclusions without that data. Could be that they were both the same pressure in the manifold, but possibly after a greater or lesser pressure loss across them. It would also be great to have the ambient air temp and dyno water temp logged too. Oh, and sustained RPM or long duration step testing to allow the temp sensors to stabilize.
Thanks for the good conversation starter and again for not covering the RPM on the dyno graph with the commentary overlay
I am more interested in high boost 30+ psi where heat is a much bigger concern. I noticed the temps rose pretty high with the air to air intercooler which would limit the amount of boost you can safely run.
Great test! What s480 where you running? What was the turbine side? Wheel/AR?
I like this test. I would imagine that the non change of power is possibly timing limit. It’s possible that you didn’t have enough timing to create a big enough cylinder temp that a 10-15 degree would matter.
Another possibility is that the manifold itself had more heat in it than you could see while running the air to water. The fuel temperatures could have been hotter during afr to water inter cooler. Too many variables without getting manifold temperatures instead of just after the intercooler.
Would like to See the boost go through atw to stabilize the temperaturen and then through the ata to sink it more
WOULD BE BETTER IF IT WENT ATA FIRST-THEN ATW
proper sizing and efficiency is more important than what type of intercooler you use. There are a few exceptions. I've tuned standing mile vehicles that go over 200. In one situation a customer had an ATA setup on his procharged C5. One a hot day his runs would start at 110 degrees and by the end of the run his temps would be over 200 degrees. Now, if he had an ATW setup he could have gotten his temps down to ~30 and if his intercooler was properly sized it wouldn't have risen much over that. In that situation the gains would have been extremely large. So I guess my opinion is, anything that is purpose built for short runs (1/4 to 2 mile) the ATW is the way to go. My personal car has a magnuson 2650R and I don't see any temp increases from 0-150, I've never seen that with an ATA.
I am going to a Meziere 55gpm pump on my roots air to water from a wp136 so I hope more gpm of water makes more power.
I would've liked to see what the number is without an intercooler
All things sized correctly and equal. The advantage of the AtW over the AtA is keeping things cool all the time. As you. Seen with the Temps comparison. Those numbers would be exaggerated in a street car. My personal preference is always a AtW but an AtA would be just as good of choice on a Roadcoarse/circuit race car.
So you have convinced me I NEED a turbo, But I do not want to have anyone tune my junk. Have you ever thought about making videos about how to tune? I have the Holley Terminator, but my ride got t boned 2 months after getting it running so Im rebuilding and will start
trying the tuning again but do not have any clue what to look for what the main goal is while tuning, Ill figure it out but Videos from the
Man Richard, would be cool.
The low thermal mass and thermal conductivity of air explain the difference in IAT. It"s difficult to guess-timate the mass of each running across the intercoolers.
Was the IAT signal from that probe also used by the dyno to calculate corrected power? That would explain the identical curves.
The IAT probe has nothing to do with dyno calibration-it doesn't change calibration based on IAT
@@richardholdener1727 The deviation from expected results is too small to deduce anything from it. The squiggly temp curves don't inspire confidence in their accuracy. A 1/2 psi difference in charge pressure would explain it. A richer AFR on the ATA run could provide sufficient extra charge cooling to account for part of it. A sample size of one run with each set-up isn't exactly statistically valid either. Over-analyzing this without more, reliable data is pointless. Chalk it up to normal variations on the dyno.
The difference in temp is heat soak. The results didn't differ because the test was ended before the heat soak could effect the outcome.
I wonder if the slightly denser air of the AW isn't offset but the superior fuel atomization/mixing of the warmer AA charge. Also, I would love to see/hear more about the Silver State stuff.
Because the peak charge temp differential was only 14f...that’s why the negligible power differential
Nice vid as always. Keep it up!
The difference is that you can adjust your timing and fuel map to take advantage of the cooler charge air.
I'm glad I didn't switch to atw and kept the ata. I also run water/meth injection.
Air to water for drag is also internal volume of the intercooler. Antifreeze and dryice is a sweet combo for lowest temp charge.
more like dry ice and isopropyl rubbing alcohol!
Now what about a regular Air to water setup for a supercharger, no ice tank. I like the packaging of the Air to water much better because you can spread components out. The core is relatively small and soft lines can run anywhere, the heat exchanger isn’t very invasive for the cooling capacity they have and the water pumps are necessarily very large for the lower power levels. Would that not be better in hotter conditions and road racing “type of driving” than an oversized air to air intercoolers? Especially in warmer or higher elevation climates?
air to water isn't the best choice for road racing
Richard, so the ATW intercooler is making the air cooler and thus more dense, but not my much. If we convert to absolute temperature (Kelvin), we get 108F = 315K and 122F - 323K. So the difference is pretty small. If we use some assumptions of 22.7 PSI (8 psi above 14.7 ambient), "moist" air and 50% humidity, we get 1.66 kg/m^3 for 122F and 1.71 kg/m^3 for 108F. Slightly more dense but not by much. Now! Can you please run this again but with Ice Water and charge air temperature before & after the intercooler? Thanks!
why convert to get a smaller %
@@richardholdener1727 Because that shows you the absolute temperature. 122 isn't 13% higher than 108F (122/108), as the numbers seem to be. It's only 2.5% higher (323/315). And the relative temperature difference in Kelvin is what defines the relative density difference (ie. how much air you are cramming into the cylinders).
thats something id like to see remember back about 12- 15 years ago when the gm crate motor thing took off and they were doing that 572 big block chev was it wide open throttle for 12 or 24 hours something like that (im getting old ) but hey lets see some junkyard ls under boost wide open for 30 minutes or an hour (just to make it easier ) lets see some real ls goodness doing it tough for half an hour that will show us what a good combo realy is, you know its a good idea richard
we tossed around this idea after the first big bang motor to see how many pulls it could make at 1,000 hp, or how long it could stay loaded at that level
Also most will end up doing a 5.3, so how about possibly doing the forged 5.3 vs a stock 5.3 at a sustained HP level most could feasibly build for, and see when the stock 5.3 internals gives out, and how much MORE we can get out of a forged internals 5.3 WOOHOO!!
Hey Richard I would love to see you run a Chevy Motown motor on the dyno.
Science alert ⚠ :
In kelven the temp difference was 315K vs 323k. A difference of only 2.5%.
When looking at PV=nRT, a 2.5% change in 'T' isn't going to be earth shattering as far as things go.
Good post, most people forget this.
science alert-the difference in IAT shouldn't be expressed in Kelven. 12 degree difference compared to 108 base is 11% or 9.8% compared to the 112 degree base
@@richardholdener1727 I have to agree with Science alert, you must use absolute temperatures.
@@richardholdener1727
On that Mr. Holdener, I’m going to have to respectfully disagree 😉. But that’s what makes the world a great and diverse place.
For completeness (and for everyone’s knowledge) : here is an overview of the reason that cooler intake air is more desirable. It’s because of the ideal gas equation: PV=nRT as I mentioned earlier.
P = Pressure (Pa)
V = Volume (m³)
n = No. of moles (basically the mass of the gas in this case)
R = Gas Constant (~8.315JK−1mol−1)
T = Temperature (°K)
All values are absolute values, not ‘gauge’ values (unless you have an absolute gauge😉, And are especially not US customary units 😉)
So taking the example at hand:
-P and V are fixed. P = 170kPa (10Psi gauge) and V = the volume of the intake manifold for simplicity. Its actual value is not important, since both are constant.
-R is also constant by definition
Which leaves ‘n’ and ‘T.’
Now in our case ‘n’ is the dependent variable, as it is dependent on ‘T’ which we have control over, via out choice of intercooling.
Since both the Left and Right side of the equation must be equal: (Here’s the CRUX) as temperature rises, the mass of the gas must fall to maintain our desired pressure (170kPa) in our pre-defined volume (the intake manifold.) The inverse is also true (Colder air, requires more mass to maintain the same 170kPa in the intake manifold.) Since power output is dependent on the mass of air (Oxygen) contained within the cylinder, the cooler the intake charged at a fixed pressure, the more power you should make.
Now as Richard (and others) have rightly noted, it is difficult to do back to back tests as:
-turbine heat plays a roll,
-Intercooler design (resistance across the core) effects results
-Exhaust back pressure can be affected because of different Intercooler core resistance at the same intake manifold pressure. Turbo must work harder to push air through a crap cooler to make the same manifold pressure -> higher turbine drive pressure -> less shaft power at the crank.
-Atmospheric changes (humidity and temperature)
-Fuel temperature
-The list can go on.
Regardless, the test performed is very good and very insightful. I whole heartedly agree with Richard that it’s a matter of choosing the right tool (intercooler in this case) for the job. And that each design is best suited to differing aspects of motorsport. As a Circuit and Rally racer, Air-Air rules the roost 😉.
I stand by my assertion that there is only a 2.5% relative difference in air mass entering the engine (Based on absolute values) in this test. Thus, this would fall well within normal test variance or within the dyno’s level of accuracy based on the number of uncontrollable variables (listed above.)
Keep the video’s coming Richard. I’ll keep watching and learning from your wealth of test data.
Regards
Jordan
So 14degF or 10deC i think is not enough difference to gain a noticeable hp number on the dyno, i think there was a table equating an amount of degrees to hp somewhere
I drag race alot and i always say who needs an intercooler when you have nitrious oxide?
Water transfers heat 25 time faster than air.
Reference your Dyno test with the fan.
@Richard Holdener another great video. I come from an air cooled engine world and there is a common "trick" that I've also seen used on some ATA turbo cars, the "spray bar" where a cooling media (water, alcohol, or even NO2) is misted across the cooler core with the idea that it lowers temperature more than just air alone. We were all pretty sure it worked via the butt dyno, would this be something you would ever consider playing with to give some real world numbers?
I tested the cooler ring on an ATA
@@richardholdener1727 very cool of you to respond. Now I definitely have a reason to go through the rest of your videos, not like I wasn't anyway.
Wow!!!! 32 minutes WOT. That was one hell of an engine to hold up to that kind of punishment. What was the highest sustained rpm Richard?
less than 6000 rpm
No biggie. Honda School required full throttle for a hour after you assemble an engine or FAIL!
dielauwen a Honda is not a pushrod engine and can sustain high rpm over long periods.
OK I've got one for you Richard, how about a test of N/A versus N/A air to water intercooled.
Pointless, nothing to cause adiabatic heating = no need for intercooling...
"Inter"cooling implies cooling "between" two stages of compression, but "pre" cooling of the charge air would indeed increase it's density and should increase power.
@@fascistpedant758 not worth the weight or complexity...
@@YZFoFittie One lb. of ice could cool enough air for a 10 sec. pass with a 600 HP engine by ~50* F. Charge density would increase by almost 10%.
@@fascistpedant758 nope...
With an air to air in a cooler, when sitting at the track and doing your burn out you’re not moving any air through that inner cooler which in turn is going to heat it up and cause heat soak so by the time you even make your pass down the dragstrip, you have high intake temps. Now with a air to water in her cooler you can have an ice box in the back and while you are staging or doing your burnouts you can already have your pump moving ice cold water through the inner cooler therefore you have low intake temps as soon as you launch
Wonder what would be the difference of adding an ice box to the air to water?!
it makes more
I think there was no change because the temp difference wasn’t that much. Also, with a turbo, it will compensate with air density from hot air with the waste gate and run nearly the same boost every time. If the compressor speed was static and the temp difference greater, I’m sure there would be a loss in boost and a loss in power.
Volume, cooler air being more dense would need to be adjusted for boost to match the air to air.
So really the biggest Benefit of running the air to water intercooler is keeping the boost temp down and stop the fuel from detonation at higher boost levels. Thou in this test you didn’t see a gain but running it harder and more boost would definitely keep the fuel from getting too hot and starting to detonate. So it’s way more efficient than air to air. At that power level you don’t see knock in the tune. But if it was turned up there would be a definite gain with the air to water
There is probably slightly more of a flow restriction thru the ATW. You would need to test pressure drop thru both aftercoolers.
we did
I’d like to see this same test but on the fuel system instead of the charge air. Still run one charge cooler or the other, but adding an ice bucket with the incoming fuel line coiled up inside just before going to the fuel rail vs ambient temperature fuel. I’ve heard good things about using ‘cool cans’ on fuel lines but want to see it from the Holdener perspective.
No sanction on public streets lol
In reference to ATA, would a larger intercooler help or at some point start hurting? At the beginning of the vid you said you had properly sized intercoolers, I think. Thanks keep it up!
we've run over 1000 hp with both of these coolers
You should also put a temp sensor in the intake manifold, I bet some of the latent heat of vaporization is providing more cooling after the intercooler like a carb would
What I take from this is the power range of a motor with air temperature has a large window where air temp changes but power stays the same. So qustion is how much of a temperature change do we need to see a change in power?
In drag racing- you only have to keep it cool for seconds. On a street car- heat soak is a problem. The water cooler still has to dump its heat through another radiator which relies on airflow.
Eventually, the water will be heat soaked too
only if you are in boost 100% of the time you drive-which no one does
@@richardholdener1727 Heat soak can occur sitting at traffic lights after being on full boost for a few seconds. No airflow. The water temperature will rise. After driving off, It then takes minutes to chill if no further boosting.
During that time, the intake temperatures are higher.
I’ve put tons of ice in my air to water Intercooler and it melts in about 30 seconds, it seems 90 degree air blowing on a heat exchanger just isn’t good enough to keep the ice cool enough especially with a turbo heating up the water as well.
flow restriction on the water to air intercooler offsetting the temperature benefit.
there is almost no flow restriction on either of these coolers at this power level-made 2X this power with both
3% density change could be offset by 0.5psi, not 'overly restrictive' just enough to be annoying. :)
thanks for the cool content.
Colder is less detonation prone. Without more timeing its diminishing returns.
How does differenentt ic core flows effect these different temps vs lack of differences in power? I would imagine that the air to air would flow better than the water to air unit in this case.
the pressure drop was the same and we have made over 1000 hp with both of these
Could you run the same test, but instead of a drag race scenario, go to a track racing scenario with longer duration and getting on and off of the throttle?
Lots of comments. Not sure if this idea has been mentioned. Because of the boost reference location I think the intake temp could affect the amount of air molecules overall but doesn’t because of the regulated boost level. I think temp would limit what you could get away with on timing though. If you don’t adjust timing for intake temp, I wouldn’t expect a change.
that extra 14* of IATs temps allows more timing yea?
In some cases maybeeee. I'm not a professional tuner but I think generally tuners just pull timing at high IATs like 130-140+ to prevent detonation especially on gas like 93 octane but they aren't adding timing at lower IATs as the IATs aren't a big factor in whats causing detonation in a boosted application. In this application the IATS are within range that timing wouldn't be pulled or need to change I don't think. Also Richard is really trying to show how this magical number of x% power gain from x degree intake temp change doesn't always hold true and all intercoolers can get the job done which sized appropriately. Love the video Richard!
@Barge Arse Did he mention the knock stuff.. I may have missed it.