Bored to death with a centrifugal supercharger? Never! I haven't seen one of these things put onto a model engine, and it's super badass! You're so close man! Don't give up!
100% agree, don’t give up on the supercharger! Also agree with some of the other comments, possibly EFI? maybe a team up with a channel that can produce something on RasberryPi etc 🧐
@@_Mav Trust me, you wouldn't want to use a Raspberry Pi (SBC) for any engine application. A microcontroller (Ironically, the Raspberry Pi Pico could be used) is what you want.
@@crenn6977 just saw the video and at the end, some sort of fuel injection, even if it's just somet to adjust on the fly as the engine revs. Not EFI, "M (manual) FI" lol. Could this little thing have run away boost? Lol. Alright Johnny, time for that micro blow off valve 😬. How would you solve the EFI if not a small computer controlled fuel injection @crenn6977? I'm legitimately curious because Raspberry Pi popped into my head as well.
Well at this scale a small imperfection in manufacturing is very unforgiving. On an LS3 these flaws would lose maybe 5 to 10 HP over the stock 430, but on this, for like 1 HP it could stand to lose perhaps a quarter HP or so at the worst. So for an LS being a full size motor, that's between 1 to 2 percent power loss, but on this tiny motor that's a 25 percent loss in power. And with so much air flowing between the valves and the valve seats at 12k RPM before the lapping, it was losing a lot of potential power especially since its rated to reach 16k RPM (it is a Toyan L200). So with that defect fixed and even made better than stock, it likely makes somewhere around 1.25 HP without the supercharger and perhaps 3 or more with the supercharger once the AFR is tuned right with the 10 to 1 pulley.
Watch where he points lazer when he checks rpm. He is getting more rpm the second reading because he checks it closer to crankshaft. Lapping valves will increase efficiency and power but not by 4,000 rpm
Jacob Credle you might be confused, the rpm of a rotating body does not change depending where you measure it. A wheel spinning at 60rpm is spinning at 60rpm no matter where you measure it
Nah dude I'm not bored at all! I was literally waiting for this video to come out cause it's so cool and uncommon! You make me want to get a pocket nc and a 3d printer so that I can mess around with these little motors!
I had a PocketNC for a little while, but since moved up to a full size 5 axis machine. But that’s only because my dad and I have a machine shop, and the PocketNC couldn’t keep up. It was a great little machine though, a great tool to learn 5 axis milling, and perfect for hobbyists.
Watch where he points lazer when he checks rpm. He is getting more rpm the second reading because he checks it closer to crankshaft. Lapping valves will increase efficiency and power but not by 4,000 rpm
@@jacobcredle4807 Yes the laser is further out the second time, but the engine is revving noticeably higher, by the sound pitch it's making. I don't really know much about this kind of laser tachometer, as I've never used one, but if it counts revolutions, it should not matter how far out he checked it. The flywheel/pulley is spinning the same RPM along it's entire radius. It's the pulley speed that changes along it's radius, as the further from the centre, the further it needs to move for the same RPM. So provided the tachometer can somehow know when a complete revolution has been made, it shouldn't matter where the reading was taken. If it was a tachometer which works out the revolutions by measuring speed at a certain point on the radius, then it would matter. Like I said, I don't know how this type of tachometer works, usually he uses a tachometer which works by using a piece of reflective tape that reflects the laser, so allowing the tacho to count a revolution. I didn't see him put the tape on this time. Either it's a new type of laser tacho, or he didn't film the application of the tape.
to check power gains, you could always run the engine to an electric generator, see how much electricity it makes with and without the forced induction.
I was watching Smarter Everyday's video on power generation the other day, and he had a mini generator attach to a drill to show the effects of rotation speed on frequency loading. He also showed the difference of unconnected poles versus connected poles of said motor. In theory, you could create a load cell of resistors and use either a dmm or even a killawatt type device measure the output of the motor.
wait wth, valve lapping gave you a 25% increase in RPM?! there was that much pressure loss due to inconsistencies?! that is crazy! I love these videos!!
You have to use a geared ratio otherwise you cant get the charger to spin fast enough to produce enough positive air pressure. The crank might spin at 16,000 rpm now, but that charger is probably spinning over 110,000 rpm with the 1:10 pulley used here. With the 8.5 he was at 90,000 at .6 psi.
The problem is, the fuel isn't being pushed into the carb like the fuel tank is designed to do. The nipple on the lid of the gas tank is supposed to be connected to a source that can supply positive air pressure.
I’m not bored of this, I’m constantly amazed at what you are capable of designing and engineering and I watch in awe at the scale you work at, keep trying buddy I’m sure you’ll figure it out
I belive the reason it was running strange is due to fuel accumulation, fuel is sitting in the bottom of the compressor housing and when it's finally drawn into the engine it's causing your running issue.
I was thinking maybe the carburetor throat was too small and when the engine revs up a strong vacuum forms which begins pulling more fuel through the jet which revs it up more until it begins running lean and then it slows down and repeats.
Fuel accumulating in the compressor could be it, I was thinking that the intake manifold wasn't distributing fuel evenly as it's not well atomized by that point.
Never bored of your channel. Love the lapping and valve work. Positive increase. Racking my brain as to why the intermittent idle and why the needle valve has no affect on the flow. Could be pulling air through the SC bearings. Great Vid 👍🏼
I hardly ever give my full attention to TH-cam in general but your videos bring me to the table, I love how detailed you are with everything it’s amazing!
Adding a pressure bypass when throttle closes may help. Recirculating the pressure back to the intake of the supercharger, this would work best with the blow through design and relieve the compressor loading at idle.
Never bored with this content! I had a OS CZ .12 on my RC10 GT back in the day and it was all fun and games until the throttle stuck on my laneway and decided to end its life.
A little tip with boost gauges that like to shake or flutter. Stuff a piece of clay with a wd40 straw (the tiny red ones) through the middle into the pipe used to feed to gauge. The gauge will be slightly laggy (unoticably) but a lot smoother and more accurate. I had to do it on my car's one 😆
@@benjamindavidson632 yeah I saw the filters but they either seemed too cheap or too expensive 😆 had some milliput and a wd40 straw laying about so improvised 😆
@@MaNNeRz91 Yep RC filter, resistor and capacitor. The restriction is the resistor, and the pipe&gauage volume is a capacitor. Use to do this on boucing pressure transducers mounted too close to a pump set. Even just a length of plastic pipe with a crimp/bend in it works.
@@yeahright3348 I never thought about it as an electronic component before but that does make sense. Kind of like the bottle neck explanation for capacity and resistance. (I'm shit at electronics though.. I can repair stuff but I have no clue about working out current and amps)
Love your engine build and tune series. That engine is a PITA to tune and one of the reasons why I went from nitro engines to 2 stroke petrol 1/5th scale rc. You're ingenuity and ability to make things keeps it interesting.... Keep these videos coming.
Next stiffer valve springs and high duration/lift camshaft for 20000rpm. (and supercharger ofc) Maybe oil system upgrade. Soon the whole engine will be diy upgrades lol. Great video keep them coming!
Yeah, I've really been wondering if the camshaft has much of any tuning ground into it at all. Not really familiar enough, but my immediate guess would be that (like the rough machined valves) it's only meant to be good enough to let the engine run as a "functional model".
That valve lift is pretty small, how close are the valves springs to binding? You might be able to make rockers with a more aggressive rocker ratio to gain more lift which will also help with higher rpm.
@@henryarrington3446 overlap isn't always a bad thing in forced induction, especially in high revving engines. The duration of the overlap shouldn't change though, as without altering the cam profile, although the curtain area/time will be greater, the actual number of degrees per revolution that overlap exists will be the same. If boost drops it'll probably because the intake valves are exessively restrictive. Boost is a means to an end, if you reduce a restrictive valve you may drop boost, but if it means more air actually fills the cylinder then that's actually a beneficial drop.
@@17473039 your right I guess I worded it wrong. Overlap timing would be the same. But the valves would be open more during overlap. There is probably a lot of overlap in that engine to make it easy to start. I don’t know if it’s a flat tappet or roller lifters but if flat tappet you can’t get very aggressive on open and closing of valves. So builders have to put up with a little more overlap to get more duration/lift.
@@henryarrington3446 my guess is that being as cheap as it is, the cam probably acts directly on the rocker so it would act somewhere between the two. There is potential to advance the cam slightly so the intake valve close sooner so piston is closer to bdc when the intake valve closes, and rely on the supercharger flow and the overlap to help cylinder clearing on the exhaust stroke.
Don't quit you are just getting started! 3 tips, 1 I think a blow thru with a better carb is in order, 2 use a fluid filled gauge with a restriction in the line, and 3 make a large plenum on the manifold. If you look at what people have done for turbo's on small engines they need a "boost capacitor" basically it's a larger plenum for holding air to dampen the massive changes in pressure caused by low cylinder count.
@@LM-uz4pr Valve leak could actually be an issue that Johnny should inspect for. The valve springs weren't designed to hold positive intake pressure so the boost might be forcing air through them when they are supposed to be closed.
@@iNubAlert That's true for naturally aspirated cars. In the case of forced induction valve float can also occur when the valve springs are not stiff enough and the sheer air pressure generated by the supercharger/turbocharger manages to push the valves open
I think the shaky gauge had more to do with there still being compression leaking into the intake. Same as if you've ever tried reading vacuum on an engine with a bent or overtightened intake valve. Could just be an RC engine issue ... I've never built a 16K rpm engine ... there could be all kinds of overlap on that cam for all I know.
Iv seen people do this on small motors like for go-carts you need to use a carb with a butterfly not a slide throttle. I dont know why but it just works
It looks like your only tuning the high end needle? There’s a low end needle on the side of the carb as well. You need to tune the high end first to get peak rpm. Then the low end to get good idle and transition. Also going over to electronic ignition and petrol/gas where it auto advances the timing might help 😊
What was going on there sounded a lot like a vacuum leak to me than a tuning issue. Or maybe some weird interaction between the carb and the supercharger causing an odd vacuum signal. Using an elbow between the carb and the supercharger might not have been the best plan. the more complicated the path between the carb and the engines vacuum the more wonky things get. I once ran what I thought was a pretty simple routing of a flexible (but very stiff) tube between the carb and the engine of my two stroke, and found the engine was virtually untunable. it always ran like trash. Then I eliminated the tube and mounted it as direct as possible, instantly found the right jet, and now it runs flawlessly. And yes I realize this is a 4 stroke of sorts, but these principals do still apply. A carb is a carb. (at least when it comes to 2 and 4 strokes-)
I think fuel is getting somewhere in your supercharger system, and tgan fuel gets clogged up at one place and than it gets realeased so it gets more fuel in different times. Thats why it doesnt run smoothly
The power increases slowy or no power increased, reason of the existence of Intercoolers doesn't matter its supercharger, turbo or centrifugal turbo. In case of supercharged engines the cooling is down to the compressor before enters the engine, it's watercooled by a second radiator as intercooler, this also applies in centrifugal turbos used commonly in bikes.
I've always heard draw-through setups are a bit problematic because in the case of unevaporated fuel in the intake (if you run the engine too rich), the droplets could damage the spinning compressor and with those high rotationnal speeds, damage the blades, Is that true?
@@jakehartung3655 miniature engines are not airplane engines. The relative size of raindrops to an airplane turbine is miniscule compared to the fuel droplets on a miniature supercharger like this. Not to mention the materials used in airplane engines, the maintenance intervals involved in its operation, and the budgets of airline companies.
turbo surge is when it is trying to force air into the engine but the engine cannot accept any more air which causes the forced air thats being delivered to make its way back into the turbo's outlet and that is what makes that stustustu sound. theres no way the turbo is maxing out at idle. The idle is inconsistent because there are only two pistons so in between combustion cycles between the two cylinders there are no other pistons moving up and down to keep a steady delivery of air flow to keep the turbo spinning at a steady rate which at that point the whole cycle repeats itself.
Johnny, my man, you think we are bored to death with this thing? Boy are you wrong, there are 3 main reasons people watch these amazing videos of yours: 1-they are incredibly relaxing, 2-watching you make those parts and seeing how good of an engineer and craftsman you are is just incredible (btw, do you ever plan on uploading some videos where you teach us what you do to make these incredible machines of yours and how you do it?), and finally, 3-because watching these things work is, simply put, exciting. What I mean to say is, there is no project of yours, made in your style, that could ever bore us.
Keep up the awesome work!! So close to the Holy Grail so don't give up. Try finding an oil damped gauge cuz what is killing the gauge is needle oscillations ( it's moving way too fast). Years ago I ran across a book dealing with artificial boost for internal combustion engine design when I was playing around with turbo design for my bikes trying to eliminate most of the turbo lag. If you can find it, or something similar, that may help. Just keep at it cuz it is fascinating to watch you work. You have a talent that most don't. Can't wait to see you begin porting and stroking it (hint, hint).
Duuuude that little torque tool is freaking sweet, didn't even know they made one like that. This guys shop must be a wet dream for hobbyists, I mean just his little 5 axis is 5 grand but his skill is on another level!
I absolutely love this project! If it were me personally, I’d go back to blow through, keep your current pulley ratio to spin it fast enough, and run your fuel pressure tap from the intake tube between the blower and the carb. That way it should increase fuel pressure on a 1:1 ratio to boost pressure. You may also find that you need a stiffer valve spring. Even with such low boost, there’s still a good possibility that it’s blowing the valve off the seat and making it run erratic. Please don’t give up on it yet!
to prevent the gauge from being damaged and giving erratic readings ..... us a long length of pipe between the manifold and the gauge.... at the manifold end place a restriction in the pipe, a bush with a 0.1mm hole in it, this will damp the response of the gauge and give the gauge a longer life span .. nice work... cool project
It should not be mechanical to begin with. Theres wayyyy too much fluctuation and its jamming it up. This will happen in any situation which is why ALLLLLLL boost gauges are digital.
Awesome video, quick side note about the pressure gauges you were using. They made fluid-filled gauges that prevent the needle from jumping everywhere under fast changing conditions (and helps them not become stuck as a result) as with the slight resistance of the fluid, it makes the needle show the 'average' pressure compared to the 'instantaneous' pressure.
I'm was and will never being bored see your tests and research! Don't hesitate to continue In this case due to exhaust smoke I could say the fuel is clearly not normally carrying to engine. The engine have it in excess when you open throttle and compressor puzch the "heavy" oil+fuel to engine. If methanol is easy to transport on the air of your supercharger, oil that's take part of fuel could not be follow a such long tubing before engine I think your problem is here. Solution is hard but probably you need to separate air throttle and fuel Install a fuel sprayer as near as possible to valve and a simple air carb where you want.
Though I am far from bored with the centrifugal supercharger, I'm beyond geeked to see you do some kind of positive displacement rig. I'm guessing you'll go with a Roots-style setup, but whatever it is, I know it's going to be dang cool. Good luck! Can't wait to see it!
Bored to death with a centrifugal supercharger? Never! I haven't seen one of these things put onto a model engine, and it's super badass! You're so close man! Don't give up!
100% agree, don’t give up on the supercharger! Also agree with some of the other comments, possibly EFI? maybe a team up with a channel that can produce something on RasberryPi etc 🧐
This
@@_Mav Trust me, you wouldn't want to use a Raspberry Pi (SBC) for any engine application. A microcontroller (Ironically, the Raspberry Pi Pico could be used) is what you want.
@@crenn6977 maybe just add fuel pump?
@@crenn6977 just saw the video and at the end, some sort of fuel injection, even if it's just somet to adjust on the fly as the engine revs. Not EFI, "M (manual) FI" lol. Could this little thing have run away boost? Lol. Alright Johnny, time for that micro blow off valve 😬. How would you solve the EFI if not a small computer controlled fuel injection @crenn6977? I'm legitimately curious because Raspberry Pi popped into my head as well.
I wouldn't have expected a difference so big just from lapping the valves....
The sound difference alone is pretty incredible!
Well at this scale a small imperfection in manufacturing is very unforgiving. On an LS3 these flaws would lose maybe 5 to 10 HP over the stock 430, but on this, for like 1 HP it could stand to lose perhaps a quarter HP or so at the worst. So for an LS being a full size motor, that's between 1 to 2 percent power loss, but on this tiny motor that's a 25 percent loss in power. And with so much air flowing between the valves and the valve seats at 12k RPM before the lapping, it was losing a lot of potential power especially since its rated to reach 16k RPM (it is a Toyan L200). So with that defect fixed and even made better than stock, it likely makes somewhere around 1.25 HP without the supercharger and perhaps 3 or more with the supercharger once the AFR is tuned right with the 10 to 1 pulley.
@@Avetho 3 HP from an engine this size would be amazing to see in action
Watch where he points lazer when he checks rpm. He is getting more rpm the second reading because he checks it closer to crankshaft. Lapping valves will increase efficiency and power but not by 4,000 rpm
Jacob Credle you might be confused, the rpm of a rotating body does not change depending where you measure it. A wheel spinning at 60rpm is spinning at 60rpm no matter where you measure it
I can assure you, we are FAR from being "bored" with this project. It's incredible to watch the process. I LOVE this stuff man
What's this "we" shit, you got a mouse in your pocket?? 😜
we also want bigger pulleys
"danger to manifold"
Careful man or your floor pan will blast out
For that he should put an eclipse body on it
Mate, that comment deserves to be no.1!
@@azzz..6 See but then it’ll randomly spin out before it finishes any races
@@dtsnjsn6101 lol
it's plastic, he can lose as many he can without sparking lol
Nah dude I'm not bored at all! I was literally waiting for this video to come out cause it's so cool and uncommon! You make me want to get a pocket nc and a 3d printer so that I can mess around with these little motors!
Been thinking building cnc because yt videos have proven me I need one :D
Me too
I had a PocketNC for a little while, but since moved up to a full size 5 axis machine. But that’s only because my dad and I have a machine shop, and the PocketNC couldn’t keep up. It was a great little machine though, a great tool to learn 5 axis milling, and perfect for hobbyists.
Once again, awesome work. You must be a wizard. Great skills mate!
wizard? nah, just hard work and big brain 😉
Watch where he points lazer when he checks rpm. He is getting more rpm the second reading because he checks it closer to crankshaft. Lapping valves will increase efficiency and power but not by 4,000 rpm
@@jacobcredle4807 Yes the laser is further out the second time, but the engine is revving noticeably higher, by the sound pitch it's making. I don't really know much about this kind of laser tachometer, as I've never used one, but if it counts revolutions, it should not matter how far out he checked it. The flywheel/pulley is spinning the same RPM along it's entire radius. It's the pulley speed that changes along it's radius, as the further from the centre, the further it needs to move for the same RPM. So provided the tachometer can somehow know when a complete revolution has been made, it shouldn't matter where the reading was taken.
If it was a tachometer which works out the revolutions by measuring speed at a certain point on the radius, then it would matter.
Like I said, I don't know how this type of tachometer works, usually he uses a tachometer which works by using a piece of reflective tape that reflects the laser, so allowing the tacho to count a revolution. I didn't see him put the tape on this time. Either it's a new type of laser tacho, or he didn't film the application of the tape.
It might be sucking air throught your supercharger bearings if they arent sealed.
@@jacobcredle4807 that's not true, it reads the reflective tape once per revolution. It doesn't matter where the tape is.
to check power gains, you could always run the engine to an electric generator, see how much electricity it makes with and without the forced induction.
I was watching Smarter Everyday's video on power generation the other day, and he had a mini generator attach to a drill to show the effects of rotation speed on frequency loading. He also showed the difference of unconnected poles versus connected poles of said motor. In theory, you could create a load cell of resistors and use either a dmm or even a killawatt type device measure the output of the motor.
wait wth, valve lapping gave you a 25% increase in RPM?! there was that much pressure loss due to inconsistencies?! that is crazy! I love these videos!!
No way you've bored us with that. I love the supercharger setup. Just wished you would get it to work. Mount it straight off the front on the crank!
You have to use a geared ratio otherwise you cant get the charger to spin fast enough to produce enough positive air pressure. The crank might spin at 16,000 rpm now, but that charger is probably spinning over 110,000 rpm with the 1:10 pulley used here. With the 8.5 he was at 90,000 at .6 psi.
@@faulcun Dude, 16,000x10:160,000 supercharger revolutions (1:10)
@@darianistead2239 yep you right lol. Wasnt mathing
these replies are big brain, meanwhile i cant even figure out minecraft redstone lmao
I suspect your problem is a vacuum leak in the supercharger at the end of the video. I've seen that meany times before. Thanks for the great video.
yes I think through the ceramic bearings
The problem is, the fuel isn't being pushed into the carb like the fuel tank is designed to do. The nipple on the lid of the gas tank is supposed to be connected to a source that can supply positive air pressure.
I’m not bored of this, I’m constantly amazed at what you are capable of designing and engineering and I watch in awe at the scale you work at, keep trying buddy I’m sure you’ll figure it out
You have NOT bored us sir! You make us all aspire to have even half the skill you have. This is one of the best projects I’ve seen
I belive the reason it was running strange is due to fuel accumulation, fuel is sitting in the bottom of the compressor housing and when it's finally drawn into the engine it's causing your running issue.
I was thinking maybe the carburetor throat was too small and when the engine revs up a strong vacuum forms which begins pulling more fuel through the jet which revs it up more until it begins running lean and then it slows down and repeats.
I think a different style carburetor is in order.
Fuel injection is the way to go. I wonder if they make fuel injectors that small.
Fuel accumulating in the compressor could be it, I was thinking that the intake manifold wasn't distributing fuel evenly as it's not well atomized by that point.
@@dolsn173 Yeah, that's my thought too, asking atomized fuel to follow that path and stay atomized is a big ask.
I’ve never clicked so fast
Johnny this series is super fascinating. I'm always amazed by what you're able to acchieve with this engine. PLEASE continue to upgrade it :D
Never bored of your channel. Love the lapping and valve work. Positive increase. Racking my brain as to why the intermittent idle and why the needle valve has no affect on the flow. Could be pulling air through the SC bearings. Great Vid 👍🏼
Sounds like it's running super lean . More air also means more fuel is needed.
I was thinking the same thing. Seemed like the base idle screw needs some adjustment.
Or even a boost referenced fuel pressure regulator. Almost need an electronic fuel pump with a return setup to try and supply the fuel it needs id say
Absolutly way to lean, crank the needle valve up and maybe will work
@@castekracing thats why he went carb before supercharger. this way the carb doesnt see the pressure.
@@rehepeks that’s true. I haven’t done much with draw through.
I hardly ever give my full attention to TH-cam in general but your videos bring me to the table, I love how detailed you are with everything it’s amazing!
You haven’t bored me bro i am intrigued by your super charger and all the work that goes into your videos keep up the amazing work!!!
Adding a pressure bypass when throttle closes may help. Recirculating the pressure back to the intake of the supercharger, this would work best with the blow through design and relieve the compressor loading at idle.
This makes total sense, I just don't know how you can do it on something this small of a scale.
@@onefastslimjim true, but he manages a lot of stuff on a scale that is tiny, a challenge, just not impossible!
@@defaultdriftco00 oh yeah, knowing Johnny, he would find some sort of way!
Never bored with this content! I had a OS CZ .12 on my RC10 GT back in the day and it was all fun and games until the throttle stuck on my laneway and decided to end its life.
It's so nice to see new tools
You havn't bored me at all! Love this project. Love this channel. Looking forward to the next update!
Nice work! Still awes me every single time about your surgical like precision and steadiness!
I promise I wasn’t bored at all! This is extremely interesting content
A little tip with boost gauges that like to shake or flutter. Stuff a piece of clay with a wd40 straw (the tiny red ones) through the middle into the pipe used to feed to gauge. The gauge will be slightly laggy (unoticably) but a lot smoother and more accurate. I had to do it on my car's one 😆
They actually make filters for this. Also cotton balls work.
@@benjamindavidson632 yeah I saw the filters but they either seemed too cheap or too expensive 😆 had some milliput and a wd40 straw laying about so improvised 😆
@@MaNNeRz91 Yep RC filter, resistor and capacitor. The restriction is the resistor, and the pipe&gauage volume is a capacitor. Use to do this on boucing pressure transducers mounted too close to a pump set. Even just a length of plastic pipe with a crimp/bend in it works.
@@yeahright3348 i like how knowledge in electronics often can be applied to other fields tech
@@yeahright3348 I never thought about it as an electronic component before but that does make sense. Kind of like the bottle neck explanation for capacity and resistance. (I'm shit at electronics though.. I can repair stuff but I have no clue about working out current and amps)
totally not bored! this series is insane I love your work!
Love your engine build and tune series. That engine is a PITA to tune and one of the reasons why I went from nitro engines to 2 stroke petrol 1/5th scale rc.
You're ingenuity and ability to make things keeps it interesting.... Keep these videos coming.
Next stiffer valve springs and high duration/lift camshaft for 20000rpm. (and supercharger ofc) Maybe oil system upgrade. Soon the whole engine will be diy upgrades lol.
Great video keep them coming!
Yeah, I've really been wondering if the camshaft has much of any tuning ground into it at all. Not really familiar enough, but my immediate guess would be that (like the rough machined valves) it's only meant to be good enough to let the engine run as a "functional model".
check valve on the gauge should hopfully block it from reading vacuum
Not bored ive watched this 3x. Im just amazed at the skill you have building these tiny engines 👍
It's nice to see an "upgrade" is actually an upgrade and not another way to spend money. Thanks for showing the pre-lapped/post-lapped numbers.
That valve lift is pretty small, how close are the valves springs to binding? You might be able to make rockers with a more aggressive rocker ratio to gain more lift which will also help with higher rpm.
Would prolly get even more overlap. Which is what he is fighting right now I’m guessing.
@@henryarrington3446 overlap isn't always a bad thing in forced induction, especially in high revving engines. The duration of the overlap shouldn't change though, as without altering the cam profile, although the curtain area/time will be greater, the actual number of degrees per revolution that overlap exists will be the same. If boost drops it'll probably because the intake valves are exessively restrictive. Boost is a means to an end, if you reduce a restrictive valve you may drop boost, but if it means more air actually fills the cylinder then that's actually a beneficial drop.
@@17473039 your right I guess I worded it wrong. Overlap timing would be the same. But the valves would be open more during overlap. There is probably a lot of overlap in that engine to make it easy to start. I don’t know if it’s a flat tappet or roller lifters but if flat tappet you can’t get very aggressive on open and closing of valves. So builders have to put up with a little more overlap to get more duration/lift.
@@henryarrington3446 my guess is that being as cheap as it is, the cam probably acts directly on the rocker so it would act somewhere between the two. There is potential to advance the cam slightly so the intake valve close sooner so piston is closer to bdc when the intake valve closes, and rely on the supercharger flow and the overlap to help cylinder clearing on the exhaust stroke.
@@17473039 agreed bud. I think you and me are thinking the same thing is going on on the little engine. Johnny will get it sorted out I’m sure.
9 minutes in, hell am I excited to see Johnny's vids! :D
Amazing skill my dude! So many people can learn a LOT from you. More people need to take pride in their work like you do.
I like how clean and productive your work space is, Thank You for the awesome vids too
Would be cool to see if you could port the head.
I like a lot your videos for the things that you do, you’re one of the best TH-cam es I’ve ever seen
Don't quit you are just getting started! 3 tips, 1 I think a blow thru with a better carb is in order, 2 use a fluid filled gauge with a restriction in the line, and 3 make a large plenum on the manifold. If you look at what people have done for turbo's on small engines they need a "boost capacitor" basically it's a larger plenum for holding air to dampen the massive changes in pressure caused by low cylinder count.
JohnnyQ90, incredible work you do, always pure joy waching you bring thos engines to life ,,. 1/8th scale twin 4stroke, cant hardly wait,thank you!
You're not boring us at all :-)
when running boost you would have to advance or retard your timing ,I know that it doesn't have spark plugs but that would probably be the issue
Would valve float be a concern, I am not a mechanic just a hobbyist
@@LM-uz4pr valve float is an rpm related issue, the only issue you can run in to with changing camshaft timing is valve interference
@@LM-uz4pr Valve leak could actually be an issue that Johnny should inspect for. The valve springs weren't designed to hold positive intake pressure so the boost might be forcing air through them when they are supposed to be closed.
Hard to pull of but definitely cool idea
@@iNubAlert That's true for naturally aspirated cars. In the case of forced induction valve float can also occur when the valve springs are not stiff enough and the sheer air pressure generated by the supercharger/turbocharger manages to push the valves open
Love your work. Really looking forward to positive displacement supercharger too, will love to see how you solve that challenge.
Always enjoyable to watch the craftsmanship. thanks for the entertainment at work.
You need a gauge filled with oil to get a decent reading
I think some kind of restriction orfice also inline?
And a gauge with a stop on the 0 so it doesn't run backwards.
Restrictor should do the job.
I think the shaky gauge had more to do with there still being compression leaking into the intake. Same as if you've ever tried reading vacuum on an engine with a bent or overtightened intake valve. Could just be an RC engine issue ... I've never built a 16K rpm engine ... there could be all kinds of overlap on that cam for all I know.
could also be valve float like crazy..
Iv seen people do this on small motors like for go-carts you need to use a carb with a butterfly not a slide throttle. I dont know why but it just works
That is the coolest mini torque/screwdriver thing I've ever seen
Huge gain ! Never would have thought it would be that big of a difference .. ENJOYED..
It looks like your only tuning the high end needle? There’s a low end needle on the side of the carb as well. You need to tune the high end first to get peak rpm. Then the low end to get good idle and transition.
Also going over to electronic ignition and petrol/gas where it auto advances the timing might help 😊
What was going on there sounded a lot like a vacuum leak to me than a tuning issue. Or maybe some weird interaction between the carb and the supercharger causing an odd vacuum signal. Using an elbow between the carb and the supercharger might not have been the best plan. the more complicated the path between the carb and the engines vacuum the more wonky things get. I once ran what I thought was a pretty simple routing of a flexible (but very stiff) tube between the carb and the engine of my two stroke, and found the engine was virtually untunable. it always ran like trash. Then I eliminated the tube and mounted it as direct as possible, instantly found the right jet, and now it runs flawlessly. And yes I realize this is a 4 stroke of sorts, but these principals do still apply. A carb is a carb. (at least when it comes to 2 and 4 strokes-)
he's missing the pressure line on the lid of the tank. its starving for fuel, which is making it very difficult to tune.
I would love to see an rc car where the engine is in the front like a normal car, but its probably too much work
Great content as usual!
Id love the same. An rc car thats just a small copy of a real car
how about this? th-cam.com/video/PKVNOnmxJgc/w-d-xo.html&ab_channel=RCTanks%26Trucks24%2F7
@@rovoul1 ive seen it. Super cool.
It doesn't matter what you post. Your videos are hypnotic. Love your content. Do your thing.
You sure as hell haven't bored me. I love to see your work.
If polishing the valves worked that well on that engine do the same to your v4 to see if that gets more rpm also
I think you need to make an fuel injection system for it
A turbo would be easier to make than that.
@@sepg5084 your not wrong but you know he will find a way to make it
Never bored with anything you do Johnny I could watch this stuff allday everyday gr8 video bro....👌👌😉
Bored to death? no this is entertaining to watch and see the progress you make in making smol super chargers. keep up the good work
I like how you used flush cutters...
But didn’t cut them zippies flush 😂
*cries in mechanic* 😂
I think fuel is getting somewhere in your supercharger system, and tgan fuel gets clogged up at one place and than it gets realeased so it gets more fuel in different times. Thats why it doesnt run smoothly
The supercharger is clogged during idle then at wot it seems better, but after that supercharger can't stop drinking gas.
Dude nothing you do is boring! The stuff you do is insanely awesome! 👊😬👍
Looking forward to the roots blower, keep the awesome work 💪🏻
Maybe it needs stiffer valve springs.
what if the air that gets "comprimed" is to hot/big? make a tiny intercooler loop se if that helps?
The power increases slowy or no power increased, reason of the existence of Intercoolers doesn't matter its supercharger, turbo or centrifugal turbo.
In case of supercharged engines the cooling is down to the compressor before enters the engine, it's watercooled by a second radiator as intercooler, this also applies in centrifugal turbos used commonly in bikes.
I've been watching for this video. Valve lapping made impressive gains!
every video is just.. relaxing and interesting at the same time. Keep doing it
It's really strange how the engine behaves with the supercharger...maybe it has something to do with the blow through setup but I don't know
push a foam sponge into the sensor to make it stable
We never get bored, this content is too good!!
We are not bored keep it up and it will run like a dream
I've always heard draw-through setups are a bit problematic because in the case of unevaporated fuel in the intake (if you run the engine too rich), the droplets could damage the spinning compressor and with those high rotationnal speeds, damage the blades, Is that true?
With a prop/turbine spinning that fast I would assume that could be problematic at a certain RPM, how do jet planes turbines deal with rain?
It's true that draw through carbs are problematic, but it is because the centrifugal forces separate the fuel droplets from the charge air.
@@jakehartung3655 titanium blades
@@adamjacobs8606 titanium? That’s a lot of $$$
@@jakehartung3655 miniature engines are not airplane engines. The relative size of raindrops to an airplane turbine is miniscule compared to the fuel droplets on a miniature supercharger like this. Not to mention the materials used in airplane engines, the maintenance intervals involved in its operation, and the budgets of airline companies.
I... I can't wait to see this thing on a mini F1 chassis. The thing sounds like a mini F1 at 16k RPM
Put two of them together and you've got something a lot like a mini Cosworh DFV V8...
Absolutely not bored with this, I am willing it to work!
Amazing what simple polishing did. Didn’t know that could happen!
Not bored, more impressed if anything.
I want to see aluminium conecting rods for this engine
Super excited to see the new car run! Great Job!
Smallest things make the biggest difference. Great to know about that cheers mate.
im pretty sure the idle is weird because of supercharger surging
turbo surge is when it is trying to force air into the engine but the engine cannot accept any more air which causes the forced air thats being delivered to make its way back into the turbo's outlet and that is what makes that stustustu sound. theres no way the turbo is maxing out at idle. The idle is inconsistent because there are only two pistons so in between combustion cycles between the two cylinders there are no other pistons moving up and down to keep a steady delivery of air flow to keep the turbo spinning at a steady rate which at that point the whole cycle repeats itself.
watched this litte motor gain 4000 RPM by valve lapping and thought "wow" then i saw the super charger.
The motor has had that supercharger for a while now
Another brilliant video from a brilliant mind keep em coming Johnny
I'll never get bored of this stuff and I don't even know what you're doing most of the time
Johnny, my man, you think we are bored to death with this thing?
Boy are you wrong, there are 3 main reasons people watch these amazing videos of yours:
1-they are incredibly relaxing, 2-watching you make those parts and seeing how good of an engineer and craftsman you are is just incredible (btw, do you ever plan on uploading some videos where you teach us what you do to make these incredible machines of yours and how you do it?), and finally, 3-because watching these things work is, simply put, exciting.
What I mean to say is, there is no project of yours, made in your style, that could ever bore us.
Please continue this work..dont ever boring to see that ..
There is something extremely relaxing about your videos
Love watching you mess around! I want 1 for my living room
To be honest I'm not even "bored to death" with the supercharger. I think it's fascinating, and I would love to see more of it (even if it fails)
This is still very interesting doesn't matter if it doesn't work.
We aren't bored!
it sounds like it runs considerably better as well good work my g!
Keep up the awesome work!! So close to the Holy Grail so don't give up. Try finding an oil damped gauge cuz what is killing the gauge is needle oscillations ( it's moving way too fast). Years ago I ran across a book dealing with artificial boost for internal combustion engine design when I was playing around with turbo design for my bikes trying to eliminate most of the turbo lag. If you can find it, or something similar, that may help. Just keep at it cuz it is fascinating to watch you work. You have a talent that most don't. Can't wait to see you begin porting and stroking it (hint, hint).
I would happily watch more of this.
Duuuude that little torque tool is freaking sweet, didn't even know they made one like that. This guys shop must be a wet dream for hobbyists, I mean just his little 5 axis is 5 grand but his skill is on another level!
I would love to see the pro-charger work! Don't give up man!
Pure engineering skills that's why I'm studying it cause we can do stuff like this
I absolutely love this project! If it were me personally, I’d go back to blow through, keep your current pulley ratio to spin it fast enough, and run your fuel pressure tap from the intake tube between the blower and the carb. That way it should increase fuel pressure on a 1:1 ratio to boost pressure. You may also find that you need a stiffer valve spring. Even with such low boost, there’s still a good possibility that it’s blowing the valve off the seat and making it run erratic. Please don’t give up on it yet!
no, not bored with this build.... very impressive is the phrase...
to prevent the gauge from being damaged and giving erratic readings ..... us a long length of pipe between the manifold and the gauge.... at the manifold end place a restriction in the pipe, a bush with a 0.1mm hole in it, this will damp the response of the gauge and give the gauge a longer life span .. nice work... cool project
It should not be mechanical to begin with. Theres wayyyy too much fluctuation and its jamming it up. This will happen in any situation which is why ALLLLLLL boost gauges are digital.
You have NOT bored us sir!
Insane skills. Thanks Buddy
Awesome video, quick side note about the pressure gauges you were using. They made fluid-filled gauges that prevent the needle from jumping everywhere under fast changing conditions (and helps them not become stuck as a result) as with the slight resistance of the fluid, it makes the needle show the 'average' pressure compared to the 'instantaneous' pressure.
I'm was and will never being bored see your tests and research! Don't hesitate to continue
In this case due to exhaust smoke I could say the fuel is clearly not normally carrying to engine. The engine have it in excess when you open throttle and compressor puzch the "heavy" oil+fuel to engine.
If methanol is easy to transport on the air of your supercharger, oil that's take part of fuel could not be follow a such long tubing before engine
I think your problem is here.
Solution is hard but probably you need to separate air throttle and fuel
Install a fuel sprayer as near as possible to valve and a simple air carb where you want.
Though I am far from bored with the centrifugal supercharger, I'm beyond geeked to see you do some kind of positive displacement rig. I'm guessing you'll go with a Roots-style setup, but whatever it is, I know it's going to be dang cool. Good luck! Can't wait to see it!