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nitro engine turbo

Old 12-25-2021, 03:08 PM
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adil23ciftci
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Default nitro engine turbo

I have a nitro engine and I want to turbo it. If anyone has done it before, can you please help? I have no idea where to find the turbo and other materials.
Old 12-25-2021, 06:32 PM
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Quit cross posting. It’s incredibly annoying.
Old 06-14-2022, 06:45 PM
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I have found that there is a company that makes superchargers for nitro. Turbo doesnít work well with 2 stroke. Some argue superchargers donít either but from my experience it worked very well. Very easy google search.
Old 06-14-2022, 08:41 PM
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You have it backwards I’m afraid.
Old 06-16-2022, 06:19 AM
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1967brutus
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Originally Posted by Jellis88 View Post
I have found that there is a company that makes superchargers for nitro. Turbo doesnít work well with 2 stroke. Some argue superchargers donít either but from my experience it worked very well. Very easy google search.
No ifs and buts: Superchargers do NOT work with ported 2-strokes. At all, period. You need a valved 2-stroke for that, and even then the effect is limited.
Sure, you can "hyperventilate" a twostroke, but then all you are doing is wasting a lot of fresh fuel straight into the exhaust, and the power increase only comes from less spent gasses remaining in the cylinder. That however, is not supercharging.
Turbochargers CAN work with both ported as well as valved 2-strokes. But turbochargers do not scale down very well, and in the size of our toy engines, zero chance that such will work: Simply because the power required to produce any significant boost at the volume flow required, is more than the energy availlable in the exhaust gasses.

It cannot be done in the sizes of engines as used in this hobby, and any vendor saying it can, is selling snake oil and hens teeth. Period!

Keep in mind: ANY engine manufacturer would immediately start producing turbochargers or superchargers if such a thing actually worked. ANY competition rider would use one if it would give him an edge over the competition.
Reality is: Only ONE manufacturer (and not exactly the silliest one at that, OS from japan) did, and built only a few hundred of those supercharged engines before they called it a day because the gains were not worthwhile. That was a 1,2 Cu.In fourstroke with a proper Rootes Blower on its back.
Old 06-16-2022, 07:13 AM
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I bought a supercharger system from rbinnovations years ago. They are still in business and still making parts. Even with an updated site. I had pretty good results with it. Using a tuned pipe helps a lot, alas I never used anything but a stock pipe that came with the car (not tunable) I was even able to start the car without a glow igniter from the increased compression. Have either of you guys saying it doesnít work tried anything from rbinnovations? Because if you look online 50% of people say these things donít work 50% say it does work. And everyone has their own theory on why it does and does not. As far as Iíve seen the only two stroke turbo to be used in full scale vehicles has been on a Detroit diesel, and the engine was built specifically for the turbo.
Old 06-16-2022, 02:59 PM
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I have an RB Innovations supercharger. It barely moves enough air to wiggle a whisker. They add (lame) bling, but they don’t work as they’re intended to. Charging can work on these engines, but it would be very minimal at best. These engines make more power by adding more fuel and oxygen to the combustion process, and by improving scavenging. Modified port timing, shape & size, and altering the fuel and glow plug have a better chance of making more power. Even there you won’t see a dramatic change. Make a change in the exhaust system and you’ll see a marked difference; namely in the manifold. Conical manifolds make much better power than cylindrical manifolds, and changing the length improves scavenging and power too. Knowing the port timings and adjusting the exhaust system to suit the timings will net more power. Pure and simple.
Old 06-16-2022, 03:40 PM
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I’ll also add - the RB Innovations snake oil supercharger only has one (loose) radial ball bearing. The fits are poor and loose, and it makes so much noise, I would worry about it blowing apart at 40,000rpm. I’ll sell it to anyone that wants to buy it though. Gullible is written on the ceiling after all.

RB Innovations is still in business because people are dumb enough to believe their hype and fall for it hook, line, and sinker. Those that know better don’t call for snake oil.

Last edited by 1QwkSport2.5r; 06-16-2022 at 03:44 PM.
Old 06-18-2022, 02:16 AM
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Originally Posted by Jellis88 View Post
Have either of you guys saying it doesn’t work tried anything from rbinnovations?
I don't have to... My entire professional education AND 30 years of work have been revolving around internal combustion engines and engine technology virtually exclusively turbocharged 2-strokes and fourstrokes, measuring and determining power, diagnosing and correcting issues. I can assure you, Detroit Diesel are FAR from the only ones building turbocharged 2-strokes. It is a fairly common principle, but it is totally useless in "on demand power generation", which is what your buggy engines are.
Superchargers (engine driven instead of exhaustgas driven) are another thing, but those are vitually without exception of the positive displacement types (Rootes blowers and the likes).
This thing is neither: it is an engine driven centrifugal fan. The worst compressor technology combined with the worst choice of powering it.

I know what works and what not, and I know how to distinguish actual improvements from "wishful thinking".

Don't get me wrong, I am convinced that you think you see that stuff work. Sounds change, noise changes, behaviour changes. But have you dino-ed it? Have you timed your laps? I think not.

Look... I have done a LOT of calculations on superchargers in my years. I know what kind of power they require, and what kind of RPM is needed to produce any meaningful boost. The physics simply are not there. radial or axial blowers simply do not scale down, because air itself does not scale down. Such a tiny blower wheel, it really CANNOT work unless it is spinning well over 200K, and that's where it is just beginning to work... somewhat.
The drive ratio's on those whimsical beltdrives are NOT going to provide the needed RPM, and those whimsy belts themselves are NOT going to transfer any kind of useful power.

Then: Radial compressors, IF they work, they generate a LOT of heat, because whichever way you turn it, the principle is inefficient in and of itself compared to any other form of pressurizing air. But even if they were efficient, compressing air by itself allready generates heat. There is very little point in boosting charge air without cooling it or you will lose half of the gains from compressing the air, to the reduction in density due to the temperature rise. A 100 F temperature rise is nothing when it comes to boosting charge air by means of a radial compressor. Where is the intercooler? Feed one of these engines air that is 100F above ambient, and it'll burn up from the resulting detonation alone. That does not happen (apparently, your engines stay whole) ergo there is no significant temperature rise, and that inevitably means, there IS NO boost.

There simply isn't... If there were, your engines would burn up. It is that simple.

Originally Posted by Jellis88 View Post
I was even able to start the car without a glow igniter from the increased compression.
This.... is not even POSSIBLE. Not going to say your engine did not start without glow igniter, because that is very possible and has happened to me numerous times even without such a supercharger contraption.
What I am saying is that this happening BECAUSE OF the supercharger is impossible. How can that charger increase compression when the engine is not even yet running to begin with?

EDIT, since I found this rather interesting: Take this, for example:Auxiliary Pressure System - Hydraulic Pressure Supply Systems – rbinnovations
This silly item is sold as an option. Think about this a little bit deeper.
In the set-up as designed by RBinnovations, the "boost pressure" is fed straight into the carburettor intake. Now, these carburettors, they depend on there being a vacuum in the carb intake, in order to draw fuel from the tank, right?
So, if there really would be any boost (boost=positive pressure) then the carb would not have any vacuum, therefore not any fuel draw. So this part, it should not be an option, but a necessity, IF there were any boost.
OK, OK, we could, with squinted eyes, reason that maybe the muffler pressure still is high enough to maintain a fuel feed to the engine. This means that whatever the case, muffler pressure is higher than boost pressure. It is not really important, but let's keep that in mind for the 2nd part of the whole story.

Now take a closer look at how this "option" is arranged. It's a simple pressure fitting and a Y-connector, so the idea is, that you hook up both boost pressure and muffler pressure to the "fuel cell" (fancy word for "tank").
What I am wondering is: have these guys never heard of Pascal's Law that says that a pressure in a single system spreads in all directions with the same force?
Two independent pressure sources hooked up to one Y-connector, their pressures do not add up. The highest of the two wins, and the highest pressure bleeds off into the lowest of the two until they equalize, which never happens because the "supply" lasts as long as the engine runs. That means effectively, since we allready have established that the supercharger on its own does not produce sufficient boost to disturb fuel draw, that chances are that muffler pressure is higher than boost pressure, and in that case, this "hydraulic pressure supply system" only bleeds of exhaust gasses into the air intake, and that is exactly where you do NOT want exhaust gas, because it displaces fresh air and fuel.

But it adds to the "complicated looks" (=bling) of the whole set-up, it is another 8 bucks in RB's pockets, and all they have to do in return is send you a few tidbits anyone can buy anywhere for maybe 2 bucks at best. I sometimes wish I could make my money like that, but OTOH, I would not be able to look in the mirror, or sleep at night.

Don't get me wrong, I am NOT out to slash you down. I am merely saying that what you see is one thing, but the explanations you have for it, are an entirely different thing and they are not based in any real physics. You spent a lot of dough on that supercharger, and you want it to work. I totally understand that. But reality is, it does not. Take it from someone that has a professional education in engine technology, supercharging technology and combustion technology on an engineering level.

Last edited by 1967brutus; 06-19-2022 at 12:45 AM.
Old 06-19-2022, 05:20 AM
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Providing the ports are timed and angled ideally, boosting crankcase pressure (trapped compression) will not increase the effective combustion compression ratio, but rather can improve scavenging because of the increased crankcase pressure. The true and only way to boost the compression ratio with forced induction would be timed pressure to the combustion chamber after the exhaust port is closed in a ported 2-stroke engine. In a valved 2-stroke, obviously the exhaust valve just needs to be closed. So to reiterate - supercharging or turbocharging a ported engine is pretty fruitless because boosting cylinder pressure isn’t possible. RB Innovations sells snake oil, and they know it. A lot of people are pretty dumb and buy their hype.
Old 06-20-2022, 04:53 AM
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Originally Posted by 1QwkSport2.5r View Post
So to reiterate - supercharging or turbocharging a ported engine is pretty fruitless because boosting cylinder pressure isnít possible.
Not to nitpick, but although supercharging is not possible in a ported 2-stroke, turbocharging IS... the turbine nozzle ring acts as an orifice and that makes it possible to boost a ported 2-stroke. I have worked with up to 25 psi boost in ported 2-strokes.
But it is basically only usable for engines with steady load and as little load variations as possible. It is totally unusable in any kind of "on demand" application.
In my line of work ported 2-strokes have gone the way of the dinosaur: about 30 years ago that I last worked on that one. That engine still exists, that ship currently is part of the US auxiliary fleet under the name USS Cape Knox and still has its original engine, but you won't find anything younger than that, I guess ...

Originally Posted by 1QwkSport2.5r View Post
RB Innovations sells snake oil, and they know it. A lot of people are pretty dumb and buy their hype.
That.... is totally true.

Old 06-20-2022, 08:57 AM
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Originally Posted by 1967brutus View Post
Not to nitpick, but although supercharging is not possible in a ported 2-stroke, turbocharging IS... the turbine nozzle ring acts as an orifice and that makes it possible to boost a ported 2-stroke. I have worked with up to 25 psi boost in ported 2-strokes.
But it is basically only usable for engines with steady load and as little load variations as possible. It is totally unusable in any kind of "on demand" application.
In my line of work ported 2-strokes have gone the way of the dinosaur: about 30 years ago that I last worked on that one. That engine still exists, that ship currently is part of the US auxiliary fleet under the name USS Cape Knox and still has its original engine, but you won't find anything younger than that, I guess ...



That.... is totally true.
The first part of my post you quoted was aimed at our model engines specifically despite missing that connotation. I know bigger engines can be turbocharged - snowmobiles and such have been successfully turbocharged. Thatís fact. Our little engines.... not so much for the reasons you already mentioned.
Old 06-20-2022, 11:06 AM
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Originally Posted by 1QwkSport2.5r View Post
The first part of my post you quoted was aimed at our model engines specifically despite missing that connotation. I know bigger engines can be turbocharged - snowmobiles and such have been successfully turbocharged. Thatís fact. Our little engines.... not so much for the reasons you already mentioned.
yup, this size cannot be turbocharged, AT ALL...
Old 06-20-2022, 12:19 PM
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Originally Posted by 1967brutus View Post
yup, this size cannot be turbocharged, AT ALL...
Yup. I think with some effort, the 4-strokes could. But not the 2-strokes.
Old 06-21-2022, 06:28 PM
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And crickets..... I figured we would have gotten the “you guys don’t know what you’re talking about. They work because RB Innovations says they do! Haven’t you seen their videos?” lines by now. LoL.

Old 06-22-2022, 02:12 AM
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Originally Posted by 1QwkSport2.5r View Post
Yup. I think with some effort, the 4-strokes could. But not the 2-strokes.
Turbo charging (the compressor being driven by an exhaust gas turbine) no way, the physics aren't in favour of that. Perhaps from 50 cc upward there MIGHT be a tiny gain to be had, but below? Very unlikely.

Supercharged, yes. OS did it, YS does it, but that is always with a form of positive displacement air pump. Never a fan be it axial or radial. Again, those damn physics...

JohnnyQ90 tried it with a shaft-driven radial fan, and utilizing the FULL power of the engine, there was some barely measurable boost. MIND: the only thing the engine drives in this vid, is the blower, which means ALL power of the engine goes to that fan. Nothing left to drive a model!
Mind you, that is 0,6 psi (something like 40 mBar, which is less than typical muffler pressure which usually exceeds 50 mBar), with a fan spinning 90K.. The RBinnovations fans spin about 30K if that, since their drive ratio is about 1:1 and the engine does not spin any faster. Especially not when lugged down by that useless piece of equipment attached to it.

Last edited by 1967brutus; 06-22-2022 at 03:39 AM.

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