jjbadboy22

hi I am new at the whole rc world but I am into auto racing alot I want to do some mods to my engine which is a o.s. .18 but the mod that I want to do I have never seen on any rc car I want to build and install my own supercharger(forced induction) but what I dont know is if my little engine can handle the boost any info on this will help thanks

SqueedilySpooch

actully they have been made and most people belive they can't work on a two stroke such as urs.
People say it either would lean ur engine out too much with all the air coming in and others say its jus blown out the exhast when piston is down. However nobody can prove this with an real test because everyone thinks its not worth it without a clue of the outcome. So ur a risk taker with a big wallet shoot for it. If u have ur doubts on it don't do it jus get something else....

Micropuller

My Feedback: (1)

I'm in the process of building a "supercharged" r/c pulling tractor. The main reason for building the supercharger (it's a rotary vane style unit), is that I'm using two engines which I want to connect to each-other using a gearbox, thus making it a 2-cilinder. I want to make sure that each engine gets exactly the same amount of fuel/air, so they will run synchronized.

At first I won't be running an overdrive on the charger, because I also think that too much mixture will simply get blown out the exhaust port. I'd be happy if the engines would just get a 100% fresh charge each stoke. But maybe, if I get everything to work right, I'll change the gear-ratio to see if performance goes up. Theoretically, if the tuned pipes are working well, they should prevent the mixture from leaving the cylinder, so there's a chance it could work.

I know somebody who has built his own engines (14 cylinder and 7 cylinder radial, both two stroke) on which he used a rotary vane compressor to get the mixure to all the cylinders. These engines worked very well, without spitting fuel, so it should work.

I have some pictures of my first attempt on a rotary vane compressor here:
http://www.rcpics.net/view_single.php?medid=26729
http://www.rcpics.net/view_single.php?medid=26730

And this is the tractor I'm currently working at:
http://www.rcpics.net/view_single.php?medid=26113

Kmot

My Feedback: (24)

Micropuller! OMG, what a beast of a machine... it's wicked looking! Got any video of more machines like this?

PS: your rotary vane blower design is incredible!

Micropuller

My Feedback: (1)

Kmot, thanks for the kind words!

Some video's of these tractors can be found at:
http://home.hetnet.nl/~gijsen14/video1.mpg
http://home.hetnet.nl/~gijsen14/video2.mpg
http://home.hetnet.nl/~gijsen14/video3.mpg

This is our website:
http://www.micropulling.nl

For more pictures, go to "pullers" and select "vrije klasse", "super stock" and/or "two wheel drive"

Kmot

My Feedback: (24)

Thanks for the links! I wish I could hear the engines running!

I looked at your website and am stoked! I never knew such powerful machines had been built. It's all fantastic, thank you!

Kmot

My Feedback: (24)

Micropuller, I installed a supercharger on my 1/8 buggy. It seems to be doing something. I so far have opened my HSN 1/4 turn richer than before. It looks cool anyway!

Micropuller

My Feedback: (1)

That sure does look cool. And if you had to open up your HSN, that would mean that there should be extra air entering the engine. The question is, does that extra air and fuel get burned in the combustion chamber, or is it just blown out of the exhaust? Did you notice your car blowing out more smoke / liquid than usual?

I have almost finished the drivetrain for my new tractor. It includes a new compressor, which was designed way better than the one I posted earlier (I made that one just to see if it would do anything, which it did, but i never used it on a puller)

Pictures can be found here:

http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439
http://www.rcpics.net/view_single.ph...7ccf2f85495439

neil.jb

that is some truly awesome fabrication there, you must be very talented to produce something like that

Kmot

My Feedback: (24)

Wow! Awesome micro machining!! You must be a journeyman machinist by trade?

supadan

i cant vew the pic man can u not put them under rc pics

redheat8

Your little system looks nice but I would be willing to bet that by adding a motor saver filter and a long snorkle tube you could get the same motor results, now I'm not taking anything away from your theory of air blasting into a carb. giving the motor a leaner air /fuel mixture and producing more power , It just seems more practicle to go the other way, RED

Micropuller

My Feedback: (1)

Actually, I'm not, nor did i recieve any education on operating a lathe or a mill. I just bought a bench-top lathe a couple of years ago and started experimenting

@ supadan: I heard people having this problem often with RCpics. Most of the time it has something to do with your firewall settings.

@ redheat: your partially right. It's possible to tune an engine's intake, just like you would tune the exhaust. it's a bit more complicated than adding a piece of tube and a good airfilter though. It's way easier to have some kind of mechanical device push the air into the engine. The main question is, will all this extra air / fuel be burned, or will it just get blown out of the exhaust? I'll know the answer to that question when I'll fire up the engines for the first time

redheat8

Micro now well your system be a constant flow of air or as the RPM climb well the air flow increase? Now I'm thinking that the air flow well increase as the motor RPM increase which would cause me to believe that the fuel mixture would become very lean very fast, RED

Micropuller

My Feedback: (1)

redheat,

Yes, the airflow increases as the engine RPM increases (the compressor is linked to the engines using steel gears)
BUT, as the airflow increases, the amount of fuel will also increase. That's why the carburettors are mounted on top of the compressor and not the other way around, like the one used by Kmot or those produced by R&B innovations.

The inlet-air is sucked into the compressor through the carburettors and the fuel is added to it before the air enters the compressor (just like it would if the carburettor was mounted on the engine directly) So, the air / fuel relationship in the mixture will stay constant as RPM increases. This method has several advantages:
- The oil in the fuel lubricates the compressor, just like it does an engine
- The fuel / air mixture is compressed, which, as a side effect, creates heat. I expect this heat to cause the fuel to evaporate, thus creating a better mixture to be fed to the engines.
- On the other hand, the evaporating methanol will actually cool down the hot/warm mixture before it enters the engines, which in turn means more mixture will be able to enter the engines. (as you probably know, cold air takes up less volume as compared to hot air)

redheat8

In principal it all sounds good but I'm still not so sure about the practicality of it, whats to gain from it, I mean as far as HP.,and would it be dependable, I notice a couple of wires coming out of it can you explain what they are for? RED

Micropuller

My Feedback: (1)

As I said earlier, we'll have to wait and see:
But there's one thing I'm absolutely convinced of; if the only thing the compressor does is make sure that the engines get a 100% fresh charge every stroke, that alone would mean an increase in engine performance. If this means that the excess is blown out of the exhaust, that's fine by me. I'm into pulling and thus mainly interested in making maximum horsepower, not good mileage.

Just curious, may I ask what experience you have in supercharging combustion engines? are you an engine modifier?

redheat8

Engine modifing only as far as polishing ports and carb. tuning ,thats why I find your project very interesting, I havent had great success in port work but I do pride myself on mix matching and tuning carbs.keep me posted on the progress of your test motor, RED

Kmot

My Feedback: (24)

Even more impressive, then!

You might be interested in this treatise, Micropuller:

http://naca.larc.nasa.gov/reports/1939/naca-tm-908/

supadan

nup rc pics still dont work it is jsut gay

killer89

My Feedback: (-1)

superchargers will work on 4 strokes only...

p113

amzing cars but how are the engines linked up as in the 2 side by side

JRexA

You can get plenty of 2 stroke Turbocharged Engines, but OK

A 14 cyl 100000 HP MAN B&W 2 stroke Diesel might be overkill in an R/C Car.....

Plenty of the larger Marine Diesel engines are two stroke and turbocharged.

Happy driving from Greenland
Jesper Rex

dalolyn

My Feedback: (7)

Supercharged and turbocharged are two deferent things. supercharging utilizes a mechanical device to turn the vanes be it a electric motor or off of the crank. Superchargers are devices using a rotating impeller to accelerate the incoming air to high velocity which is then converted into pressure as the air slows down in the surrounding diffuser. turbo charging uses the exhaust pressure and heat to create boost. A turbocharger is simply a centrifugal compressor driven by exhaust gams. It consists of two rotors connected by a common shaft. One rotor, called a turbine, is located in the exhaust stream. The other compressor rotor is placed on the engine's intake system.

Frost_

My Feedback: (1)

You missed the point by 180 degrees.....

We aren't talking about production diesels with VALVES....

Tell me how you can build positive pressure in the cylinder (greater than 1) when the LAST PORT TO CLOSE IS THE EXHAUST... any pressuization you add through the intake and boost port are lost to an open exhaust port, get it?

The ones similar to what is shown above on the buggy make MARGINAL differences, less than .1 HP at the top of the RPM band (if I could find the dyno article test on this I'd link it...) so they make SOME more power, but NOTHING LIKE the 30-60% increases that can be realized on a REAL eninge with VALVES...