Two-stroke turbo!!

[sumaspikey]

I don't know if any of you guys have seen this, but after having a daydreaming session about engines (a regular occurence!!), i began to wonder whether it was possible to make a two-stroke turbo engine. I used to own a yamaha tzr125 when i was a teenager, and it always surprised me how much more power it had over a 125 four-stroke engine. Just imagine what it would be like with a turbo!! Anyways, i'm sure it'll entertain a few of u petrolheads out there!!


clicky

[Rs1]

You'll be wondering whether its possible to turbo a diesel next

[sumaspikey]

i take it this is old news to you then oh wise one?? i just wondered why i hadn't come accross it before.

[neil105]

didn't some american trains have suppercharged 2 stroke diesal engines in them

[Tathan]

at least your valves aren't gonna overheat an' fall off.

[Scoobler]

lmao shouldn't this be in the humour section - a turbo'd Vespa lmao lmao

[Gt5500]

A turbo charged two stroke lmao lmao lmao this has been raging on the model car forums for years. What you must remeber is that if you force air into a two stroke engine it will blow all the intake charge straight out the exhaust port. It can be done though Lotus have managed it they built a two stroke with fuel injection and a supercharger, not quite a turbo I know but it is forced industion and does make loads of power. To solve the exhaust problem they used a trapping valve to make sure the exhaust port was shut at the right time, it also had a sump like a 4 stroke. It will when fully developed be the most efficient thing since a very efficient thing.

[Gt5500]

On the subject of scooters you should see the nitrous'd Lambretta's they make make OMG do they shift.

[MartG]

20 years ago I did thousands of miles powered by a 2-stroke fuel injected turbo diesel - on a ship lmao

[CortraGTE]

lmao thats quite good

[Gt5500]

Yeah diesels on ships tend to be two stroke, and it works quitewelll because as we know diesels are all injected so you don't have the problem with the intake charge going out the exhaust.

[opelastra]

IIRC Peugeot was working on a turbo'd scooter a few years back called the Jetspeed or something like that. Remember seeing it on MotorsTV. Pretty sure that was a 125cc 2 stroke engine. Don't know if it ever went in to production though.

[opelastra]

I'll take back what I said, some digging shows it is a supercharged 4 stroke 125cc.

[sumaspikey]

well, i don't know about anyone else, but i would love to give this kind of thing a go if i had the mechanical knowledge and worskhop etc. I'm sure a few people have played with the idea, so there must be problems that have stopped it going into production. I know two stroke engines are more prone to wear, and are also less environmentally friendly due to having to burn excessive amounts of oil (in comparison to four strokes). So maybe that's why the idea would never take off.

[Gt5500]

No the idea never took off because as I said alreadyit doesn't work, a two stroke engine utilises scavenging to work efficiently. What this means is that as the piston comes down both the inlet and exhaust port are open, now this obviously means that the intake charge which is under pressure would be blown out of the exhaust port. Scavenging however works by backpressure from the exhaust, pulses of back pressure reach the exhaust port as the inlet port opens and holds the intake charge in. Now if you were to put the intake charge under even more pressure you would over come the back pressure and blow it out of the exhaust port not to mention the turbo would ruin the scavenging as it wouldn't produce the pulses. Another thing is that in a two stroke engine the crankcase acts like a pump so the carb venturi never has a direct route into the chamber so a turbo charger would also be very inefficient.

[sumaspikey]

say that again?

[sumaspikey]

i sort of see what your sayin tho. You really do know your stuff!! Might be getting myself a nice litlle KR1S motorbike for the summer....lots of two-stroke power.....but i shant be tryin to fit a turbo kit to it after what you have said!

[Gt5500]

I don't claim to be the expert but I do have a very good understanding of two strokes as I have been into Nitro model cars for a long time and also used to work part time servicing garden machinery. Not to mention the fact that this has been raging on the Rcuniverse forum for a long time now. A company called RB makes turbo's for model cars and they don't work but so many silly people belive all the marketing hype and have convinced them selves that they must work. Its a bit like all the people that believe all the K&N cr4p about filtercharging lmao and how it can add 15bhp to your engine, moral of the story don't believe any marketing hype unless you have some technical evidence to support it. By the way them Kwaka's sound good have you seen this site http://www.stanstephens.com/kr1.htm, they don't do turbo's but sound like they know what they are doing, although another thing I have researched extensively is Nikasil plating and these guys seem to like but it may be ok now our fuel is low sulphur