Algodoo

You mean the right fuel pump thingies? I didn't think reversing it would be needed as adding more too much fuel only makes it slower.

And yes igottabomb's way worked just fine to stop the balls!


edit: I never knew you added a boost onto one of the gears!
Fixed it in new version!
(fuel pumps also needed reversing)

I'll try editing the spark plugs and see what happens.
Why do you suggest making the exhaust valves working? There is nothing to go out of the engine except for excess water.. And i'm not sure letting the excess water out will make it run better.

edit:
So all i gotta change is a - to a + in the rigth spark plug?
The left one already had "pos = [(e.pos(0) - 0.1), (e.pos(1) - 0.30000001)]"

The right one now has
"[(e.pos(0) + 0.1), (e.pos(1) - 0.30000001)]"

edit2:
Wow what did that change? It now runs much better, i peaked 1000000 joules with turbo!
I like how you can see the tank draining once you hit enter

Eat up more fuel? How?
Your design had the exhaust port closed. And if you open them the cylinder will only pump out 'unburned fuel'

Nice one, more energy than the four stroke version;)

Wow, awesome work.
It actually stalls etc..pretty impressive!