So is this right????? this makes sense to me now.



When u compress the air in the turbo it gets cool by an intercooler.

When u comrpess the air in the engine, there is nothing to cool it.

Compressing air heats it up.

Therefore when u run a lot of boost into a high compression motor the air will be getting a lot hotter, and detonation( the igniting of the mixture before the spark plugs) will be more likely to occur.

 

um i think sorta, but in the chamber the mixture needs to be at a certain temp to help it light off?



mike

 

Well, maybe in a diesel engine. But in a spark-ignited engine, the mixture can be pretty cold indeed and still light off. Well-atomized fuel helps in this respect, better yet fuel that is completely dissolved in the air.

 

rotary engines seem to need to be at around 78-92' C to run right, mine seems to be happiest at around 85-88' C.... I think the temp helps with the fuel atomization.. Part of this is the very short period of time between air entering the combustion chamber and ignition/compression and the fact that the combustion chamber is moving.. Not a whole lot of time to get a good mix on.. Piston engines tend to make better power at slightly lower temps, but they have more time for the fuel to atomize and they also have a better squish area that's not moving so the burn can be controlled.. That is also why a piston engine needs a lot less fuel to make the same power as a rotary engine and why we get shitty gas milage..