Turbo Boost and FE

[GasSavers_Hal9000]

Originally Posted by mrjetskey

Being a mechanic and working on small engines in the 65 to 240 hp range,Watercraft.Higher compression will give better throttle response,a bit more acceleration and actually slightly less to speed on two identical engines.The only problem with this formula is it is two stroke engines I am talking about.

Same basic rules apply for 4 stroke engines. Higher C:R > higher output, better throttle response, (better FE as well), and better volumetric efficiency. The only real hitch is (like I mentioned in an earlier post) the human factor. It's much harder to resist using HP you have than HP that you don't have. That alone makes it hard to quantify the benefits of increasing C:R in my opinion and even if the engine is more efficient, if the driver doesn't have the restraint to continue driving conservatively, or doesn't realize that they're driving more aggressively (just as common in my experience), then any benefits will be lost and then some.