How much does compression influence the "power" or toque output of an engine? I'm not taking about compression ratio of the piston but instead what you measure with a gauge when the engine is cold.
The stock AVL 500 engine has a cold compression of 145 - 150 psi. I personally have run compressions of up to 175-180 psi with good success ( ie no pinging, but with lots of other mods). Just wondering how much of the performance gain is due to the increase in compression and how much the rest of mods.
Just out of curiosity, say we have two identical engines: one running at a lowly 145 psi and the other at max compression possible without it knocking , say around 175 psi. Would the performance be dramatically different?
Let's also suppose that we have the best bottom end installed so that's not an issue.
One thing I did notice is that the oil turns black very fast, even with a proper run in barrel and piston. This is obviously due to blow by, yes? That can't be good for the engine breather system, can it? Having to work more? Is there anyway to gauge what's the highest usable compression to achieve optimum power with out the ill effects of blow by etc?