I'm pretty sure I have blown up enough of them to know what is good for them or not these days

Not sure I agree with your first statement. my boat motors are quite literally car motors straight out of a chevy. No matter the motor, the principle of matching piston stroke time to a fuel burn rate still holds true.

from a reliable source:

Octane rating or octane number is a standard measure of the anti-knock properties (i.e. the performance) of a motor or aviation fuel. The higher the octane number, the more compression the fuel can withstand before detonating. In broad terms, fuels with a higher octane rating are used in high-compression engines that generally have higher performance.

Not sure how my post was wrong...please explain Adam.

Your math is correct but the key point your leaving out is cylinder head temps......driving around on the streets and not beating the crap out of it, you can run a NASCAR engine on pump gas.

All I'm saying is that there is a lot more than just simply your compression ratio when figuring what octane fuel you have to run

Answer this question: Why can you higher compression on the same octane by switching from iron to aluminum heads??? Jeff, feel free to answer because I think you prolly know...

Aluminum heads transfer heat better, which reduces cylinder pressure slightly.

Can we move on now? I dont think the OP really wanted to have this ongoing conversation...

Basically I choose to run 93 when available because it is a safer play.

I guess up here I will just drive a little more conservatively and use regular and change the tune up a little.

:coolcowboy:

Sorry guys....

I figured you guys wre bustin each others balls. :lolhit:

Boat is halfway here. :coolcowboy: