First off....what does everyone think are GOOD compression #s for an SR20....I searched but couldn't find any "standard" numbers.

It seems like 150-170 is good, but I wan't some more input.

Also, can anyone explain to me where these numbers come from?

At first, I figured you could mutiply atmospheric pressure by the compression ratio, but I know that isn't the case. Do you add the amount of boost to the atmospheric pressure and mutliply by the compression ratio? Or is there no formula for actually calculating it?

Thanks


***Mods...I posted in Engine Swaps, but wasn't getting an answer or a significant number of views, so I am trying here.

 

bump

I can't believe there isn't at least somebody that knows this....I've searched everywhere but can't get an answer

 

i cant explain any of it lol but ive heard the same numbers you have

 

nobody has a sr20 fsm?

 

I think around 165 is what is in the FSM, I don't have it on my laptop so I'd have to check for sure later. You can download the FSM too and check, theres a thread in the FAQ section with a download link.

 

thank you very much