Dumb question but i'll ask anyway

[MileHighDart]

Say you had a 318 with 9.0 :1 compression ratio

What kind of cylinder pressure numbers would you expect to see when doing a compression test on this engine?

 

[67Dart273]

Depends on cam, and cam timing.

For some idea of "factory" type cams, consult the shop manuals over the years. There is specs in there for compression "numbers"

 

[cosgig]

I believe a general rule for a used motor is that 125 would be great, 75 would be at the low side, anything g less and it's time to look inside!

 

[RustyRatRod]

No way can you connect compression ratio with cylinder pressure. The two are about as unrelated as 4th cousins 4 times removed.

It was a good question though, not a dumb one.

 

[diymirage]

Consistency between the cylinders is what you really looking for, less then 10 percent difference