What should my compression be

[Mike Moore]

Did a search on here and can't find what my compression should be on my EA82 carb motor. can't find it either in my book. Did a valve job and it's worse now.

[TomRhere]

Look more for uniformity than a set number. But 110-120 would be a good range, some have reported more. Can't remember right now what mine where when I did a test on it.

 

If one side is way lower than the other, chances are you have the T-belt off a tooth or two for that side.

[Phizinza]

Any lower then 110 and I think you will be wanting a rebuild/new engine.. A freshly rebuilt EA81 (near sea level) gets about 140. And EA82's only run a little less compression (I think) so 130 should be nice.

[Uberoo]

what is the compression ratio if the heads were milled .011"?The heads for my brat had to be milled eleven thousands to be flat.they must have been really warped.

[GeneralDisorder]

It really all depends - I pulled 220 on every cylinder from my EA81 hydro lifter block. Fairly low mileage from an automatic. No rebuild or anything. My EA81 in my Brat with 175k on it pulls 150 in every cylinder. Both run equally well.

 

As was said - it's not the numbers, it's how even they are.

 

Anything lower than 90 should be investigated - possibly a partially blown HG, or something. Subaru engines do not really get burnt valves, and do not wear the cylinder bores - and it would take a TON of miles to wear out a set of rings (well over 300k).

 

GD