Mercury Compression

[flyingfrizzle]

More even the better, A lot of the latter 2.5s should have 120-130 per cylinder and you want all of them with in 10%. The 1992 year compression could be a little lower than the latter years 2.5s but 110 is not bad if even. Seems like the 1991 year had a ton of changes or variances but the 1992 model should be more standard. Never the less if you are with in 5 psi of each hole I would be happy. A leak down test will give you a little better idea of what the bores look like but the 2.5s live forever if taken care of.