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I'm getting ready to rebuild my 400 in my 78 and I did a compression check today. I have a couple of questions ....
1. The first read I would get was 90 psi and it would take around 10 seconds to reach 140 psi. Is this a sign of bad rings? (because it takes so long to build compression)
2. Is 140 psi sound right for a 78 F-150 Stock 400?