Bought 98 Bonneville with 163k and typical old GM oil pressure gauge dance. Replaced sending unit and changed oil with 10w40 DEFY and a PL10111. Now I get 40psi cold start pressure, and 20+ warm, but it doesn't seem to want to go much higher than that, ever, almost like the relief pressure is set at 40psi. Is this normal? I've never had one of these big iron block engines before.
Before its asked, the upper plenum looks sorta fresh and the intake gaskets appear to be leaking a bit externally, for now it will get some bars leak. I'll deal with it correctly in the spring with a new plenum, the good fel pro LIM gaskets and aluminum elbows.
Before its asked, the upper plenum looks sorta fresh and the intake gaskets appear to be leaking a bit externally, for now it will get some bars leak. I'll deal with it correctly in the spring with a new plenum, the good fel pro LIM gaskets and aluminum elbows.
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