The cam bearings and the main bearings have the greatest impact on oil pressure, in that order. If the engine is torn down to the block, go ahead and change the cam bearings. Cam bearings, correctly sized mains and a new oil pump will bring the pressure back to between 30-45 PSI where it should be. Don't forget the rod bearings while your at it. Its best to have the crank turned .010" undersize and new bearings fitted since you're in there.

The .0015"-.003" is correct clearance for main and rod bearings on 55-62 235 engines. .002" is optimal. Check your manual, but I think main bearings are torqued to 90-95 ft-lbs, rods are 40-45 ft-lbs or so. Somebody else will clarify Im sure.

good luck

chip

Preaching the Hot Rod Gospel according to the 4-stroke apostles:

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