getting ready to rebuild 350 for 69 cutlass. I've driven it for years and its been on my list (leaking oil/smokes a bit) I dont think its original block but it is 588.casting. Looking to do stock rebuild with maybe mild cam upgrade. this is street car with power brakes and original A/C car (though it is not installed yet). I've rebuilt a few pontiacs and BBC over years. Basically asking for advice for oldsmobile shops for parts/cam advice (or who to avoid). possibility of using stock rockers with larger cam or need to upgrade to adjustable? any upgraded parts/gaskets that have come out over years to make build more dependable/fewer leaks? Like I said, this is going to be daily driver - no headers (are there better flowing factory exhaust manifolds available - similar to pontiac having repro ram hair manifolds available)?
thanks
Eric

 

588 would be a rear differential casting number. Do you mean a 395558 engine block casting ? Cutlassefi could help you with cam & valve lifters.

 

All that block casting number tells you is it's a 1968-1976 engine block. Check the head near the #1 spark plug for the casting letter:
5 = 1968-1968
6 = 1970
7 = 1971
7A = 1972
8 = 1973-1976

All of the above heads are nearly identical with the exception of 8 heads, which have HUGE combustion chambers and therefore will give much lower compression ratio than any of the others.

Speaking of compression ratio, you need to be careful with piston selection as some of the readily available "stock replacement" pistons have large dishes and will result in very low compression ratio.

You should be able to use the factory rocker setup with your new camshaft as the W engines with .474" lift used them from the factory. The one thing to keep in mind is a new cam may have a different diameter base circle and need slightly longer push rods. You should always measure to determine the length push rod needed after a rebuild anyway as machine work to the heads/block and aftermarket head gasket thicknesses can impact the length needed for correct valve train geometry.

 

Do a compression test before pulling it apart, you may be surprised or at a minimum end up with information on what to look for while it is apart.

Is the current engine a high compression version? Are you planning on boring/new pistons? If yes, be careful as Fun71 mentioned with compression ratio/piston selection. Other members can guide you on that but don't just accept a rebuilders piston without knowing exactly what it is.