Posted Bydustin dean on April 29, 2002 at 02:20:15:
In Reply to: Re: 1978 350 olds rocket posted byJIM on April 13, 2002 at 23:35:45:
: Olds 350's come in a few basic varieties:
: 1968 - 1972: Smaller combustion chambers, strong blocks, possibility of Nodular Iron cranks (a close second to the forged cranks that the 330's used). Four-speed 4-bbl engines had pretty decent camshafts. No EGR. Of course, if you get a W-31, you've got a pretty great engine right from the factory. The '68-'69 heads used a smaller exhaust valve than the later units. The high-compression pistons will make any of these a high-compression motor. 7/16" head bolts.
: 1973 - 1976: Larger combustion chambers, small intake and exhaust valves. EGR intakes, but the #8 heads were not too restrictive (compared to later units). Block is still relatively strong, with solid main webs. No more nodular iron crankshafts, but HEI ignitions on the later units are the best street setup. You need earlier heads to get high compression, even with high-compression pistons. 7/16" head bolts
: 1977 - 1980: Large combustion chambers, small ports, EGR, low compression. They did, however, have ½" head bolts (in common with the 403's and diesel 350's), though the windowed mains on the block make these the weakest engines to start a performance rebuild from. In reality, however, you're not likely to blow out the bottom end of this motor on the street below 6000 RPM
: YES PARTS ARE INTERCHANGABLE