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Old 09-05-2012, 08:09 AM
Mr. P-Body Mr. P-Body is offline
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It cannot be emphasized enough: REPLACE THE CONNECTING RODS. Not just the bearings. The cast rods were junk the day they were made, and that was over 40 years ago. For $279, don't "cheap out" on the most important change you can make to the Pontiac. Don't let a shop convince you they'll (cast rods) be "alright". They (shops) make more money rebuilding stock rods with new bolts, than selling GOOD rods. At $20 each for resizing, and $65 for new bolts, you're just about at the same expense as new rods. Be smart.

Cranking compression in the high 160s-low 180s indicates it probably still has flat-top pistons in it, and an original type (if not the "real deal") cam. The solution is to turn a "dish" in the top of the piston about 12-14 CCs. Since you're going to have the pistons off the rods anyway, a good time for that. Rebalance woiuld be called for.

DO NOT install new lifters on a "used" camshaft. It WILL fail. While it used to be a fairly common practice in repair shops, we don't do it anymore due to the changes in oils and metalurgy. Good time to install a new, more modern cam grind, though! We use Comp XE grinds in virtually everything today. Remember, this is NOT a "Chevy", and reacts to input differently than the Chevy. What this means is, pay little heed to complaints about Comp. Leading edge and VERY good. Their solid rollers for street are the s**t... (:-

Jim
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