[Will]

Agree with chiphead that stock rods that have NOT been rebuilt, checked, and had new bolts installed are a ticking time bomb waiting to go off.

Why someone would spend enough money to rebuild an engine and not at least have the rods magnafluxed, new ARP bolts installed, and resized is beyond me. Stock rods that are not badly out of shape when checked should be good to go for hard use after being rebuilt as above. If the journals are badly out of round or there is other evidence of hard use, I'd consider them suspect even if they pass mag inspection.

When you compare the price of a set of aftermarket forged rods (the cheaper ones available from some of the Pontiac vendors) vs. properly rebuilding stock rods, the price difference comes out to like $100. A drop in the bucket compared to the total price of the engine and the peace of mind they bring.

66geeto, you say the engine builder is much more familiar with Chevies than Pontiacs.... One VERY common mistake that chevy builders make is to install the rods backwards. On a Chevy engine the bearing tangs go on the outside, or oil pan rail side of the rod. On a Pontiac they should be installed to the inside of the engine. The rods have chamfers on one side of them and the bearing is slightly offset to one side to clear the radius at the edge of the crank journal. If he put the rods in like on a Chevy it's very likely the rod or a bearing seized on the crank.

I hope you can be there when the engine is torn down. Look carefully at the rods and note the position of the bearing tangs during disassembly.