Bought a cheapo Cloyes (stock replacement) that was too loose on a stock unrebuilt engine, just preventative maintenance in replacing the chain at 100k miles on a 318. Sent it back and got a quality set, Edelbrock in this case, fit nicely.

Might be the kit is loose, but since you've had a line bore or two done, might need a undersized chain. Anyone know how to measure and tell for sure?

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