1966 327 / 1969 327 Harmonic balancer exchangeable?


I have a 1966 chevy 327 sb small journal and I need a new harmonic balancer, the local parts store has one for a 1969 327 small block, they look totally different but the hole for the shaft is the same. Can I use the 69 harmonic balancer?

Mr. Bowtie

John, The 350 Horsepower 327 had a different harmonic balancer, than the lower horsepower 327's. The high horsepower 327's had a 8 inch diameter balancer, the the lower horsepower 327's had a 7 inch diameter balancer.

The 1966 327 had a 2.30 inch main journal, The 1969 327 had a 2.45 inch main journal.

The 1969 crankshaft had bigger rod and main journals, which means the harmonic balancer was bigger in 1969 to balance more weight, compared to the 1966 balancer.

4 months ago

what is the correct GM part # for the harmonic balancer for a 327/300hp 1966 corvette?

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