harmonic balancer 64 Corvette

[Bob Gibson]

Is the a difference between the low horsepower and highpower? If so shat is the difference.

[Joe L.]

Re: harmonic balancer 64 Corvette

Bob---


Yes, there is a difference. The 250 and 300 hp engines use balancer #3896904. This balancer is, I believe, about 6-3/4" in diameter and about an 1-1/8" thick. The 365 and 375 hp engines use balancer GM #3817173. This balancer is 8" in diameter and about 1-11/16" thick. Original versions had "fin-like" reinforcing ribs on the rear side of the balancer inner hub. These were NOT cooling fins as many folks think, but simply a form of hub reinforcement. Current GM service parts do not have the reinforcing ribs. Both of the above-referenced balancers are still available from GM.

[Gavin Norman]

Re: harmonic balancer 64 Corvette

Just to add my experience with the two balancers. The SHP finned balancer with its added bulk is significantly heavier and can be pressed on with the bolt that secures it to the crankshaft. If you are looking for one - they aren't cheap! I was keeping my eye on used balancers for about 5 years at the shows but wasn't willing to spend $300. I finally found a good one for $200. There is a guy that manufactures them now (i.e. with the fins)and he wants $300.