1963 Hi Perf Crankshaft

[Ron Hambrecht]

I have a 63 Coupe with a 360 hp F.I. engine. I found the correct "finned type" balancer to replace an incorrect non finned. The hi perf "finned" balancer was loose on the outer crank. When I contacted the supplier he said I probably didn't have the "high performance crank shaft" that came on the 340 hp and 360 hp engines.

Does anyone know if the 340hp & 360 hp actually had a different crankshaft ?

[Clem Z.]

Re: 1963 Hi Perf Crankshaft

all small block crank snouts should be the same diameter,hi per or not

[Joe L.]

Re: 1963 Hi Perf Crankshaft

Ron-----

The primary difference bewteen the 1963 250/300 hp crankshafts and the 340/360 hp was that the 340/360 had the snout drilled and tapped for a balancer retaining bolt. The 250/300 hp cranks did not. For 1963, ALL 327 Corvette cranks were forged steel, although several different forgings may have been used.

[Mike M.]

Re: 1963 Hi Perf Crankshaft

O.D. of snout of crank is identical in the 250/300 hp and the 340/360 hp engines. as joe stated, the snouts are drilled and tapped for balancer retaining bolt and washer. Aslo believe the 340 and 360, hp were heat or chemically treated(?tuffride?) of some such trademarked hardening process but bottom line is all snout O.D.'s the same . seller pulling your leg. mike