1965 396 hp ratings !

[Joe L.]

Re: i am sure the exhaust manifolds made some

Dick-----

The heads used for the 1965 Corvette L-78 were not unique to that application; they were also used for the 1965 passenger car L-78 and the 1965 Chevelle Z-16. The Chevelle engine, which was rated at 375 hp, did use an hydraulic lifter cam, though.

For 1966-69 Chevelles and Camaros with L-78 engines, the heads were, indeed, of a different casting number than those used for the 1965 L-78. However, they were functionally identical in all respects---same combustion chamber configuration, same combustion chamber size, same rectangular intake port configuration, and same valve size as 1965 Corvette L-78.

The 1966-69 L-78 engine used in Chevelles and Camaros used the same camshaft as 1965 Corvette L-78. However, those used for 1967-69 had a different part number since the rear cam journal groove was eliminated for 1967 and later engines. So, this feature of the cams changed and, consequently, the part number changed for this reason ONLY.

[Clem Z.]

joe did the big body cars use the light weight

nodular iron flywheel the like 65 396 corvette engine????

[Joe L.]

Re: joe did the big body cars use the light weight

clem-----

No, they did not. They used a standard weight, 14" flywheel and 11" clutch. The Corvette L-78 was coded "IF" whereas the passenger L-78 was coded "IE".

[Dick S.]

What else was different?

At what point did GM change the engine designation? Were all 396's in 65 L-78 regardless of configuration? So far we have a cam change from solid to hydraulic, different exhaust manifolds, carburetor, flywheel, distributor. How about the intake? Did the Chevelle have the high rise aluminum intake? If so, how did it clear the hood?
I would have expected that the cam change to hydraulic alone would have warranted an engine designation change.

[Mark #28455]

Chevelle engine had different assembly stamp

The Chevelle engines started with an "E" (like EF) instead of the "I" for pass engines, so as far as Tonawanda was concerned, they were different engines, so a change in cams or other parts was no big deal. The high rise intakes fit perfectly in the Chevelle - even the cast iron intakes were of the high rise design through 1969 in pass cars (Corvette changed to lo rise for 1968).

Mark

[Joe L.]

Re: What else was different?

Dick-----

Not all 1965 396 cid engines were L-78. Passenger cars had a 325 hp 396; it was designated L-35. I don't know what the designation was for the 1965 Chevelle 396. It was rated at 375 hp but it was installed only as part of the Z-16 performance package. Much like the Z-28 Camaro and the ZL-1 Corvette which were, technically, a "performance package", the engines had no separate engine designator (i.e. L-xx) that I am aware of. If they did have such a designation, it was an internal-to-GM sort of thing.

The 1965 Z-16 Chevelle was a very limited production thing. Only about 200 were ever made.

All 1966-69 Chevelle and Camaro L-78's used a high rise manifold very similar to the 1965 Corvette and Passenger car L-78 manifold. 1970 L-78 in Chevelles and Camaros used a "pancake" manifold; the same as 1971 Corvette LS-6. The 1966-70 Chevelle and Camaro L-78 was a solid lifter engine just like the 1965 Corvette and passenger car L-78.