Thread: 396 375hp build question

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The 375 HP 396 was the L-78 motor, with mechanical-lifter cam, large-port iron heads, 11:1 compression ration, 4-bolt mains, forged Tuftrided crank and forged pistons. 11:1 on the street today is a problem because of detonation.

The cam timing was 40-86/88-38 (306/306 duration at 0 lift), with .500/.500 lift. (Casting #3863143)

You've got the same block used in the L-78, but not the heads. The heads you have were used on the 396/275 HP LS-3 engine, have a larger combustion chamber and smaller valves.

Here's a link to a page with the full L-78 and LS-3 specs.
http://www.nastyz28.com/camaro/z27396.html

Cam grinders make reproductions of the cam, but there are probably better grinds out there for what you have.

I can tell you what you have, and what the L-78 had, but there are other folks who can tell you how to build a strong engine with your parts. Erik Erikson or Pat McCarthy.

Myself, I'd be wary of duplicating an engine for the street with solid lifters and an 11:1 compression ratio. You can get massive HP out of a BBC without going that direction. Get down around 9 to 9.5:1 with your heads and pick a good hydraulic cam, and you can get your 375 hp easily.

Thanks guys, I saw on a different site earlier tonight the info on the solid cam setup for those critters, no thanks. Your right, a good hydraulic cam around .500 or so and something domed to get me 9.5 to 10.0 should get me in the ball park (I'M TALKING YANKEE STADIUM HERE). If I'm barkin up the wrong tree, let me know. I like the 2.19 idea, if it wont kill my bottom end.