Thread: 327 Build Cam Selection

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Originally Posted by H.O.Rider

Car is built to look like an L79 Nova that's why I didn't chose an LS or a big block. I'm building an LS for my CJ7 presently.

My cam choice at present is a Hydraulic Roller from Howards

278/278 225/225 .525"/.525" lift with 1.5 rockers or .560" lift with 1.6 ground on a 110 LSA or possibly 108

That's a BIG cam for a 327, it'll be pretty rumpity! Reminds me of my '62 vette back in the days, lol! Light weight car, good gearing, 4 speed, it'll be fun!

With 10.3:1 compression ratio, you will want to be careful about your dynamic compression ratio so you don't have a problem with detonation on pump gas. Use one of the DCR calculators like Wallace Racing: Dynamic Compression Ratio Calculator to plug in specs. Intake valve closing at ATDC is critical. For instance, my 383 has 10.6:1 static compression, and I originally was thinking about running a particular CompCam XE-274 but with its ATDC at 64 degrees, it put my DCR over 8.5 which is a no-no with pump gas. So I chose their Magnum 280 which had similar specs. It has a ATDC at 66 degrees which gave me a DCR of 8.46 which is acceptable for aluminum heads and 92 octane. I hope this helps.

Originally Posted by 36 sedan

That's a BIG cam for a 327, it'll be pretty rumpity! Reminds me of my '62 vette back in the days, lol! Light weight car, good gearing, 4 speed, it'll be fun!

I'm running a 327 right now with similar compression, except for double hump iron heads, with a Comp Magnum 280 cam. Its got a nice lopey idle. Not too big of a cam, makes about 10-11 inches of vacuum at 700 RPM if I recall

Originally Posted by rumrumm

With 10.3:1 compression ratio, you will want to be careful about your dynamic compression ratio so you don't have a problem with detonation on pump gas. Use one of the DCR calculators like Wallace Racing: Dynamic Compression Ratio Calculator to plug in specs. Intake valve closing at ATDC is critical. For instance, my 383 has 10.6:1 static compression, and I originally was thinking about running a particular CompCam XE-274 but with its ATDC at 64 degrees, it put my DCR over 8.5 which is a no-no with pump gas. So I chose their Magnum 280 which had similar specs. It has a ATDC at 66 degrees which gave me a DCR of 8.46 which is acceptable for aluminum heads and 92 octane. I hope this helps.

Absolutely will do. the 278 cam on 110 makes very close to 8.5 DCR on my application