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Discussion Starter #1
I've heard it said that with the addition of a longer duration cam, (such as a hotcam or ZZ409 etc), that this will allow for a higher compression ratio.

My LT1 has 10.4 CR now and a ZZ409 cam. Is there any reason why I couldn't have the heads milled to say 10.8 or 11.0 CR and still be able to run in 92 octane pump gas, AND get a few extra ponies out of the deal besides?

The heads have already been fitted with LT4 sized valves.
 

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theres several factors at work, but in general youll want to stay under about 8.2:1 dynamic compression, with aluminum heads and 92 octane gas, here read this first

http://www.digitalcorvettes.com/forums/showthread.php?s=&threadid=5963

heres the cam info
ZZ-409 Hyd Roller:

Adv. duration 287/287, duration @.050 226/226, Lift .520/.520. 112 LSA.

a quick check shows 10.8:1 SHOULD be fine but 11:1 gets close to the limits where detonation MIGHT be a problem, keep in mind that a full point in compression is worth about 3.5% in power so if you boost the compression from 10.4 to 10.8 and your currently making 350hp you can expect the compression increase to boost hp by about 4.9 hp, thats hardly worth the effort
 

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Remember that if you mill the heads, you will havre to mill the intake to match the ports otherwise the small gaim in CR would be offset by the mis-matched intake ports. S lot of work to get it right. If you want more compression you might consider different pistons ot heads, but that can get expensive real quick
 

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Discussion Starter #4
Between your comments and Grumpys info, you've talked me out of it. I really had no idea it was that involved.

It's a good thing I asked first, haha.

Thanks
 
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