What is the max safe timing i can use on a 7.4l with the gm performance aluminum heads,10:1 compression wich i think the heads bump up to 10.7:1, and the zz502/502 cam. running 93 octane.

heads are
combustion chamber 110cc
runners are oval 290cc

cam specs are
224*/234*
.527/.544 at 110 lsa

Thansks.

34 total advance, I wouldn't any higher than 36.

36

unless you have modified your pistons or deck height you're not at 10:1 and definatly not 10.7:1 on a 454.

with a 110cc combustion chamber and a stock pistion that still sits .020 in the hole you're around 9.5:1.

In any case 36 is still where you wanna be.

DAVE

Im running the srp 10:1 dome pistons.

Is there a way to check what my compression really is?

32 degrees is safe. 34 is ok as well , but with all the ethanol in the fuel these days,,,, .

You never know where you might be and need gas and all you can get is crap, I like the 34 mark myself. Especially if your not an all out need every ounce of HP you can get kinda guy.

John

Ah! Now it makes sense. As far as calculationg CR your piston card should have the amount of cc's it is at TDC. In your case it may be a negative number.
your head gasket will say the same on the package. If you're using a fel pro 1037 I believe thats a 10.9 cc and lastly you already know your head is a 110.
So with a piston volume of:
-20cc = 10.7:1 @ 96cc total
-15cc = 10.2 @101
-10 = 9.8 @ 106

Just to give you some rounded figures
DAVE

I have no idea...but my builder wanted it at 32 so there would be no problems!!!!!!

thanks ill look for that info.