compression ratio and aluminum heads

[Custom 68]

Hey all, this may be too general but here it goes. I am running a set of 461 heads with 64 cc chambers on a 327 bored .06. I have flat top forged pistons. I figured I was around 9.5 compression Nothing (I believe) has been milled down. Does this sound about right? I have added tpi from an 86 it has been run on the chassis but not driven yet. I have a chance to get some 86 vette aluminum heads that are 58 cc chambers.
first does the guess comp ratio sound right?
will I be too high to go to the vette ones?
Is it worth the effort?
Currently I dont have access holes so I cant add a serpentine system but would like to?
Thanks
Dave
The cam is a computer friendly crane cam about 3 steps above stock but not the most aggressive they have.
again thanks

[Bobalouie]

Should be about 9.2:1, assuming a .025 deck height, with the 64cc heads and FT pistons w/ 6cc valve reliefs, and about 9.8:1 with the 58cc heads. Cut the deck down to 0 deck height, and you will get 9.7:1 w/ the 64's, and 10.4 w/ the 58's

[MrGoodpliers]

Hey Fletch, maybe you can answer this one for me... I've heard that you can generally run 1 compression point higher with aluminum heads. Why?

[64fleetside]

Aluminum transfers heat to coolant quicker, therefore higher compression can be used w/o detonation. Brian

[crazy longhorn]

10, or 10.5 to 1 will be fine with alum heads My 383 is at 9.8, with a fairly mild cam.....the shop that did the shortblock(Carshop, Moline Il), said just keep it under 11 to 1, if you cam it up, that will help. I run 90 octain fuel....6 intial on the timing., 32 total, + 20 degrees on the vac can (hooked to manifold vacumn). the curve is fairly fast for a "streeter", all in around 2600. at idle, she runs 26 degrees timing, & pulls 52 degrees under part throttle. That little sb dont spark rattle, & scares the chit out of this crazy old man (once in a while ). 4200 lbs of fun.....not quite hot enough for the strip, but too d@mn hot for the street! crazy L, havin fun

[neonlarry]

Also your TPI is good for another ¼ to ½ point. Besides the fact that you probably installed a knock sensor which will pull timing if you have any detonation.

[sam's 72]

I have those heads on my 383. This is how it is built. Block was deck to .005, 15cc dished pistons, quench is at .47, the heads were milled just enough to make sure they were squared up. I polished the chambers, which made them go from 58cc to 59 cc. The compression is around 10.0: to 10.3:1. I got these heads at a really really good deal. So I spent some money on them. I had bigger valves installed. and had them ported and polished. Gasket matched to intake and header. I just got my truck back on the road. The guy at the machine shop flowed the heads, I can not remember the numbers they flowed. but they are good enough to put out 450 hp. Have not had the time to tune it just yet. I have not got on it hard yet either. I did drop it into low gear at about 25 mph and nailed it and it just lit the tire up. I am haveing tranny troubles so next week it will go back to the tranny shop, and once I get it back, I am going to take the rearend out of it, shorten it, and put a posi with 4 56 gears in it. After that I will start the tuning on the 383.
Sam

[68c10owner]

my old 327 had kb 10.5 to 1 pistons( .100 dome) with 041 casting iron heads. i ran 16 degrees initial timing and 40 degrees total and it ran just fine on 91 pump gas. of coarse the custom ground schnider solid cam helped a little.