My heads have been milled (probably 3 times before I got them) They were ported by MTI, and I was told they were worked some more buy another shop. I had the heads milled for straightness and had my machinist cc the heads and he told me that they cc'd 48. Is this possible?

 

That sounds like a lot of milling.
Do you know how much was taken off each time?

The CR would be insane with stock pistons
https://www.camaroz28.com/calcs/cr.html

 

With my new motor I figured it to be 12.9. I'm going to have to do something, maybe a much thicker head gasket.? I don't know.

 

I'd kinda be worried about piston to valve clearance!?

-Dustin-

 

These heads came off os XXsaint69x's 383 that only made 12.1 compression. I don't have a whole lot of info as I bought them from a guy that never used them.

 

You will want to pay attention to P/V clearance and also try to find a compromise for quench height if possible.

Happy 4th
Steve

 

they were not 48cc when they were on my car, i believe they were 52cc or something around that, i also believe my headgasket was around .060.
Marcin

 

To go from 52 to 48cc you would need to deck them about .025" - That would take some serious warping of the deck to require that much removal...usually I will cut .003" to clean up a deck.

 

I agree
Double-check that volume measurement.
If it really has been milled that close, you are gonna be pushing it on P/V.
Make sure to mock up the engine components and check for clearance
before you bolt it up. (play dough)

You may end up needing thick head gaskets or dished pistons.

 

Is there any way that I could check the cc myself, I really don't want to have to pay another machine shop, but If I have to.... Also where can I get thicker head gaskets? I bought Felpros, but I can return them to Summitt or sell them. I really would like my compression to stay around 11.8-12.1. The new short block is assembled, with -5cc Mahle pistons so piston swaps are a no go. Any suggestions are welcome. I want to get this motor in the car, but I wanna run pump gas.

 

Measureing CC will help calculate compression, but you still need to mock it up to verify P/V clearance.
Thunderracing has .050 gaskets (stock are .039"), that will gain you a little.
http://thunderracing.com/catalog/?ac...ories&pcid=227
20-10168457 LT1 Cylinder Head Gasket, .050" Thickness (sold individually)

You need something to seal the combustion chamber (plexiglass with a small hole in it)
and something to measure water in (eyedropper). They are usually sold as a "cc kit"
http://www.speedunleashed.com/Powerh...t-p-20010.html