CC Valve Relief ??

I BOUGHT A 30 OVER 460 SHORT BLOCK, IT HAS TRW 2443 PISTONS SPECS SAY 12 CC DOME, THEY PUT A VALVE RELIEF IN SO 72 CHAMBER HEADS WOULD WORK,, MY QUESTION IS , HOW MUCH MATERIAL MIGHT THIS HAVE TAKEN AWAY FROM THE 12 CC, AS THE ENGINE IS TOGETHER NOW, ANY IDEA'S , WITHOUT HAVING TO PULL IT APART..IM TRYING TO FIGURE FOR COMPRESSION.. THANKS SAM....

They come from with a valve relief already in them, I have read that the old TRW's have larger valve reliefs then the new speeed pros. Are you saying they cut yours bigger? They should be around 13.75-14:1 with a 72cc head, be sure to check yor piston to valve clearance.

L2443's date back to the 1980's and have had several revisions over the years between the different parent manufacturers of that piston and the part number was not changed to reflect those revisions. For this reason, we cannot tell you exactly what the dome volume or dome height is. If you are in fact looking at the specs that specify the 12.1 cc dome/0.400" above the crown at its peak, then you may need some revised data.

Most L2443s you will find these days are 0.332" high and have about 16 ccs of dome, less the 2 ccs for valve relief for a total positive dome volume of about 14 ccs.

Paul