a stock "848" head is 77 cc. Hope your testing will verify that.
It would surprise me if it's that small. The combustion chamber on a low-compression 350 V8 is 76 CC, and just an eyeball comparison of the stovebolt chamber seems to indicate it's considerably larger. That big hole up close to the exhaust valve takes up a lot of space!
Denny, it's pretty simple, just a 1/4" thick piece of clear Plexiglass with two holes in it, and a 100CC burette. The Burette is inserted into one hole, and the other one is an air vent. The plastic is sealed down to the head with Vaseline, and dyed alcohol is the test medium. I use Methanol from the hardware store (shellac thinner) with a few drops of blue food coloring in it. Run the chamber full, let the air escape, and measure the volume used when the chamber gets full. Easy! Of course, a clean combustion chamber with good-sealing valves is a must! Remember to put the spark plug in! I'll post some pics the next time I've got the system set up.
Jerry
