Posted by Ray Wood on December 23, 1999 at 11:03:57:

In Reply to: compression ratio posted by tertiusm on December 23, 1999 at 01:20:09:

The 7:1 head is 3.7 inches thick. The 8:1 is 3.6 inches thick. If you have a 7:1 you mill it about .085 to covert to 8:1.

Wise Owl