How to "CC" a cylinder head

cc-pic-1.jpg (12308 bytes) Here we see the flat plate made from some type of Plexiglas, lexan or acrylic. I used a head gasket to mark off the holes and the area of the combustion chamber. The bolt holes as it turned out where not really necessary as the plate sealed well enough without bolting it on.
cc-pic-2.jpg (14332 bytes) Here we see the various holes drilled out. The hole in the middle is for filling the chamber with fluid. If you bevel the hole like a small funnel it will make filling the chamber much easier.
cc-pic-3.jpg (14073 bytes) The almost finished product. The white protective covering has been removed in this photo.
cc-pic-4.jpg (22465 bytes) Here we see the plate sealed against the bottom of the head using a very very thin layer of silicone sealant. The label is not really necessary.
cc-pic-5.jpg (20871 bytes) Here I have filled the graduated container with 30cc of transmission fluid. Start with an even amount like 30, 40 or 50, write it down.   Measure carefully, small amounts make a big difference.
cc-pic-6.jpg (22599 bytes) Here we see the combustion chamber filled with fluid. The small red circle is highlighting something I forget to mention earlier. This is a small hole, made with a piece of hot wire, or small drill bit. It allows air to escape as you fill up the chamber.

After I filled up the chamber to the bottom of the hole I still had 9.5cc of fluid left in the container. The original 30cc minus the 9.5cc of remaining fluid tell me that I have a 20.5cc combustion chamber.

Pretty simple, and you can save the plate for use on other engines. Remember to remove the plate from the head before the sealant hardens.