1993 3500 CC Dually. Originally a 6.5 Turbo. now it has an 86 military 6.2 with a new GM8 Turbo and the 6.5 intake and exhaust.

I'm do the research on rebuilding my engine before I put my truck down and I need a few questions answered.
1. What is the head chamber size? Do the different heads have different chambers?

2. I'm not sure which pre cups I have, but does anyone now the volume size of those?

3. Do anyone know the CC displacement of the top of the piston?

I'd like to know what the static compression will be before I commit to keeping my parts.