dome size

[rappy660]

hi guys, im doing a big bore 68mm bore. What cc domes should i run in order to get the highest compression on pump gas? I no i need big bore domes with a 9 degree angle

[AKheathen]

i would have to initially say stick with 21, and still add some timing on bb. however, it could be smaller, depending on the conditions. what alt. and porting do you have? timing?

[rappy660]

i would have to initially say stick with 21, and still add some timing on bb. however, it could be smaller, depending on the conditions. what alt. and porting do you have? timing?

 

they are vitos cylinders, drag port that comes from them, and triple exhaust porting. Going to do a +4 timing.

[firebanshee]

I ran a 18cc dome on a 68mil bore on methanol and rattled plugs loose. 21cc dome pumps 180psi on my cub, so if you want more than 180psi then try a 20cc dome. My dome angle for a blaster piston is 10deg. Sounds like you are after alot of compression for your set up. That will give you killer bottom end but sacrifice on the top end.

Edited March 4, 2010 by firebanshee