20cc cool head dome

[07preddy]

will a pro design cool head with a 20cc dome hurt my stock bottom end?

[04blasterkid]

i wouldnt think so, but you have to run race gas with anything under 21cc... im almost pos.

[Scott-300ex]

Do a compression test before you run race gas. 180psi and up then run it.

Your bottom end will be fine.