BIG BORE DOME SIZE WHAT IS BEST?

[powertripn]

HI GUYS, I'M BUILDING MY FIRST BIG BORE MOTOR AND LOOKING FOR SOME OPINIONS ON DOME SIZE.I'M NOT AGAINST RACE GAS IF THE POWER INCREASE IS WORTH IT.IT'S A 4MM LONG ROD,68MM PISTONS, DUNE PORTED , COOL HEAD, 35MMPWK, V FORCE3,TRINITY OOF PIPES,THANKS IN ADVANCE

[firebanshee]

My 21cc domes on my motor pump 180 psi at sea level.