wat domes to use

[r1racer]

i bought a pro design cool head with 18cc domes and was wondering what size domes i should run if i want to run pump gas. my elevation is 1500 feet

[cdwood37]

I would say 21cc at your elevation to be safe and 20cc to walk on the fine line, my vote is the 21cc unless you want to run race gas tehn you could go to a 18cc.

[lowriderb]

do you have port work?

 

if so that would make a difference in the compression..

with out port work 20cc domes should put you at about 155-160psi,

 

if you have port work depending on the porting 18cc domes may only give you 145 or so.. but that depends on the type of port work involved..

[r1racer]

yeah i have a 404 big bore kit with porting

[steveodo]

I would go with the 20cc an whats your compression with the 18cc ?

[njbanshee]

You should put the 18's in and run race gas. just my .02

[lowriderb]

with the big bores you are going to have different dome sizes than the standard sizes..

 

20's with that bore are probably small enough to keep up with pump gas.. but look into that more..