What cc domes do I need?

[crustydemon]

I need to get some stroker domes for my Noss head but dont know what cc I need.

I got a 4 mill stroke with 66mm bore and I'm running 1300-1600 ft. Want to mainly run pump gas.

[dajogejr]

Without knowing your compression ratio, it's hard to say.

I think a stroker dome with 21cc or 22cc would be safe for pump gas.

[hercalmighty]

Im running 23cc domes with +6 timing and Im right there for pump gas. I ride mostly sea level up to 1500'.

[dajogejr]

Fine point indeed.

Without knowing the compression ratio AND timing...hard to say.

Compression ratio and timing dictate the need for higher octane, NOT cranking compression.

 

If you go by cranking compression, you're only guessing.

 

I'm not sure I understand "want to run mainly pump gas".

You either run race fuel or pump gas....unless you want to switch domes and timing when you switch fuels.

[hercalmighty]

Yeah I talked to Kevin at HJR about my domes since he ported the motor. He originally sent me 21cc domes to run on 110 octane. I couldnt afford the race fuel so I wanted to go back to pump gas. So we talked it over and he said I should be good with 23cc domes.

[crustydemon]

Thanks for the help. I'll have to figure the comp ratio. I have no cranking compression anyway cause I have no domes (it dont squeeze too tight that way)

What I meant by mainly running pump gas is that I do occasionally run race gas but only because that is what we may have on hand at the time, not for any performance gain. I want it set up for pump. Thanks again.

[dajogejr]

I need to become friends with you guys....can you occasionally have some extra methanol on hand, just in case?

 

I understand....