Noss Head

[jrm312]

i have a noss head with 22 domes in it at aprox 600 to 800 ft above sea level

and a high end trail port should my compression go up or down with a port job????

its at 151PSI now

[Cotton eyed Joe]

i have a noss head with 22 domes in it at aprox 600 to 800 ft above sea level

and a high end trail port should my compression go up or down with a port job????

its at 151PSI now

Depends on if your exhaust port gets raised. PSI is determined by how much volume is trapped after the piston closes over the exhaust port.

[Oilsmoke]

Thats the beauty of a Noss Head it can be what every you need it to be.

if you port it more and riase the exhaust timming, Like Cotton Eyed Joe said, you can get 20 cc domes to off set the lost compression.

Edited May 11, 2004 by Oilsmoke

[@@banshee_rider@@]

my compression is 155 after porting i installed the 21cc domes. i am just thinking of getting a 20cc domes. do you think that i have to run race gas if i installed a 20 cc domes and would it gives me more hp.

[sredish]

my compression is 155 after porting i installed the 21cc domes. i am just thinking of getting a 20cc domes. do you think that i have to run race gas if i installed a 20 cc domes and would it gives me more hp.

if your @ 155 with 21cc then you'll be needing race fuel with 20cc, at least a 50/50 mixture.