GT-40 head Q's

[Npower]

What were the specs for the gt-40 springs that came stock on the 93 cobra gt-40 heads?

 

[jtfairlane]

I don't know what lift they were good for, but I can give you spring pressure and a few other specs for the '93 Cobra GT-40 heads.

Intake: 90psi @ 1.78" (Closed)
280psi @ 1.30" (Open)

Exhaust: 85psi @ 1.60" (Closed)
264psi @ 1.12" (Open)

They were single springs with a flat-wound inner damper.

They are NOT the same as the stock springs on H.O. heads, but they DID use the same retainers, keepers, and valve guide oil-seals as the standard H.O.

 

[thumper460]

the GT40s are about 85-90 lbs installed!! For a performance spring ( hyd roller .500 lift and above) you should have WHAT the cam says to have, however the 130-140 seat 320 on the nose is pretty much right for all !! Check the classifeds for spring sets.. cool??

Just me.............................

Thumper

 

[Npower]

Thanks guys, I have a f cam laying around I was gonna toss in untill I put the new motor in in the spring, but was not sure if the oem gt40 springs would hold up for a few months.