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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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GT-40 head Q's

  • Thread starter Thread starter Npower
  • Start date Start date Nov 14, 2006
N

Npower

New Member
Oct 15, 2006
16
0
0
Camarillo, Ca
Nov 14, 2006
#1
  • Nov 14, 2006
  • #1
What were the specs for the gt-40 springs that came stock on the 93 cobra gt-40 heads?
 

jtfairlane

New Member
Mar 5, 2006
468
3
0
Nov 15, 2006
#2
  • Nov 15, 2006
  • #2
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

Founding Member
Jul 24, 2000
3,022
2
56
Orange Park , Fl
Nov 15, 2006
#3
  • Nov 15, 2006
  • #3
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
 
N

Npower

New Member
Oct 15, 2006
16
0
0
Camarillo, Ca
Nov 15, 2006
#4
  • Nov 15, 2006
  • #4
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.
 
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