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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • Fox 5.0 Mustang Tech

head differences

  • Thread starter Thread starter lil bull
  • Start date Start date Mar 4, 2008

lil bull

New Member
Nov 27, 2006
10
0
1
Arlington, Ohio
Mar 4, 2008
#1
  • Mar 4, 2008
  • #1
do any of you guys know if the gt 40 and the gt40p head parts will interchange with each other, as longas the valvle sizes are the same. Like springs, roller rockers etc?? Thanks
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Mar 4, 2008
#2
  • Mar 4, 2008
  • #2
The P springs are worthless. Throw them in the trash and pick up some different springs that will accept a cam with more lift than around the .500" the stock springs are capable of before you run into coil bind (if you're referring to owning a set of P heads). The valve sizes are different between the two, but the stems are the same size. The regular GT40 has 1.85/1.54 valves, compared to the 1.85/1.46 for the P's. The rockers will interchange between any of the stock pedestal mount heads.
 
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