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

Gt40p heads with stock springs

  • Thread starter Thread starter f8tlfiveo
  • Start date Start date Apr 9, 2012

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Apr 9, 2012
#1
  • Apr 9, 2012
  • #1
I put a set of reman gt40p heads on my car about a year and a half ago. I did not change the springs when I put them on. I just bought a set of crane beehive springs to replace the stock springs. Do you think I left any hp on the table by using the factory springs? My last dyno was 260 hp 300tq at the wheels.
 

NIKwoaC

中國製造
15 Year Member
Oct 31, 2006
5,525
943
214
Chengdu Province
Apr 9, 2012
#2
  • Apr 9, 2012
  • #2
It is possible. You'll now have a more stable valvetrain which could mean more RPM, and RPM=power. What RPM were you seeing with the stock springs? I'm assuming stock cam?
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Apr 9, 2012
#3
  • Apr 9, 2012
  • #3
Stock cam.. 1.7 rockers.. Prob about 5200 or so... High rpm seems to lose a good amount of power
 
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