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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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Header bolt lenght for y-303's??

  • Thread starter Thread starter fox racer
  • Start date Start date May 15, 2005

fox racer

Member
Jun 22, 2004
577
0
16
Staten Island, NYC
May 15, 2005
#1
  • May 15, 2005
  • #1
ok, i just bought stage 8 header bolts, but i got the ones that are stock length, (1 inch) and i kno with soem aluminum heads the stock headerbolts dont work because the dont fit... will these fit? i was lucky enough to find a stock header botl in the garbage and it looked liek the bolt bottomed out with like a quarter inch of space. im using bbk shorties... will the 1 inch bolts be ok? yes right?
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
95
99
PA
May 15, 2005
#2
  • May 15, 2005
  • #2
I find most aftermarket alum heads take the shorter bolts, believe they are 3/4"
 

fox racer

Member
Jun 22, 2004
577
0
16
Staten Island, NYC
May 15, 2005
#3
  • May 15, 2005
  • #3
thats what i thought... but the stock bolt nealry botoms out... and i was told i didnt need new bolts, so im hoping this is ok
 

fox racer

Member
Jun 22, 2004
577
0
16
Staten Island, NYC
May 15, 2005
#4
  • May 15, 2005
  • #4
worst come to worst ill grind them down as needed.
 
I

Insane3D

New Member
Jul 21, 2004
310
0
0
May 15, 2005
#5
  • May 15, 2005
  • #5
The FRPP aluminum Y and X heads both use the standard header bolt size that the stock heads do. They are 3/4" long, not 1". I saw some people suggest using 1" bolts, but I called Ford and they said they "might work". The BBK headers I just took off, and the FRPP ones I'm putting on both came with 3/4" long bolts.

You need to be careful with 1" bolts, if they thread in too far you can damage th threads I believe...

 
H

hrspwrjunkie

Member
Dec 15, 2004
165
0
18
May 15, 2005
#6
  • May 15, 2005
  • #6
I've used both on X heads. 1" did work, but barely. They did bottom out, even with the thick header flange on a BBK header. I chose to go with 3/4" and was much happier.
 
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