• Mustang Forums
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Header bolt size.

  • Thread starter Thread starter SN95StangMan
  • Start date Start date Nov 15, 2007

SN95StangMan

New Member
Jul 5, 2003
1,292
0
0
Lynwood, CA
Nov 15, 2007
#1
  • Nov 15, 2007
  • #1
Need to replace a header bolt and can't remember if they are 3/8-16x 3/4" or 3/8-16x1"

I seem to remember the stock length bolts seemed to be short especially with the thick flange of the FMS shorties. Would the longer ones be ok comsiderind the large flange and I might use it with a locking washer.

*** And before someone suggests it, I really can't justify buying a whole set of locking header bolts just to replace only one of 16 bolts that has backed out in almost four years.

Thanks for the input.
 

5spd GT

"the 5.0 owns all"
Founding Member
Aug 7, 2002
9,516
6
99
Arkansas
Nov 15, 2007
#2
  • Nov 15, 2007
  • #2
If I recall, stock is 3/4" length.

What you could do is measure the depth of the hole in the heads and see how much room you have to play with, in order to go that extra 1/4 inch.
 

final5-0

Mustang Master
Apr 6, 2003
6,817
12
79
DFW Texas
Nov 15, 2007
#3
  • Nov 15, 2007
  • #3
What David said

An easy way is to stick a nail in the hole and mark it next to the header flange

If you want to use lock washers ... they work excellent btw ... be sure the
depth of the hole, the thickness of the flange, AND the thickness of the
washer are all taken into account :Word:

The ideal bolt length will be just shy of all those dimensions

You do NOT want the bolt bottoming out in the hole

I have used two lock washers in the past to take up just a bit
more slack when needed

Hey ... you just do what is needed after you scope it all out

Grady
 
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