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  • 1974 - 1978 Mustang II Talk & Tech

GT40 vs. GT40P for Mustang II 302

  • Thread starter Thread starter joeythesaint
  • Start date Start date Dec 4, 2006

joeythesaint

New Member
Feb 9, 2003
402
0
0
Seattle
Dec 4, 2006
#1
  • Dec 4, 2006
  • #1
I just want to make ABSOLUTELY SURE I'm right on this before I shell out the dough.

The GT-40 head will bolt up to the Hedman Hedders for a MII. Correct? It is the GT40P head that will not.

I have used the search function; I am posting this so there will be a definitive GT40 thread for the search.

Anyone here running GT40's?
 
C

cobraii351

Founding Member
Jan 10, 2000
1,104
4
39
Altoona, PA
Dec 5, 2006
#2
  • Dec 5, 2006
  • #2
The GT40 exhaust bolt pattern is the same as any other SBF head. The exhaust bolt pattern is also actually the same on both heads. It is the revised spark plug angle/position that is the issue with the GT40P head. All the Mustang II headers were made/designed with the old plug angle in mind. There are some special "short" spark plugs made but there is no guarantee that they will even work. They also may work as well. I'm not sure if anyone has tried it or not. If someone had access to the heads and headers and could do some fitment testing that would be great for the community.

Tim
 

2muchtime

Founding Member
Jan 30, 2002
890
1
16
MA.
Dec 5, 2006
#3
  • Dec 5, 2006
  • #3
you are correct..
the original gt40 heads will fit with those headers
the gt 40 p heads are from an explorer (discontinued in 02) the reason they dont fit easily is because of the sparkplugs.
the originals are harder to find these days.
 

Blue Thunder

15 Year Member
Mar 20, 2004
1,003
55
68
Upstate New York.
Dec 5, 2006
#4
  • Dec 5, 2006
  • #4
I wonder if those shorty spark plugs plus a 1/4" spacer between the head and flange would yield enough room.
 
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