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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
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351w heads 1971 are they a good upgrade?

  • Thread starter Thread starter lib88stang
  • Start date Start date Jan 11, 2004

lib88stang

Founding Member
Mar 24, 2001
154
1
18
Pa
Jan 11, 2004
#1
  • Jan 11, 2004
  • #1
i got a set of 1971 351w heads and i was wondering if they would make a good noticeable upgrade and what all would need done to them to make them work.they are still complete and stock.i want to run a f cam or a trick flow cam.let me know what works with this setup...
 

mustangmuscle87

New Member
Jan 10, 2004
12
0
0
Jan 11, 2004
#2
  • Jan 11, 2004
  • #2
I understand that they have bigger valves and bigger cumbustion chambers, so you may lose a little compression. Windsors have bigger head bolts so you would need a special washer to make them work. (ARP sells that) or you could drill and tap your bock to accept the bigger bolt. I went that route and used a set of ARP head studs.
 

NKau

Founding Member
Dec 15, 2001
1,346
0
37
Jefferson, WI
Jan 11, 2004
#3
  • Jan 11, 2004
  • #3
There are actually stepped head bolts that you can buy that makes those head a simple bolt on affair. They are smaller diameter on the bottom to thread into the block and thicker on top. As the previous poster stated, you will lose some compression with those heads. I think there are better heads for the money, such as the GT40's that are a lot less hassle IMO.
 

Boss351

New Member
Jan 8, 2004
118
0
0
Quebec, Canada
Jan 11, 2004
#4
  • Jan 11, 2004
  • #4
The 69-76 heads all use 1.85 and 1.54 valves with 60cc chambers and have rail rockers (PITA studs to deal with also). I don't know if that helps any?
 
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