Fox T-Bird/Cougar Forums  

97 should be the non P head.  P heads came about with the new style lift gate and grill design.  Grab the heads, intake, t/b and swap away.  Ford Motor Sports headers for P heads in a fox are about $250, and they are stainless.  Not a bad price at all.

Can you spot a GT40 engine over a GT40P engine just by popping the hood?  I can.  You don't have to look at the heads.

If it's a GT40P head then yes you need the FMS stainless headers. They are nice but they do hit the driver's side mount. I had to put a slight ding in one of the header tubes and grind down the top of the mount a bit. I'm running GT40P heads and I like 'em.

You don't NEED the FMS headers. BBK and Mac shorties work if you use 90* spark plug boots.

That subject is still in high debate.  There is no definitive answer that I have found.

I pulled non P heads off of a 97 Mountaineer and IIRC I checked the door tag and the truck was built in 97 not 96.  There were no 96 Mountaineer's, it was a 97... And it had Non P heads. 

They may look similar but the 97 and 98 Explorers and Mountaineers have many differences.  Front end, liftgate, radio style and harness, hell even the sway bar is attached differently on a 98 than a 97.  From what I've read, and not from Mustang guys on Mustang forums is the P heads may be on 97 models with a late 97 build date.

Can you spot a GT40 engine over a GT40P engine just by popping the hood?  I can.  You don't have to look at the heads.

I suppose there is no difinitive answer as to when they switched to the "P" heads.  I pulled a set of "P" heads from a '97 Exploder...seems like they were all over the place in '97.  I thought, for certain, that '97 was the year they changed over to the "P" heads...guess I was wrong.

You don't NEED the FMS headers. BBK and Mac shorties work if you use 90* spark plug boots.