How to identify gt40 heads

Discussion in 'Fox 5.0 Mustang Tech' started by 5.0 Fiend, Aug 29, 2004.

  1. I have heard of gt40 heads being a good increase over stock, and that they came on some explorers. My question is, what years did the gt40's come on explorers, and how do I identify them?
  2. I believe all 5.0 V8 Explorers got the GT-40P heads. Which are different from the GT-40 head. The P head has the spark plugs coming out at a different angle, which requires special headers. FRPP sells the headers you would need.

    I'm pretty sure the GT-40 heads only came on 93-95 Cobra's and some crate motors. For a long time you could buy them dirrect from FRPP (then called SVO). A couple years ago they were discontinued.

    GT-40P heads can be ID'd by the "GTP" on the head. According to this the GT40 has "GT" cast where the "GTP" is.

    See this link for more info on GT-40 vs. GT-40P:

  3. Thanks, that was the answer I was looking for.
  4. GT40s also came on Explorer through mid 94. GT40s have 3 bars on the end and GT stamping, instead of the 4 bars and GT40P stamping. My heads came from a 94 Explorer. The Cobra heads have a smaller combustion chamber, raising the compression, as compared to the over the counter or explorer GT40s, hence I had mine milled .025. If you get the GTs, make sure you look into better springs, unless you run the stock camshaft.
  5. Regular GT40's came on the Explorers through 1996. After '96 they went to the GT40p heads. Im selling a set of GT40's I got off a '96 Explorer. I think some '97's had GT40's and some had the GT40p's.
  6. Correctamundo!!!

    Also, GT-40's have 1.84/1.54 valves versus GT-40P's 1.84/1.46 valves. As where stock E7TE heads use 1.74/1.46 valves.
  7. Not quite - regular GT40's came on Explorers through the first couple of months of 97 model production -- somewhere around build dates in Oct.96 the swap was made to GT40P's. That means 95, 96 and the first month or two's production of 97's had GT40's; the rest had P's. Look for the 3 parallel bars cast into the ends of the heads. I don't believe the 5.0L was available in the Explorer until the 95 model year - 94 models the only engine available was the pushrod 4.0L v6.