explorer heads aka gt40s

Discussion in 'Technical' started by justin has a 74, Oct 1, 2009.

  1. justin has a 74

    justin has a 74 Maverick bandit official

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    i see no problem with that:D
     
  2. scooper77515

    scooper77515 No current projects.

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    Nope, none at all!

    I spent a couple years dealing with that hassle and finally just gave them away and bought a set of non-P GT40 heads.
     
  3. maverickfever

    maverickfever maverickfever

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    Does anyone have an idea of why they changed,and what,on these heads?
     
  4. scooper77515

    scooper77515 No current projects.

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    The GT40Ps came on later Explorers, with special "headers". I use "headers" because the weren't really headers. But they were tubular exhaust pipes that cleared the plugs. They won't fit inside our shock towers.

    The changes were better flow from spark plug to xhaust port, and a better spark plung location, being almost right into the middle of the combustion chamber. 10 degrees off right on center.

    The gt40 heads are better because you can use them on a regular setup even though you lose a little flow (compared to the P heads). The pugs are at the normal location with a much better flow pattern.
     
  5. my70mav

    my70mav Member

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    i paid 300 for a complete explorer engine from throttle body to oil pan with gt 40 heads.i pulled the heads and sold all the rest to a foxbody mustang guy for 350.wasn't even looking for any of it,i went to find a door for my buddies b2000 pickup.when i found the engine i made him wait there so no one could get the stuff while i went home for more tools.
     
  6. chirt

    chirt Carlos Hirt

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    I got the Gt40Ps on mine for over a year now and no problems Yet!:)
     
  7. scooper77515

    scooper77515 No current projects.

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    If you put them on and just leave them alone, then no problems.

    But if you are like me and constantly messing with stuff, checking plugs, etc, then they get to be a hassle.

    BUT!!! I hear that they work fine with stock exhaust manifolds, but never checked to verify. It is just the headers that are a hassle with the P heads.
     
  8. chirt

    chirt Carlos Hirt

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    That's true,I leave them alone :bouncy: I have a set of stock manifolds and a set of shorty headers so If I ever need to mess with the plugs I'll try these other manifolds/headers.
     
  9. jayss10

    jayss10 This is Minerva

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    ok another ? ,i have 1970 351w heads off a 4 barrel motor ,how much better would gt40 heads be ,say i was making 350hp now what would i get with the gt40 heads ? anyone know holla ..........
     
  10. scooper77515

    scooper77515 No current projects.

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    Are those stock heads, or do they have work done on them?

    An internet search will get you flow numbers for those stock heads, but if they have work on them, then there is no telling what you have.

    GT40s stock flow 193 intake, 130 exhaust.
    GT40Ps stock flow 193 in, 142 out.
    351 stock flow 189 in, 115 out. But, with good work, they are good for 224/172.
    E7 stock flow 155 in, 122 out
     
  11. justin has a 74

    justin has a 74 Maverick bandit official

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    found some gt40 p heads today on a 97 exlorer but i want gt40 ones lol
     
  12. jayss10

    jayss10 This is Minerva

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    mine are stock ports ,all i ha ve done to them is put guide plates and 3/8 studs to make them adj.,i was gonna port them this winter but if gt40 heads will out perform them then ill go with them,i fell with my setup in my maverick right now i can runs 7.40s ,i want to be 7.0s to 6.80s ,and still be streetable,right now im 8.5 to 1 comp ,500 lift hyd cam,victor intake,750 carb,4000 stall 4.10 gears 3 inch exhaust with 1 5/8 headers
     

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