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Just did GT40P heads and intake, and a B cam. Will a bigger TB and shorties help?

Discussion in '94-95 5.0 - Specific' started by tykempster, Feb 25, 2014.

  1. Feb 25, 2014 #1
    tykempster

    tykempster Member

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    Hey everyone. New to this forum, slightly new to Mustangs and cars in general. I completed a GT40P swap a week ago, runs awesome, a lot more power. I am getting BBK shorties to help the plugs clear a bit better, and was wondering if a 70 or 75mm TB put on at the same time would help the car breath much better and what I could expect from the two?

    Here's my current engine mods:

    CAI
    GT40P upper/lower
    GT40P heads
    B cam
    Underdrive pulleys
    SCT tuner
    New distributor, plugs, wires

    Thanks!
     
  2. Feb 25, 2014 #2
    white95

    white95 Administrator Staff Member SN95 Supporter

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    Throttle body

    Go with the 70mm over the 75mm. You potentially would have enlarge the opening in the adaptor elbow [supposing you haven't done a fox throttle body swap yet] for the throttle blade to open without interferance. You most likely will see a slight increase in power, less than 5 or so. You may also run the risk of a surging idle and other driveability issues without a tune. Some cars are excellent patients and you can get away without a tune but most, like mine, get all :handz: and won't run right.


    Headers


    Anything is better than the dinky, restrictive stocker headers and you should feel a bit of difference depending on your other exhaust mods. Don't be surprised if you lose a little torque down low to gain 5-10 hp [generous estimate] in the 3000-5000 rpm range. Best way to fix this? GEARS!!!!
     
  3. Feb 25, 2014 #3
    GT Rob

    GT Rob Well-Known Member

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    70mm
     
  4. Feb 25, 2014 #4
    tykempster

    tykempster Member

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    I have 3.90 gears, so that's not a problem. First gear is burnout gear now! I also have a full exhaust. H pipe and SLP LM1s.
     
  5. Feb 25, 2014 #5
    CC'S95GT

    CC'S95GT Legend

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    Welcome to the madness
    you will still have a problem with 1 plug with the BBK headers. but it's not anything that can't be overcome.
    FRPP and MAC both make P specific headers.
     
  6. Feb 25, 2014 #6
    tykempster

    tykempster Member

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    I got a really good deal on these I couldn't pass up, I read they have more clearance than the stock headers so at least I won't have to worry about burning plugs I think?
     
  7. Feb 25, 2014 #7
    CC'S95GT

    CC'S95GT Legend

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    just #7. Put a 90* boot on it and some heat wrap and you should be good.