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  1. #1

    Default Finally got to the track

    82 GT 347 650 Quick fuel, TF 11R Heads, 5 Speed 3:73 Rear gear.

    Lots of wheel spin and tricky to launch with used up Nitto 555 tires. 60 ft times are awful but the MPH is promising. Happy to see it get in the 12s! I feel I can get in the mid 12s with better launch practice.
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  2. #2
    FEP Super Member mmb617's Avatar
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    I don't think you'll have any problem getting that combo into the low 12's with that mph. Probably could hit 11's with a good launch.
    408/T5/3.73's

    We're not fast racers, we're more what's known as half fast racers.

  3. #3

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    Quote Originally Posted by EMS_AV8R View Post
    82 GT 347 650 Quick fuel, TF 11R Heads, 5 Speed 3:73 Rear gear.

    Lots of wheel spin and tricky to launch with used up Nitto 555 tires. 60 ft times are awful but the MPH is promising. Happy to see it get in the 12s! I feel I can get in the mid 12s with better launch practice.
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    That is why I hate drag radials on a stick shift car, but you should be able to get a 1.9 on those Nitto’s if your lucky. That would give you a 12.50 easy.
    1993 triple white GT
    2004 AZ Mach 1
    2003 zinc yellow Cobra
    1983 410 Windsor tko 500

  4. #4
    Venomous Moderator Hissing Cobra's Avatar
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    Install a Line Loc, buy some bias ply ET streets, do a big smokey burnout and get that 60' down in the 1.6 range. You'll be running 11.60's - 11.80's @ 116-118 mph! I'm guessing that you have about 420 hp at the wheels. Nice!
    Last edited by Hissing Cobra; 03-01-2020 at 08:44 PM.
    Pete Slaney

    1979 Mustang Cobra

    347/T-5/4.30's
    420 rwhp/380 rwt (New Motor)
    11.49 @ 121.86

    306/T-5/4.30's (Old Motor)
    307 rwhp/278 rwt
    12.38 @ 111.38

  5. #5
    FEP Super Member erratic50's Avatar
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    A T5Z's 2.95:1 low gear might help you off the line more than a typical 3.35 low gear would with a 3.73 rear gear.

    Put some good slicks or drag radials on back and optimize pressure. Get some MM adjustable lower control arms on there. Disconnect the front swaybar links. Run around 1/2 a tank of fuel in the car to help with traction and weight transfer.

    Launch in anger and shift with your foot on the floor -- screw the thoughts of a broken transmission.

    My bet is you'll see an 11.30's or 11.40's with that trap speed if you do those things.

  6. #6
    New User Four Eyed Fox's Avatar
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    I'm a newbie here ( to drag racing a stick fox body) but i want to ask, at what rpm do you launch and how do you launch do you just let the clutch fly? I do like the comment above about "launching in anger"

  7. #7
    Venomous Moderator Hissing Cobra's Avatar
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    Quote Originally Posted by Four Eyed Fox View Post
    I'm a newbie here ( to drag racing a stick fox body) but i want to ask, at what rpm do you launch and how do you launch do you just let the clutch fly? I do like the comment above about "launching in anger"
    Every combination is different based on horsepower levels and type of tires. When I had my 306 in my Cobra (307 rwhp/278 rwt), I would do a 10 second burnout in 2nd gear and move to the line. As soon as I would stage, I would bring the rpms up to 5,000 and let the clutch fly. NO TIRE SPIN AT ALL and it would move right out.

    With my 347, the horsepower and torque are a lot more (420 rwhp/380 rwt) and I cannot let the clutch fly over 4,500 or the tires will spin. I run on the ET Street bias ply tires and they're not a full slick. If they were, I'd be able to launch at 6,000 rpms (where I make peak horsepower) and I'd run lower et's as a result. However, I may leave the stock T-5 on the starting line.
    Pete Slaney

    1979 Mustang Cobra

    347/T-5/4.30's
    420 rwhp/380 rwt (New Motor)
    11.49 @ 121.86

    306/T-5/4.30's (Old Motor)
    307 rwhp/278 rwt
    12.38 @ 111.38

  8. #8
    FEP Super Member mmb617's Avatar
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    The only way to find the proper launch rpm is through experimentation. Tires, suspension, track conditions, and available torque all enter into the equation.

    My 408 has a lot of torque down low and I never found a tire that would take more than 3900 rpm on the launch without too much wheelspin, but I could get 1.5 sixty times with that rpm. I also ran a stock T5 so high rpm clutch dumps with sticky tires would pretty much guarantee breakage. I never completely dumped the clutch but I did let it out pretty fast.
    408/T5/3.73's

    We're not fast racers, we're more what's known as half fast racers.

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