RPM Shift Point Recomendations........

Discussion in 'Fox 5.0 Mustang' started by Manewaymja2, Oct 4, 2009.

  1. Manewaymja2 Member

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    Hey there guys, some of you may remember this car that i spoke of buying from a guy in Kentucky a while back with a built 302 / .30 over with allot of goodies. Well i finally got the car here in Nassau Bahamas after 3 mths and here are the results on which i was wondering where should i set my shift point at for running the 1/8th mile on drag slicks.

    The Tune produced aprox. 400WHP and could have done more but kept it there due to Hyper pistons. The car is running a procharger 8psi of boost on 91 octane.
    Here goes with the dyno results and then from there maybe someone can make some suggestions on a good shift point as to get the most out of the car. Please :nice:

    RPM DJWhPw DJWhTq
    3000 175 305
    3100 186 313
    3200 198 324
    3300 208 331
    3400 218 338
    3500 229 344
    3600 238 348
    3700 251 356
    3800 262 362
    3900 272 369
    4000 287 376
    4100 300 383
    4200 311 390
    4300 321 392
    4400 330 395
    4500 339 396
    4600 348 397
    4700 356 398
    4800 362 395
    4900 370 393
    5000 375 391
    5100 380 388
    5200 385 386
    5300 390 381
    5400 392 375
    5500 393 369
    5600 394 365
    5700 390 360
  2. Cobra912 Active Member

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    need info on gears, transmission, etc to really give opinion but I would say around 5500-5600 as your data indicates. I shift my paxton 1220SL / 331 combo around 5600 where it makes the most power.
  3. dresmnkaos New Member

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    i would set my shift light at 5400. by the time you react to the light you'll be 200 rpms higher and at the peak of your HP level. if you got some pretty high (numerically) gears then i may opt. to shift a little sooner than 5400. that way you can get to the next gear quicker to increase your MPH.

    after you shift, if the rpms stay up around 3800, that thing is gonna be fun to drive.
  4. Cobra912 Active Member

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    I'm not sure I understand what you are saying here. If you have steeper or numerically higher gears, you would have to shift sooner as the rpms will climb faster or be reached sooner than a numerically lower gear but I would think you would want to keep it in the optimum power band by shifting at the same shift point? It's all variable depending on tire type, size/diameter, transmission, gear ratio etc. so each car and driver is different.
  5. Manewaymja2 Member

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    Ok the Gear Box is a Tremec TKO, The Rear Gears are 3.73's, The Tires are M/T Drag Slicks 26.0X10.0-15, Rims SPRTSTAR 15X8,5X4.5,5.5RS.

    Thinking to run the tires say 14psi??????:shrug:

    Would i want to shift at the point that the car makes the most Torque or the Most WHP?

    Thanks Guys
  6. Cobra912 Active Member

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    I run 12-13 psi in my slicks. Best way to tell is get someone to see if it spins off the line with 14 psi. And check the pressure after every run as they warm up so too will the psi go up.
  7. Manewaymja2 Member

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    OK will try the 12-13 psi.

    Would i want to shift at the point that the car makes the most Torque or the Most WHP?

    Ok the Gear Box is a Tremec TKO, The Rear Gears are 3.73's, The Tires are M/T Drag Slicks 26.0X10.0-15, Rims SPRTSTAR 15X8,5X4.5,5.5RS.

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