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  1. #1
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    Awesome HP/ET/MPH/WEIGHT Analysis and Calculator

    In case you're wondering how much weight of the car has an impact on ET or trap speeds, or if you're wondering how much hp (crank horsepower) you'd need to hit certain traps/ETs, here's a pretty awesome page with some pretty cool calculators

    I found Geoffrey Fox's calculator to be the closest to what my car is doing in the 1/4...

    What's also interesting to see is how much weight savings really play into the ET and trap speeds...they don't make a distinction between sprung vs. unsprung weight so take that into consideration..

    http://www.stealth316.com/2-calc-hp-et-mph.htm

    Here's a bit of a summary from there and an example of calculations for a car weighing 3900lbs at different power levels:

    ======

    As you can see, actual performance for the most part falls between the predictions of the LRT and Hale formulas, with the Fox formulas doing an excellent job of matching performance when engine power exceeds 500 bhp. For the factory stock car, the LRT prediction is very close to reported performance. In general, the LRT formulas tend to underestimate track performance a little for the very-high horsepower engines, especially above 550 bhp; and the Hale formulas tend to overestimate track performance at a given horspower level. In other words, for very fast cars in the 1/4 mile the LRT formulas predict more hp than is actually needed for the highest level of performance, and the Hale formulas predict less hp than is needed based on ET but are close when mph are used. At 550 bhp and above, the Fox formulas do a good job of predicting both ET and mph.

    Comparison of Formula Estimates and Actual Track Performance
    3000GT VR4 / Stealth R/T TT weighing 3900 lbs with driver
    LRT Fox Hale Typical ranges
    hp ET mph ET mph ET mph ET mph
    320 14.003 101.27 14.427 99.94 13.405 101.68 14.2 - 13.4 99 - 102
    350 13.684 104.05 14.002 102.97 13.011 104.77 13.5 - 13.0 103 - 105
    400 13.221 108.33 13.393 107.66 12.444 109.53 13.3 - 12.5 107 - 109
    450 12.827 112.25 12.877 111.97 11.965 113.92 12.9 - 12.0 111 - 114
    500 12.483 115.88 12.433 115.97 11.552 117.99 12.2 - 11.7 115 - 118
    550 12.181 119.26 12.044 119.72 11.191 121.80 12.1 - 11.3 118 - 122
    600 11.911 122.43 11.700 123.24 10.871 125.38 11.5 - 11.2 122 - 125
    650 11.668 125.42 11.392 126.57 10.585 128.78 11.2 - 11.0 125 - 128
    700 11.448 128.26 11.114 129.74 10.326 132.00 11.0 - 10.8 128 - 132
    750 11.246 130.96 10.861 132.76 10.092 135.07 10.787 133.9
    800 11.061 133.53 10.630 135.64 9.877 138.00 10.561 135.5
    Last edited by dzenno@PTF; 01-25-2012 at 12:00 PM.
    Click here to enlarge

  2. #2
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    Occording that site my car makes 525 crank hp, yea, no. lol

  3. #3
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    Click here to enlarge Originally Posted by Laloosh Click here to enlarge
    Occording that site my car makes 525 crank hp, yea, no. lol
    Depends on what calculator you use as they all use a different approximation...

    if we assume 18% drivetrain loss (as in the case of HPF for example and all their dynos) that puts you at 430whp which isn't too far off...obviously this isn't an "exact" science especially if your track is a fast/slow track and your ETs may suck due to your launch...
    Click here to enlarge

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    Click here to enlarge Originally Posted by Laloosh Click here to enlarge
    Occording that site my car makes 525 crank hp, yea, no. lol
    Your car has more hp than mine then, my car makes 514 crank hp Click here to enlarge

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    Click here to enlarge Originally Posted by themyst Click here to enlarge
    Your car has more hp than mine then, my car makes 514 crank hp Click here to enlarge
    Thats why mine pulled in 4th....YEAAA BUDDY

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    Click here to enlarge Originally Posted by Laloosh Click here to enlarge
    Thats why mine pulled in 4th....YEAAA BUDDY
    yes i have a factory dud lol

  7. #7
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    alright, who's Propain and who's JonAMG in this case here? lol
    Click here to enlarge

  8. #8
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    Click here to enlarge Originally Posted by themyst Click here to enlarge
    Your car has more hp than mine then, my car makes 514 crank hp Click here to enlarge
    546crank hpClick here to enlarge

  9. #9
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    Moved to general automotive.

  10. #10
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    Click here to enlarge Originally Posted by carcars Click here to enlarge
    546crank hpClick here to enlarge

    666Click here to enlarge

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