Weight vs ET.

Discussion in 'Manton Push Rods Top Alcohol Tech Questions' started by jody stroud, Apr 21, 2018.

  1. jody stroud

    jody stroud ZOMBIE Top Dragster

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    How much does 40 to 50 lbs affect ET in the 1/8 th mile and 1/4 mile?
     
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  2. Ryan Van Dyk

    Ryan Van Dyk New Member

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    An old rule of thumb from when my dad used to race pro stock here in Australia was 1/10 over the quarter for every 100 pound
     
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  3. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    I don't think it is quite a tenth. I have always figured it's worth .04-.05 to the 1/8 and .06-.07 to 1/4 for 100 lbs.

    Probably another .01 or so once you figure out how to make it work better with the lighter car.
     
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  4. aj481x

    aj481x Member

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    You also have to consider the amount removed as a percentage of the total weight.
     
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  5. BEDNAR1320

    BEDNAR1320 Member

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    Fill your tires and chassis tubing with Helium! ;):D
     
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  6. Ryan Van Dyk

    Ryan Van Dyk New Member

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    Would depend on the car, my dad used that as a guide in Aussie Pro Stock at 2300 pound and 800hp back in the day, my blown dragster at 2100 pound and 1700 hp would lose less if you added 100 pound to it
     
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  7. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    I think as you get more horsepower, you mitigate some of the effect.

    I think you start seeing more of an effect in terms of how it is easier to move a lighter car in terms of chassis set up and keeping the tire happy.
     
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  8. Mike Canter

    Mike Canter Top Dragster

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  9. greenracing

    greenracing Member

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    I think the math assumes that the car is glued to the track and will perform the same before and after the weight change.

    I had an Anglia with a blown Donovan in it. I added 100lbs to it and it actually picked up because it helped plant the tires better with the ridiculously short wheelbase.
     
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  10. Mike Canter

    Mike Canter Top Dragster

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    Of course it assumes it is glued to the track the same as it was before the weight was taken out.
     
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