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How aggressive would you go for weighting on a Scout car?

Discussion in 'Building tips' started by KyleBCostco, Jan 1, 2018.

  1. Thinkin'Bout Racin

    Thinkin'Bout Racin League Racer

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    The answer to your question, ....how important is it to even out the weight on the back wheels? The answer is I don't know for sure. There are so many factors that have an effect on the car, that how the rear is weighted may/will change based on all of the other factors involved. All a person can do is develop a hypothesis and then test to see if you are headed down the correct path.

    Your cars that have done well, may like the weight bias you have based on the COG, amount of steer, COM, and wheelbase.

    I am going to repeat this: Everything on a build has some effect on everything else. Keep this in mind as you are working on your hypothesis.

    Yes, I find this discussion interesting ...Good Luck.
     
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  2. KyleBCostco

    KyleBCostco Pinewood Ninja

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    Well it didn't wind up as aggressive after paint and vinyl covering the bottom cavities. I think my son and I just need to add a bit more steer than last year's car (4") maybe 5". It looks as though the car will wind up very close tonthat 3:2 ratio across the back axle. Thank you all for your input!
     

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  3. Thinkin'Bout Racin

    Thinkin'Bout Racin League Racer

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    I figured based on the amount of surface area in front of the rear axle, that you would be adding some nose weight with paint.

    Steer ....if you still have last years car and know what the steer is, then weigh it like this years car. Remember that if you have noticeably less weight on the FDW on this years car, that applying the same amount of steer as last year, will result in less bite because of the weight difference. You can further confirm this by checking your COG on both cars. Again if this years car has a more aggressive COG, it may welll need a bit more steer.

    All of that to say, make sure you get enough steer to avoid the wiggles. Again, 1-2" of more steer than you need will only cost you a few thousands of a second. One wiggle, caused by not enough steer or an unstable car in the next lane will cost you a hundredth. If you have one wiggle, then normally you end up with 2 or 3, thus costing you 2-4 hundredths. I know this concept was REALLY hard for me to except. It just seemed like it would cost more time by having too much steer. I can say for a FACT that a wiggle or two cost WAY more time!

    Again, Good Luck and let us know how it goes.
     
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  4. KyleBCostco

    KyleBCostco Pinewood Ninja

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    Hi guys,

    Sorry to bring up my old post once again but I am concerned about going too light on the DFW again this year...

    Same rules except completely stock wheels, still stock wheelbase, stock axles, 5oz...

    Thoughts? We are using Tx Chemist full Monty for weight...
     

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  5. Thinkin'Bout Racin

    Thinkin'Bout Racin League Racer

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    If you are confident in your drill, then run it. The numbers look good. You will also add maybe a 0.1 - 0.15 of a gram to that DFW with paint. You have enough surface area area in front of the front axle that paint will add a little weight.

    COG looks to be around 0.422 in front of the rear axle. A bit on the aggressive side ... see what that DFW weighs after paint.

    Looks good!!!
     
  6. TRE

    TRE PWD Royalty Pro Racer Pro Race Winner

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    I wouldnt go below 13 grams on your dfw...if you are running stock axles i would put more there
     
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