0.10 Ounce speed advantage?

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knotthed
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0.10 Ounce speed advantage?

Post by knotthed »

Best guesses anyone.........

What would be the speed gain by adding 0.10 oz to a car?

Location of weight is approximately .625" in front of rear axle.

Track, Freedom Aluminum 32' Micro Wizard Timer.

This is a fender related question, but I want to approach it based on weight first.

I did a test run with some double sided tape and fenders in the rear. I guess I should do another with just some small weights in place of the fenders then I can compare apples to apples without worrying about any weight effect.

I will reveal some numbers after I get some feedback on my question from others.
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Stan Pope
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Re: 0.10 Ounce speed advantage?

Post by Stan Pope »

Thought that I had some old simulations on that track that would be suggestive. Can't find 'em. If memory serves (it really does, sometimes), the effect was small but significant. Somewhere in the range of 0.002 to 0.003 Sec. But that was a theoretical car on a theoretical track of the size and shape of yours.

In any case, a better answer comes from taping a THIN, 0.1 oz weight centered on 0.625" ahead of rear axles and getting real timings!
Stan
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Speedster
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Re: 0.10 Ounce speed advantage?

Post by Speedster »

0.100 ounce = 2.85 grams. Hopefully my scale is somewhat accurate. Doc Jobe claims 1 gram light equal an 1/8" slower at the finish line. 2.85 grams would result in a little less then 3/8".
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davet
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Re: 0.10 Ounce speed advantage?

Post by davet »

There's a vid on Youtube doing this exact test and it showed IIRC .005 with just rear fenders.
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