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Old 08-30-2005, 04:55 PM   #1
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Exclamation lbs. vs. the stopwatch.

How much does weight cost your car in times? Say your 5oz. over weight how much does that equate to in track time? .1 seconds or .2 ? I know in karts that roughly, 10lbs over weight is roughly .1-.2 seconds on a 40-50 second track. I also have done my fair share of all kinds of racing and know there isn't a set time difference but a rough idea would be nice. If 10 or 20 lbs makes a difference in my 2900 stockcar with 550HP then 5 oz. has to make a difference in a 3.5 lb car with 100 watts of power. Thanks for any help you can provide.
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Old 08-30-2005, 05:24 PM   #2
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its hard to say, there alot of factors that come into play. setup, tires, batteries, motor ect.. these factors are all the same in every type of racing i guess it all depends on syle of driving and having a clean race. i'm sure you are not that far off on your numbers. i can tell you that going from 3300 to 3800's i could tell the differance in weight with my lap times but i had to compinsate for that to bring it down. and im only talking under a second over the duration of 5 min. but every tenth helps
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Old 08-30-2005, 05:58 PM   #3
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David, 5oz over on these car's is quite bit. Not knowing for sure, but if you're running perfect laps one after another, I'd say you're looking at at least .2-.3 sec just from that extra weight. Now only 1 oz over, you'll probably never notice.
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Old 08-30-2005, 07:28 PM   #4
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5 oz is about 142.5 grams over 1500. A full motor heatsink only weighs 20 grams. If it's not directly affecting your lap times, then you could still get a lighter car and put that extra weight to use. Like running fans, heatsinks, or aluminium hopups.
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Old 08-30-2005, 07:32 PM   #5
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Though not in the proper forum...but maybe this will answer your question. Having a CW Sprinter for Dirt Oval, I am able to remove or add 6 ozs of weight at will by the battery I choose. LiPo or Nimh....

Not making any changes to the car, I was able to pick up 2-3 tenth of a second per lap, with a 10x2 motor. With the loss of 6 ounces the car got a bit squirrely, picking up a pretty evil slide. Once I had gotten the car adjusted 3-4 tenths per lap is about average.

On asphalt, yeah, I tried this too! Again not making any changes to the car, I can't tell you, the car refused to turn going in! Once I got the push adjusted out, it would slide, sort of like flat tracking ... You know the rest, so I gave up and put Nimh back in it!
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Old 08-30-2005, 07:36 PM   #6
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Quote:
Originally Posted by Hick
Though not in the proper forum...but maybe this will answer your question. Having a CW Sprinter for Dirt Oval, I am able to remove or add 6 ozs of weight at will by the battery I choose. LiPo or Nimh....

Not making any changes to the car, I was able to pick up 2-3 tenth of a second per lap, with a 10x2 motor. With the loss of 6 ounces the car got a bit squirrely, picking up a pretty evil slide. Once I had gotten the car adjusted 3-4 tenths per lap is about average.

On asphalt, yeah, I tried this too! Again not making any changes to the car, I can't tell you, the car refused to turn going in! Once I got the push adjusted out, it would slide, sort of like flat tracking ... You know the rest, so I gave up and put Nimh back in it!
Was that a 7.4v lipo and a 7.2v nimh?
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Old 08-30-2005, 08:21 PM   #7
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I know in oval my car was about 36.5 oz I was turning 47 laps even with practice stuff in the car. I added lead to the required 40 oz and could only muster 46 laps even with my best motors and batts. The car was good too, I TQ'd this national race.

so it does matter but to what extent is tough to predict.
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Old 08-30-2005, 08:25 PM   #8
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Quote:
Was that a 7.4v lipo and a 7.2v nimh?
Yep!
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Old 08-30-2005, 08:35 PM   #9
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Hey Dave, Great meeting you at the track last week

I added a 25 gram bar down the center of my old XRay and it made the car feel "lazier" The car didn't transtition, steer or accelerate as well as it did without the bar. It added roughly .3 per lap to my times.

-Dan
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Old 08-30-2005, 09:06 PM   #10
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Quote:
Originally Posted by BlackKat
Hey Dave, Great meeting you at the track last week

I added a 25 gram bar down the center of my old XRay and it made the car feel "lazier" The car didn't transtition, steer or accelerate as well as it did without the bar. It added roughly .3 per lap to my times.

-Dan

Was it on the upper deck?

If you don't have to add weight, DON'T. If that weight isn't on the upper deck, then there must be another reason that you lost 3/10ths per lap. That's a huge margin to lose over 25 grams. Which is roughly the weight of a clip-on heatsink.
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Old 08-30-2005, 09:08 PM   #11
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My old yok ssg was 1620 grams. I was running 15.6 laps at the fastest. My new Yok LCG is 1460, 1500 after lead weights. My fastest lap has been 15.1
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Old 08-30-2005, 09:23 PM   #12
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Quote:
Originally Posted by ChadCapece
If you don't have to add weight, DON'T. If that weight isn't on the upper deck, then there must be another reason that you lost 3/10ths per lap. That's a huge margin to lose over 25 grams. Which is roughly the weight of a clip-on heatsink.

It was on the lower deck. My laps went from 15.5-16.0's to 15.7-16.2. My average dropped by like 2-3 tenths a lap
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Old 08-30-2005, 09:30 PM   #13
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my ssg was 51oz, my cgm was 53 something, the cgm was faster. had nothing to do with weight, just a better car.
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Old 08-30-2005, 09:34 PM   #14
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Quote:
Originally Posted by Turtlemaster
my ssg was 51oz, my cgm was 53 something, the cgm was faster. had nothing to do with weight, just a better car.
Have you driven a LCG yet? It's crazy fast. Just about everyone on the Yokomo thread that has that car is ripping it up. Haven't heard one complaint
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Old 08-30-2005, 09:55 PM   #15
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Thanks for all the responses! I have gotten about 45 oz. off my car and with stock foam setup I hope it helps. With stock foam there isn't much power vs. grip so hopefully I can pick up a tenth or so. Over a 5 min race that is quite a bit.

I am trying to get to the 51oz. minimum for the Vegas race. Right now I am within about 20 grams which I don't think will make much difference but would always be nice to have to add weight where I need it.

With 60 or so guys in the class every tenth is going to matter!! .

Anyone have tips for losing some LBS?? Thanks again guys.
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