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AndresRS01
04-24-2001, 12:59 PM
This is really getting my attention since I have reduced the weight of my car . I had an argument w/ my friend about the influence of the weight of the wheels on the performance of the car.
Does somebody know w/ realistic numbers what is the equivalence between one pound reduced from the body of the car, one from the wheels&tires, and one from the flywheel..?
I tried to do some research without success..

Thanks

Andres

[This message has been edited by AndresRS01 (edited April 24, 2001).]

m750
04-24-2001, 03:02 PM
thanks... some good reading. This is they type of info I come to the site for. Thanks
Aaron

ColinL
04-24-2001, 03:19 PM
Perhaps I'm an incurable skeptic -- OK, I know I am http://www.i-club.com/ubb-files/smilies/wink.gif-- but I don't see a great deal of change in the acceleration data. In fact, if the data is based on only 3 runs (once each for each wheel & tire combo) I don't think the results are even repeatable-- the differences in ET & trap speed should be well within the car/driver's repeatability. (Pro Stock can go 10 runs within .1, but a magazine driver in an Integra probably can't.)

The bigger factor is how much cornering and braking performance was gained by going to the wider, lower profile and (more importantly) stickier tires.

[This message has been edited by ColinL (edited April 24, 2001).]

SHADOWES
04-25-2001, 01:29 AM
saving weight on wheels and tires makes a huge difference but it depends mostly on the actual rolling weight of the combo a wheel can be very heavy but have most of the weight near the center or it can be very light but with a large amount of weight in the rim and the two wheels will have very different rolling weights even if they have the same static weight. SCC did an article about this a few months back I will read over it and post more latter if I can find it. I think it came out to something like 50 pounds off of the car shaves like .05-.1 of a second off of a 1/4 mile run.

tmat3
04-25-2001, 01:35 AM
I think it was something like 1 or 2lb of wheel weight equals to 9lb of total car weight? So, total of 36 extra lb. SCC had this topic last year.

<-------- Look at this! I hit 1000 posts!



[This message has been edited by tmat3 (edited April 24, 2001).]

gavin
04-25-2001, 01:49 AM
There are actually two factors which are relevant - Unsprung Weight, and Rotational Inertia.

I did a quick search and found this article which explains both fairly well.

Wheel Analysis (http://integra.vtec.net/wheels/lightwheels.html)

Take notice of the data from Motor Trend, at the bottom. You guys stepping up tire/wheel sizes aren't necessarily doing yourself any favors.