Lightwheels improvements

Postby plum-crazy » 07 Jul 2010 6:33

Hello guys.
I'm looking for the net to know about lightweight wheels improvements at the track.
Do you know any site to look?
I just purchased a 15x9 Weld rear set with a Quick time Hoosiers. The pack is really lighter than the original. I'm going to weight both today.
I have several doubts at front. Maybe 15x5 or 15x6.

On the other side I'm not sure about the front tires, due most models are low weight rate.

Once installed they really lower ET times? Probably improves the 60ft but 0.1 at 60ft are 0.3 at quarter, really?

Thanks, I wish the threat will be interesting. :s017:
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Re: Lightwheels improvements

Postby dave-r » 07 Jul 2010 7:44

plum-crazy wrote:Once installed they really lower ET times? Probably improves the 60ft but 0.1 at 60ft are 0.3 at quarter, really?



Yes really.

It is not just the weight that is the issue. It is the force required to spin the wheels up to high speed. A lighter wheel takes less power to spin up.

There is no easy way to calculate the advantage for a particular car as so many other factors mask the effect such as brake pad drag, tyre width and pressure, track surface, aerodynamic effects etc.

But lighter is always better and a little less weight in every part of the car all adds up to quite a lot.
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Postby plum-crazy » 08 Jul 2010 14:29

Hello Dave.

Pads is not in my head this moment, just wheels and lower weight.
Probably I'll go to the R/T hood. Lightweight pin hood amd probably the trunk lid too.

On the other side I have a question about tires.
Yesterday I measured the wheels and are 15x10 not 15x9. This tube type wheels have any special way to fit?

A friend have the same combo and he fitted the tire to the wheel with several screws. He says that the rim could spins more than the tire and break the valve. Is it true? I'm on a trouble because if this is right could be dangerous if not, I prefer keep the wheels without holes.

Thanks to everybody.
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Postby dave-r » 08 Jul 2010 15:26

Big engine power + very good tyre grip can sometimes = tyre slipping round on the wheel.

How much engine power and grip you need before this becomes a serious possibility - I don't know.

This is only a problem with tubes inside the tyre of course.

Yes you can put screws into the edge if the wheel and tyre to hold it. Or you can get wheels that clamp the edge of the tyre to the rim.

I don't bother. I am only making around 450hp at the rear wheels. No sign of the tyre slipping even at only 10psi. I think you need to talk to people that race powerful cars like yours and see what they are using.

Moparts race forum might be the best place to ask this one.
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Postby plum-crazy » 09 Jul 2010 7:45

Thanks Dave.
Don't think I have more much HP than you, I don't put the car on Dyno, maybe around 500 at RW.
I 'll check forums, yesterday I read FAQ at M/T tires site and I always learn something new.

Look

http://www.mickeythompsontires.com/faqs.php
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Postby dave-r » 09 Jul 2010 8:16

Yes of course the way to check if you have any slippage is to paint a mark on the wheel and slick so you can see if they are moving in relation to each other.
But if you have a tyre suddenly deflate on a run when you are trying it out then that could be too late.
So maybe just do some short hard launches and see if you have any movement before you try a full length pass.
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Postby plum-crazy » 09 Jul 2010 13:05

dave-r wrote:But if you have a tyre suddenly deflate on a run when you are trying it out then that could be too late.


YES! That's what I mean. We don't know the real HP about cars running tube types without screws, maybe 300HP is not a problem and we are at the edge, the probably dangerous edge of the question.

I prefer the safety than the experience, most of cases as you say, too late under hard acceleration.

Thanks, I'm going to do it...
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