Unusual problem

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Nov 21, 2006 | 12:54 AM

gametech

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From: Stockbridge GA

Unusual problem

We dynoed my friend's vette with M/T DR's tonight, and couldn't keep the wheels from spinning on the Mustang rollers. The HP and Torque #'s were anything from 80-100HP lower than they were a few months ago. We noticed a lot of tire rubber splattering everywhere. We then swapped the rear wheels back to his Nitto street tires. This cured the wheelspin problems, and the dyno #'s were back to where they should be. I am just curious why the tires that hook better on asphalt won't hold on the dyno, and the tires that won't hook on the street stick to the rollers fine. This makes no ******* sense whatsoever to me. BTW, the best 60' on the nittos is 1.9 and the best on the M/T's is 1.6, so I know which tires hook better on the road.

Nov 21, 2006 | 03:55 AM

Hi Volume

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From: NoCal

dyno rollers are knurled and steel, not asphalt. Some slick/DR companies have warnings NOT to use them on the dyno...

If all else fails, spray VHT on the rollers....

Nov 21, 2006 | 07:55 AM

98SS2836

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From: Dracut, MA

Yea we have this problem with those tires too. You just have to move to the front of the rollors then they won't spin.

Nov 22, 2006 | 12:06 AM

gametech

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From: Stockbridge GA

I was just curious.

Nov 22, 2006 | 05:34 AM

98SS2836

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From: Dracut, MA

Is it an automatic

Nov 22, 2006 | 08:23 AM

dynocar

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From: Omaha, NE

I'm assuming that this dyno had dual rollers for each tire as apposed to one huge 50" drum like our Mustang dyno. Smaller dual roller dynos create much more tire heat because each roller applies all of the force at small areas of the tire as apposed to distributing the force over a more wide tire patch. Any tire, such as your soft tire compound MTs, will lose traction when overheated, which they obviously were if you were throwing chunks of rubber around the place. So putting your hard rubber Nittos on kept your tire temps within an acceptable range, creating more traction.