Tire size and Dyno results

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Tire size and Dyno results

Postby Sawfish on Tue May 19, 2015 7:31 pm

I am going to Dyno my car on Friday and was wondering if anyone could tell me whether the tire height which effects final drive ratio would influence HP/Tq readings.
I race the car on 205/50/15's but my road tires are 205/60/15's
The taller tires have a 7% larger circumference which results in a 6% reduction in revolutions per mile.

Does anyone have any Idea how this might affect chassis Dyno readings.

V/R
Chris Harris
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Re: Tire size and Dyno results

Postby Greg Phillips on Wed May 20, 2015 2:46 pm

Tire size should have no impact on your dyno results

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Re: Tire size and Dyno results

Postby Don Middleton on Wed May 20, 2015 4:08 pm

Chris, I had the same concern about tire size as well as tire/wheel weight. I discussed it with the guys at the Dyno Shop in Santee. I was told neither would have an effect. I still find it a little difficult to believe, but have to think now that any effect is so minimal as to be a non-issue.
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Re: Tire size and Dyno results

Postby Sawfish on Wed May 20, 2015 6:42 pm

Thanks guys. Should be interesting. I am wondering where the car will classify when I am done :wink:
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