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'99 max Wheel Off Set

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#1
ChrisA

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Previously, I was under the impression that 25mm was the max wheel off set for our cars, but recently I have seen a couple posts stating that 30mm is the limit. Which is correct?

Chris

 

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#2
davew

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There is no maximum wheel offset. The spec is based on track width. The track width spec was determined using a 25 mm wheel.

Dave

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#3
ChrisA

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There is no maximum wheel offset. The spec is based on track width. The track width spec was determined using a 25 mm wheel.

Dave

So by that I'm taking it that 15x7 w/25mm offset wheels are fine as long as I don't use spacers as well.

Chris

 

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#4
Johnny D

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So by that I'm taking it that 15x7 w/25mm offset wheels are fine as long as I don't use spacers as well.


Correct.
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#5
0100

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So +25mm on a 99+ is legal in SCCA SM???

Just want to make sure 100% before I place an order on some wheels.

#6
Tom Hampton

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So +25mm on a 99+ is legal in SCCA SM???

Just want to make sure 100% before I place an order on some wheels.


Yes.

I don't blame you for wanting to be extra sure, but note that the answers above were provided by: a) the person who wrote the rule, and one of the biggest SM builders in the country, B) a current '99 driver (and moderator on this site..but, you might not have known that part).


To clarify for ChrisA: the correct limiting term for Wheel Offset is MINIMUM (not max). Offset is the distance from the centerline of the wheel to the inside lug-face of the wheel. So, a smaller offset means that the wheel lug is closer to the centerline. A larger offset means the lug-face is closer to the outside rim. Smaller offsets push the wheel away from the body farther. This increases the track.

So, a 30mm offset can be used with a 5mm spacer to create a effective 25mm offset.

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#7
0100

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Doh didn't even see who posted that. lol

#8
Tom Hampton

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There is no maximum wheel offset. The spec is based on track width. The track width spec was determined using a 25 mm wheel.

Dave


Well, there "kinda" is:


The front track shall not exceed 1450 mm. The rear track shall not exceed 1475 mm. Aftermarket wheel studs, lug nuts, and wheel spacers are permitted. If spacers are used they shall be no greater than 13mm and equal per axle.

Which effectively means that 38mm is the largest offset that can be used...unless someone used something other than a 7" rim. But, that just makes my head hurt.


-tch
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#9
Johnny D

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Dave,
you may want to rewrite this on your site.
http://www.advanced-...55e8de7950cf001

J~
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We have a Winnah! - Won their 1st race... Congratulations! Beta-Tester - Assisted us with beta testing the website. Donor - Made PayPal donation Bona fide - A bonafide Spec Miata driver Novel Approach - When a paragraph simply won't do... Survive the 25, NASA Thunderhill - Survive the 25, NASA Thunderhill Instigator - Made a topic or post that inspired other Make it Rain - Made Paypal donation of $100+




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