Will a 6% increase in rolling circumference make a huge diff

Wheels, Suspension, Brakes & Tyres questions and answers

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Adam_NAclubman
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Postby Adam_NAclubman » Wed Jul 19, 2006 12:33 pm

:oops: I forgot I was going from 14 inch to 15 inch :lol:

185/60/14 to 195/60/14 would see an increase in diameter of 12mm, so yeah, it would be about an inch and a half going to 195/60/15, though maybe a tad less depending on whether a 195 stretches much to get onto a 7 inch rim.

Maybe I'll wait an extra couple of weeks and get a full set of 195/50/15's instead

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Postby Adam_NAclubman » Tue Aug 22, 2006 8:49 pm

Went with 195/50/15 A539's. Should be a 3% decrease in rolling circumfrence but I can live with that

http://s47.photobucket.com/albums/f152/ ... an/MX5/P1/

Ended up that the rh rear was scrubbing on bumps and lh corners in the hills so we rolled the guard with a footlong piece of a tree branch on the side of the road :lol: Barely scrubbed after, only on BIG bumps, and the guard was rolled really smoothly with no damage to any of the paint. Pity we redid it with a metal pipe after we got back home

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JBT
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Postby JBT » Tue Aug 22, 2006 9:20 pm

195/50/15\" is the correct size.
Image

Adam_NAclubman
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Postby Adam_NAclubman » Wed Aug 23, 2006 1:41 am

If standard tyre is a 185/65/14, a 195/50/15 has a 3.37% smaller rolling circumfrence. A 195/55/15 however only has a 0.1% smaller circumfrence

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Postby Richee » Wed Aug 23, 2006 7:41 am

I thought the standard size was 185/60/14 with 195/50/15 as JBT says being the appropriate upgrade

EDIT : I hope so because Mr Startrackexpress is delivering my NB8A wheels today :D :D
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Boags
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Postby Boags » Wed Aug 23, 2006 8:56 am

Yep, 185/60/14 is standard.
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Adam_NAclubman
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Postby Adam_NAclubman » Wed Aug 23, 2006 12:34 pm

In that case, 195/50 is fine. And the bloke at the tyre shop is a git for selling me 185/65's because \"thats the standard size\"

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Re:

Postby Richee » Wed Aug 23, 2006 1:12 pm

Adam_NAclubman wrote:And the bloke at the tyre shop is a git for selling me 185/65's because "thats the standard size"


Correct :mrgreen: :mrgreen:
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Coming - Jayco Eagle wind up camper - woo hoo
Ex cars 2007 NC LE Radiant Ebony, 1990 Eunos Neo Green LE


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