Thoughts on fitting smaller tyres

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Jules
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Thoughts on fitting smaller tyres

Post by Jules » Fri Aug 07, 2009 11:40 am

Out of curiosity,what do you think would be the downside of fitting smaller tyres,The alloys i am running at the minute are fitted with 265/30/19.
Ive just had a look at other options of wheels and have seen a few sets that are 8.5 inch wide.As these are narrower what would it be like with say 235/35/19s. Apart from less rubber on the ground any other downsides.
Also what width tyre could i got op to with a 8.5 inch alloy.

Thanks in advance

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RE: Thoughts on fitting smaller tyres

Post by gareth215 » Fri Aug 07, 2009 12:15 pm

On the plus side it would be a lighter wheel tyre combo so less unsprung weight and therefore improvement in ride/handling.

Also a bit less tramlining from the narrower tyres.

The standard 18.8.5 tyres uses 255 profile.
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RE: Thoughts on fitting smaller tyres

Post by RS4_fin » Fri Aug 07, 2009 12:32 pm

18-inch is my preference, so no downside going from 19 :)
On a narrower tyre in regards to the rim, 225/40/18 is about the minimum for standard one - and it will look funny. Have not tried booting with this kind of setup on track so cannot tell how it would behave under the car.
As obvious, 255 is good for 8.5.

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Post by Jules » Fri Aug 07, 2009 12:34 pm

Sorry,not explained to well,i'm sticking with a 19" alloy,just fills the arches better

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Post by N11LS_J » Fri Aug 07, 2009 5:23 pm

Jules, you need to keep the rolling radius the same, for example, if you go narrower, you would have to increase profile i.e 40/45mm...

If you want to keep low profile with narrower width, the only downside I can see really is that your speedo will be out quite a bit, there are tyre calculators on the web to help you toy with different sizes, have a play with sizes on here...

http://www.tyresave.co.uk/tyresize.html

maybe sticking to 255 as a minimum is best?

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Post by Virdee Autos » Fri Aug 07, 2009 11:06 pm

On a 8.5J I certainly wouldn't go for a tyre less than 245, especially on a car like the RS.

All IMO of course!
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Post by RS4_fin » Tue Aug 11, 2009 8:51 am

Virdee Autos wrote:On a 8.5J I certainly wouldn't go for a tyre less than 245, especially on a car like the RS.

All IMO of course!
Agree!

Forgot one obvious downside; going for a narrower tyre means "faster" or "lighter" steering feel, depending on how much was the difference. Less resistance you see... Like it more steady, myself.

Would keep the circumference about the same too.

Though the 19-inch "hint" was taken, you can "play" with the visual outlook of filling the arches to some extent with ride height.

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Post by missmouse » Thu Aug 13, 2009 8:08 am

isnt it illegal to fit smaller tyres than the oem?
Im sure it used to be called undertyreing or something?

maybe they changed the law when those skinny spacesavers came out.

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