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Model specific boards => Golf mk4 => Topic started by: Mr_Orange on 27 August 2012, 22:40

Title: 8.5 > 9.5 & rolling radius
Post by: Mr_Orange on 27 August 2012, 22:40

Wheel noob time.....  :embarrassed:
Someone talk to me about running staggered fitment.  Not mad keen on crazy stretch, so how do I get around running different widths and retain rolling radius? 

Very silly question time...... If rolling rad differs front to rear will it affect the traction control or owt like that?

Title: Re: 8.5 > 9.5 & rolling radius
Post by: dom on 27 August 2012, 23:08

Quote from: Mr_Orange on 27 August 2012, 22:40

Wheel noob time.....  :embarrassed:
Someone talk to me about running staggered fitment.  Not mad keen on crazy stretch, so how do I get around running different widths and retain rolling radius? 

Very silly question time...... If rolling rad differs front to rear will it affect the traction control or owt like that?

The difference will be minimal, nothing worth worrying about!

Title: Re: 8.5 > 9.5 & rolling radius
Post by: Chris. on 27 August 2012, 23:24

Rolling radius of 2 same diameter wheels with same tyres fitted to each axle will always be the same?

Title: Re: 8.5 > 9.5 & rolling radius
Post by: dom on 27 August 2012, 23:27

Quote from: Chris. on 27 August 2012, 23:24

Rolling radius of 2 same diameter wheels with same tyres fitted to each axle will always be the same?

He doesn't want stretch so will be having wider tyres on the rear, as the side wall of the tyre is a percentage of the width of it, the rolling radius will be marginally different front - rear.

For example the difference in rolling radius between 215/40/18 and 205/40/18 is 0.7mph at 60mph :wink:

Title: Re: 8.5 > 9.5 & rolling radius
Post by: Steve_PD on 28 August 2012, 09:30

Wheel info in the maintenance section has a link to a tyre size calculator where you enter the tyre size and will tell differences. Would post a link but that's hard work on a phone...

Title: Re: 8.5 > 9.5 & rolling radius
Post by: scarr89 on 28 August 2012, 09:34

Quote from: Chris. on 27 August 2012, 23:24

Rolling radius of 2 same diameter wheels with same tyres fitted to each axle will always be the same?

I thought this!

Obviously not!  :embarrassed:

Title: Re: 8.5 > 9.5 & rolling radius
Post by: Mr_Orange on 28 August 2012, 18:19

Yes mate. The middle number in a tyre size is wall height as percentage of the tyre width. I've run it all through a tyre and offset calculator to see what the differences are. Surprised to see such a change in speed etc!
Not mad keen on stretch as A) I'd want the tyre to stay on the rim and B) protrude to protect any nice new wheels I might get.

http://www.willtheyfit.com/index.php?width=205&aspect=55&diameter=16&wheelwidth=6.5&offset=42&width2=235&aspect2=40&diameter2=18&wheelwidth2=8.5&offset2=35&Submit=Submit

Title: Re: 8.5 > 9.5 & rolling radius
Post by: Steve_PD on 28 August 2012, 21:27

A 9.5 will with no stretch will require a 265 tyre. Have you seen the prices of 265's? more so I think it will scrub with a 265