Help needed tyre question

[littlerick]

Hi all ive bought a set of porsche cup 3 alloy wheels for my s3 and im stuck with what size tyres to use due to it being 4wd i was thinking 205/40/17 for the fronts which are 7.5j and 215/40/17 for the rears which are 9.5j will these be ok with the wheel circumference? any help is better than no help please

 

[liquids3]

Best to type in google audi s3 tyre rolling radius sizes,there are websites that work it out for you!,should'nt be 3 mm difference i think,im running 215,35,19 front 235,35,19 rear!

 

[liquids3]

Thats 215,35,19 on a 8.5 and 235,35,19 on a 11j rear i went on the web page trc tyre radius calculation

 

[S3 Nattie]

I run 215/40/17 on the front and 225/45/17 on the rear. The smaller side wall will give better turn in and a lot less tyre wall flex.

215/40/17 gives a nice looking wheel also, bit of a stretch but not too much to effect performance. I wouldn't run 205/40/17 on a 7.5j or 215/40/17 on a 9.5j as I feel you would have too much of a stretch unless that's what your going for.

You could maybe run 215/40/17 on the front and possibly 225/45/17 on the rear due to the width of the wheel.