Tyre Width To Wheel Width Query

[Rob205 1]

Hi, bit of background first:

 

I'm making changes to my road use only 1.9 GTi one at a time and to experiment with the effect of wheel weights and handling I've fitted 6J/15" C5 steelies with the 195/50 15" Toyo T1S's that were on the original Speedlines. This was done as a cheap way of finding out whether fitting expensive Oz Ultras was going to be worthwhile.

 

Resulting findings are that the difference in steering weighting and better ride quality are amazing, I'd swear by lighter wheels now.

 

Anyway, enough waffle, please ask if you want to know more. I now want to swap the 195/50 15" Toyos back to 185/55 15" standard tyre size to further improve the ride, however the smallest Oz Ultraleggerra rim width I can find in 15" diameter is 6.5". As such can anyone help with the following:

 

Is a 6.5" rim width too wide for a 185 section tyre and if they do fit does anyone have an opinion on the steering/handling characteristics given that I imagine the tyre wall will be more inclined to slope inwards from the rim to the tread?

 

I've also now got a pair of 309 GTi driveshafts for fitting, will these make 6.5 inch rim widths with standard Pug offset protrude from the front arches too much?

 

Thanks.

[cybernck 402 1 Cars]

I've never had 185/55/15 on 6.5", so can't comment on that one. I have 195/50/15 on 6" and 7" though .

 

As for your other question, driveshafts can't affect the track width and it's not advisable to fit them anyway.

In case you meant 309 GTI wishbones, your track will be 1 cm wider per side, but mostly at the bottom,

as the wheels will get some negative camber. My 7x15" ET7 wheels protrude a bit at the front (as that's

nearly 25 mm wider over the track with standard wheels, per side), but you should be fine.

 

Hope this helps.

[Rob205 1]

I've never had 185/55/15 on 6.5", so can't comment on that one. I have 195/50/15 on 6" and 7" though .

 

As for your other question, driveshafts can't affect the track width and it's not advisable to fit them anyway.

In case you meant 309 GTI wishbones, your track will be 1 cm wider per side, but mostly at the bottom,

as the wheels will get some negative camber. My 7x15" ET7 wheels protrude a bit at the front (as that's

nearly 25 mm wider over the track with standard wheels, per side), but you should be fine.

 

Hope this helps.

 

Hi, yes your comments do help on both fronts. I should have said that I am fitting the longer 309 driveshafts in conjunction with 309 GTi wishbones.

I'd guess that the 6.5" wheels will protrude about 12mm less than yours per side depending on offsets so as you say should be fine.

 

Regarding the tyres, how did you find the fit of the 195/50/15's on the 7" rims? If they fitted ok then I'd expect 185's to fit on a 6.5" what with the wheel being about 12mm narrower and the tyre 10mm narrower than your setup.

 

Also, can you comment on any difference in steering feel/handling with the 195/50's on 7" rims as opposed to the 6" rims? I'd expect the 185/55 tyres to have the same characteristics as any you've found.

 

Many thanks for you help.

[cybernck 402 1 Cars]

Here's what 195/50/15 tyres look like on 7" wheels, a little bit stretched:

 

 

For a comparison, here are 185/55/15 tyres on 6" wheels:

 

 

As you can see, 185/55/15 have slightly more profile than 195/50/15, so they will sit just fine on 6.5" wheels.

 

Hope this helps .

[Paul_13 212 1 Cars]

Sorry for hijack but what width tyre do people run on SL434's?

[Baz 421]

195's.

 

185's will be fine on a 6.5" rim, it's only half an inch bigger than the standard wheel and might not even actually equate to that in real terms.

Edited February 13, 2012 by Baz

[Paul_13 212 1 Cars]

Cheers

Now answer your bloody texts

[niagra 3]

Mini owners fit 165s on 6 inch wheels so I reckon 185s should go on 6.5 ok.

 

Dario

[welshpug 1,666]

rather a difference in profile though, which makes quite a difference to how far the tyre can stretch, but indeed a 185 should be just fine on a 6.5" rim, have seen 195 45 on a 7" rim

Edited February 13, 2012 by welshpug

[johnnyboy666 195 1 Cars]

In my recent research into tyres, it seems that widths are more of a guidline as far as manufacturers are concerned. Some being the exact size e.g 185 and some being closer to the size above or below.

[Strictly_Derv 34]

I've stretched 165's on 6J's and they where fine

[TT205 42]

This is a great site for wheel/tyre info

http://www.carbibles.com/tyre_bible_pg4.html

[johnnyboy666 195 1 Cars]

tyres are remarkably stretchy

 

I've stretched 165's on 6J's and they where fine

 

ive had 215s on 10j

 

as to how well they perform at such stretches is a different matter all together

[ben_kilpatrick205 0]

Are the 1.9 Gti wheels 6.5J?

[welshpug 1,666]

no, 6".

[ben_kilpatrick205 0]

Ok thanks thought I read somewhere that they we're 6.5