Non-M sized tires on 224’s on an Si ?

[True-Blue]

Per thread title,

Popped the 224’s on today and currently thinking I’m going to stick with these over the 107’s....

Any issues with running Non-M sized tires?... so 225 40 18 & 255 35 18 want to fit new tires (but decent quality - Probably looking at Vredestein Ultrac Vorti’s) and Non-M sizes are definitely cheaper.

Many thanks

[Panta Rhei]

225/45 and 255/40 are m sized tyres and they will rub on non-M.
I had 224 with 225/40 and 255/35 on my previous 2006 3.0si roadster and they fit like a glove, not rubbing at all.
If I recall I bought Goodyear Eagle F1 Asymmetric 3/5 tyres. Cant remember 3 or 5.

[pauld]

I am having 255/35 18 fitted to my 224's tomorrow, to replace the 255/40's fitted 2 weeks ago.

I can confirm they rub even when you replace the lowered springs with standard height.

The front are new M sized and seem fine so they are not being replaced again!

I too went for Ultrac Vorti's. I have used them before and to me are a good balance between quality and cost.

What is strange is that the 255/40 ditch finder that were on when I purchased the car did not rub, so I replaced with he same not really giving it a second thought.

I'll report back tomorrow with regard to the rubbing and the new tyres!

[True-Blue]

Ok, thanks both.

Do they rub all the time, or occasionally over a bump type thing?

Just thinking about getting the car to a local tire place, literally swapped them over in the the garage yesterday, didn’t even move the car by more than a car length to reposition to do the second side.

I’d rather avoid getting the car completely up on axle stands with no wheels on if possible.

[pauld]

They catch when you go over a bump, but only very slightly.

I think that explains why the ditchfinders did not rub as the catching is minimal and the old tyres were worn down

The previous owner was like the chauffeur in Driving Miss Daisy so my not have really noticed it.

[mmm-five]

Don't forget that different manufacturers will have different tolerances for a specific tread width - and the shape of the sidewall/shoulder will also make a different to whether they rub or not.

I don't think there's currently an online resource to get specific & accurate tyre dimensions though, so it's trial & error.

You'll also have a bit of difference between suspension on cars (even the same models) as things wear.

[mr wilks]

The trick with 224 rears on non M is to fit a 245-40--18 rear.

[True-Blue]

The trick with 224 rears on non M is to fit a 245-40--18 rear.

Good to know

[pauld]

The trick with 224 rears on non M is to fit a 245-40--18 rear.

Are you sure as the 245/40 has a larger diameter than a 255/35, so will be more likely to catch?

There is a 10 mm difference in width, so 5mm on the outside. Is this sufficient to bring the tyre away from the edge of the wing

[mr wilks]

The trick with 224 rears on non M is to fit a 245-40--18 rear.

Are you sure as the 245/40 has a larger diameter than a 255/35, so will be more likely to catch?

There is a 10 mm difference in width, so 5mm on the outside. Is this sufficient to bring the tyre away from the edge of the wing

I'm meaning as a perfect option to retain as much comfort & wheel protection but without catching the inner arch then a 245 40 18 is the way to go if you are on style 224 ( Si - Se ) 255 35 is indeed a option but imo 245 40 is a better one .
The 255 40 18 "almost " gets away without rubbing & for many probably does do but a 245 just rolls the outer lip enough & has some already pointed out the difference between rub & no rub ca be l the difference in tyre brand or between partworns on 4mm & brand new on 8mm

[pauld]

The 255/35 Ultrac Vorti's have been fitted and a spirited test drive over perhaps 30 miles of the Peak District

They may have caught the wing once, but that was driving like a dick! It could also of been the bump stop.

So overall a good result.