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Anyone running 245 width tyres on a Cupra?

Kirky

Active Member
Apr 10, 2019
950
431
Does anyone run 245s on their Cupra? Is their any advantage/disadvantage running the larger width tyres?
 

SRGTD

Active Member
May 26, 2014
989
416
Can help with your first question, but a few points to consider below.

On a 245/35 tyre, the sidewall will be slightly higher than on a 235/35 tyre, so depending on brand of tyre, you might experience a little more flex in the sidewall under cornering. The larger overall rolling radius would also mean a very small speedo error reading. There’s likely to be a price difference between a 245/35 and 235/35 tyre, but the wider/higher tyre won’t necessarily be more expensive than the factory tyres.

Fitting different sized tyres to factory spec tyres is also considered as a modification for insurance purposes in the UK, so you’d need to inform your insurer.
 

Kirky

Active Member
Apr 10, 2019
950
431
Can help with your first question, but a few points to consider below.

On a 245/35 tyre, the sidewall will be slightly higher than on a 235/35 tyre, so depending on brand of tyre, you might experience a little more flex in the sidewall under cornering. The larger overall rolling radius would also mean a very small speedo error reading. There’s likely to be a price difference between a 245/35 and 235/35 tyre, but the wider/higher tyre won’t necessarily be more expensive than the factory tyres.

Fitting different sized tyres to factory spec tyres is also considered as a modification for insurance purposes in the UK, so you’d need to inform your insurer.
I thought the side wall would be the same being both 35, so this is good to know. I knew the tyre would be more bulbous in an 8j rim but didn't think there would be a sidewall size difference. Insurance isn't an issue as I'm going to change the rims in the near future hence asking if going 245 had any benefits, so I'd be informing the insurance anyway. Thanks for your help. Looks like I'm going to stick with 235s when I get my new rims going on what you've told me.
 

onkkel

Active Member
Jul 12, 2018
24
29
Finland
Tire profile is basically the side wall aspect ratio to the tire section width. On a 235/35 tire the side wall height, measured from the wheel rim to the outside of the tread, is 35% of the section width. In this case 82.25mm.

This said the difference between the tire sidewall height on a 235 and 245 tire, both with a 35 profile, is 3.5mm. Hope this helps!
 

Kirky

Active Member
Apr 10, 2019
950
431
Tire profile is basically the side wall aspect ratio to the tire section width. On a 235/35 tire the side wall height, measured from the wheel rim to the outside of the tread, is 35% of the section width. In this case 82.25mm.

This said the difference between the tire sidewall height on a 235 and 245 tire, both with a 35 profile, is 3.5mm. Hope this helps!
Thanks, this helps a lot as I never knew it was a ratio.
 

SRGTD

Active Member
May 26, 2014
989
416
Thanks, this helps a lot as I never knew it was a ratio.
Yes, it’s as @onkkel has explained. Sorry I didn’t explain this in my earlier post or when you subsequently queried it - I’m currently out of the UK and the internet connection is very flaky to put it mildly, so logging onto the forum is a challenge!
 
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g_berserk

Smartass in training
Oct 15, 2014
164
23
Monterrey, Mexico
I'm running 245/40/18 Sumitomo HTR Z3 on a 18x8 wheel.

Better traction, ride quality and peace of mind against potholes.

We're not talking about a quantum leap here, but noticeable enough to recommend if you're due changing the tyres. However, if I had to do it again, I would have gone with 35 profile instead.

 
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