Do they make much difference running this size on a vRS? 225 is standard size. Fronts will be due in 2000 miles or so, so was thinking lighter wheels and Michelin's at the same time. Wondering if the extra width would be worth it.

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Do they make much difference running this size on a vRS? 225 is standard size. Fronts will be due in 2000 miles or so, so was thinking lighter wheels and Michelin's at the same time. Wondering if the extra width would be worth it.

For most brands of tyre the minimum rim width for a 235/40r18 is 8".  Most vRS came ex-factory with 7.5" rims.

 

If you have 8" rims then the bigger tyre fills the guard a bit better and provides a fraction more pothole protection.

Thanks. I have mk3 Octy rims on atm but looking at either Neuspeed to Speedlines that are 18x8.

Logically a wider tyre should be more grip, just wanted more info on what it feels like in the real world.

Logically a wider tyre should be more grip, just wanted more info on what it feels like in the real world.

You'll get more ultimate grip but turn-in will be a fraction lazier because of the higher sidewall.  You can compensate for most of this by running slightly higher pressure.  Of course, this is if you are driving 7/10ths plus.  If you are just tootling about like a law abiding citizen then I doubt you'd notice any negatives.

 

Personally, I think the 225/40r18 looks under-done at 25.1", narrow & (especially) too small in diameter.  The 235/40r18 adds that fraction more (25.4" diameter) and also makes the ride less harsh & the speedometer more accurate. 

 

I'm not sure about the UK but down here the bigger tyre is about 30% cheaper as it's fitted to a lot of cars.