S1 Evora tyre width question - 225 vs 235

[electro_boy]

I have a S1 Evora with the 18/19 wheels, am currently running Michelin Super Sport (SS) used to run the Pilot Sport 4 (PS4), I found the SS can cope a bit better with high temps during the handful of trackways I do and are a better balance of compromise for my circumstances.  

Current tyres are getting low on tread and will need replacing soon.  I was just going to get another set of SS but I have realised there are some retailers in UK now offering the Pilot Sport 4 S in 235/40/R18 size.   I'm pretty sure I couldn't find any PS4S in vaguely the correct size last time?

Reviews all state the PS4S is the better tyre, higher performance and less compromises so ideally would the tyre I'd prefer to get.  The Lotus recommended size is 225/40/R18 on the front will there be much difference in the handling or feel of the car using a 235/40/R18 tyre instead? 

Any got experience running a wider tyre?

[Bibs]

I asked Nick Adams about tyres sizes once and he said that +/- 10mm should make no discernible difference to the car at all. Nick was Chief Engineer, Prototype Vehicle Build & Development at Lotus at the time. 

[TdM]

I've run wider tyres on cars in the past like that, it was fine no problem at all.

The only issue I've seen is if you go smaller and it looks terrible as it has a 'pinched' look

[Jmanji]

Assuming you put the 235/40/18 on The front  what rear tyre size Is correct or best  

255/35/19

275/35/19 

[jep]

Modern cars are ridiculously over-tyred. For road use sports car , skinnier the better (within reason). Designers love big tyres for looks but in reality it makes driving cars less fun.

I take your point re your favourite tyre and if a small increase is the compromise, so be it. 

Justin 

[electro_boy]

Thanks for the info Bibs you've made my day!  I think that opens me up to Conti's range of high performance tyre too so may have to start reading reviews again!

@Jmanji, I'm going for the 255/35/19 to keep close to standard as possible.  I think a 275 would be too much, I would maybe go to a 265 if a 255 was not available.

[Peters4]

About the rear tires, I noticed that Michelin also provides the PS4 with a bit higher ratio: 275/40/19.

I think this would fill the rear wheel arches a bit more but will it work? Or will for example the ABS give issues because of different front/rear wheel speeds?

[electro_boy]

Comparing the 275/40/19 with the standard size of 255/35/19 thats a whopping 6.5% change in diameter I think general rule of thumb is to stick to around 1.5% difference.

[Julian73]

On 06/07/2020 at 05:59, electro_boy said:

Thanks for the info Bibs you've made my day!  I think that opens me up to Conti's range of high performance tyre too so may have to start reading reviews again!

@Jmanji, I'm going for the 255/35/19 to keep close to standard as possible.  I think a 275 would be too much, I would maybe go to a 265 if a 255 was not available.

S1 Evora's are VERY sensitive to the rotation between front and rear rolling diameter.  Get it off from stock by a few percent and you will find that the traction control system will shut the car down and place in limp mode, i.e. max rpm about 4,000.  The S2's (4xx series) may be less sensitive? I don't know, but we are not receiving complaints feed back and I'm sure someones tried wild tires sizes.

[Peters4]

At this moment, my rears are 275/30/19 (as fitted by the local Lotus dealer on my 2010 S1 NA), no problems at all with TC or ABS.

 

[electro_boy]

Use the following tyre size calculator to see what the difference in the size will be:  https://tiresize.com/calculator/

As far as I understand, 255/35/19 is standard fit for a S1 Evora,  275/30/19 is -1.9% difference in diameter, which is quite a lot.  A return to the standard size will make the car handle like it was intended and be slightly bigger (I'm assuming you are running standard sized fronts 225/40/18).  If you want bigger still to fill the arches more 265/35/19 is +1.2% and within an allowable deviation so should feel fine.

If thats still not big enough your options are either move to the 19/20 wheel set sizes that were optional extras for the S1 but then that starts to get expensive as you'll need 4 new wheels and tyres.

 

[Bravo73]

2 hours ago, Julian73 said:

S1 Evora's are VERY sensitive to the rotation between front and rear rolling diameter.  Get it off from stock by a few percent and you will find that the traction control system will shut the car down and place in limp mode, i.e. max rpm about 4,000.

I’m not so sure about that. 

My road wheels on my S are 19/20” with OEM Ev400 sized tyres. My track wheels are 18/18” with the ‘standard’ Lotus Cup Avon ZZRs on them. I have never had any ABS or traction issues swapping between the 2 sets.