Exige V6 - Rear tyres

[Guido]

Rear tyres will need changing fairly soon....................

My Exige is currently fitted with 265/35R18 rears.  The Sport 380/410/430 are fitted with 285/30R18.  Would there be any benefit in going with a bigger profile rear tyre?  I'm just looking at some options.  Cup2's are proving difficult to find.

[Oakman]

Hello Guy,

I don't know how much advice I can give you regarding what's totally suited to your Exige.  Barring the reality that all motor manufactures tend to specify an ideally sized tyre and compound spec to suit the particular vehicle. 

In our case with Lotus being amongst, if not the best road car chassis / suspension designer, they will take more time to make sure the individual models have tyres that suit them best for all requirements.  One can see the higher power cars potentially needing wider tyres to increase all round grip further.  Sometimes going wider / larger doesn't always mean an improvement IE you have more grip than you need and a wider larger mass to rotate - I'm sure the track specialists will know more about that. 

An example being that Caterham 7's look good on 15" to 17" wheels, but all the track boys and racers run them on 13" wheels/tyres, it reduces the weight and the slightly taller tyres help them with suspension compliance. 

It's fairly well known that it's a good thing on an S1 Elise to go to the 111S rear tyre widths to offset some of the on limit twitchiness they were known for.  On the early S2 Elise Lotus altered the suspension  geometry and made them understeer more for greater built in road safety and lessen the on limit snap oversteer.  To aid this they fitted narrower front tyres than the S1 had, a common mod or upgrade for the more adventuress S2 owner was to fit the wider S1 sized tyre to neutralise the inherent understeer. 

On the classics, many people fitted the slightly wider Elan +2 tyres on an Elan - up by only 10mm to 165 x 13 - it doesn't improve the handling on them.

To summarise - I guess only the owners of similar 350 Exige like yours can give a better idea.  It no doubt will be that us mere mortals can't tell and you'd have to be a Track God to be perceive the difference 😁

Regards,

Paul

[MG4Lotus]

I've seen mentioned in another place that changing the aspect ratio will change the circumference and may have an effect on the software that controls traction. If the rate the rear wheels are turning comparative to the rate the front wheels are turning, it may think the wheels are skidding, it may also throw up some errors.

Are the fronts on the Sport 380/410/430 also a different size?

You might want to see if you can borrow some of the rears and try them out, see how they go, before forking for them.

[Guido]

I would say the rolling radius would remain the same as the profile of the tyre is small 35 to 30. The only change would be with width of the tyre.
The reason I ask is someone has a full set of part worn Cup2 (6.5mm left all round) for £400 all in.

Edited April 4 by Guido

[LotusDave]

Sorry I can't help but weigh in on a tyre question, i'm a bit of a tyre nerd! So I will try my best to not write a book on here!

Long story short, it all depends on what you want from the car. The first thing I would say is think about what you do with the car, do you track it? Do you drive it hard on the road or do you drive more leisurely?

Be honest with yourself, as that will dictate what is actually right for you (not what others say is right for you!)

Me personally for my 'road' set up, I ditched the horrible semi-slick tyres and went with UHP road tyres and it made life, driving the car on the road, exponentially better in every way.

On the subject of wider tyres, it's all about compromise. Typically a wider rear tyre will cause your car to turn/rotate less in corners, it also will increase your fuel consumption, and road noise, it will add unsprung mass on the axle, and it will give you less lateral (cornering) traction, if you do not in turn, increase the wheel width. Also takes longer to get them warmed up and usually costs more to buy, as well. Those are the cons.

The pros are more contact patch which will give you more rolling traction, meaning better braking and acceleration (in a straight line), which on the rear will mean more stability under braking and better thermal management (for when you are driving really hard) the tyres won't go 'off' so quickly on track.

That's a high level synopsis, me personally, i'd stick to the stock 265 width, and just get the best tyre you can in that size. Without the additional tweeks that the 380/410/430 have, you will only be reducing the capability/balance of your car.

Tyrereviews.co.uk is a great resource to see other peoples experiences with their tyres and different comparisons in segments. For your car I imagine you will be looking at the UUHP tyre segment. If you have any questions, feel free to message me.

[Guido]

1 hour ago, LotusDave said:

Me personally for my 'road' set up, I ditched the horrible semi-slick tyres and went with UHP road tyres and it made life, driving the car on the road, exponentially better in every way.

 

For me, it's 'spirited' road use.  I do like to push on when I can so it's certainly not a leisurely drive when I get out and about.

I like the Cup2's as I've got used to how they work for me.  For sure, wet grip is compromised but I don't push hard in the wet so I don't really notice it.  What make did you end up fitting to yours in the end?  There may well be a better road tyre for me (Mich PS5?)

[LotusDave]

I went with Goodyear Eagle F1 A6, which is a UHP tyre, which gives better balance in the dry and wet with more comfort and lower noise, which was more of a priority for me. It also doubles as my 'wet set' on track.

With the higher HP on yours and if you like to push on in it on the road, I imagine you'd prefer more of a UUHP+ tyre. The Cup 2 is a Track/Competition tyre, and where may be great on track, does compromise a lot on road to get that maximised dry grip.

If that's not a problem for you and they are working for you, just get some replacements. However FYI, the Cup2 Connect is the replacement tyre for the older Cup2.
Tyre reviews: "This tyre replaced the Michelin Pilot Sport Cup Plus and this tyre has been replaced by the Michelin Pilot Sport Cup 2 Connect."
MichCUP2Connect @ £313 per tyre

If you wanted to go more extreme with the dry grip attributes, you could look at some alternatives like;
The Pirelli P Zero Trofeo R @ £365 per tyre
or the Bridgestone Potenza Race @ £349 per tyre
or the Nankang CR-S Tyre @ £330 per tyre

So much choice these days