Tyre profile / tyre choice - 987.2 Boxster S

[tallstevef]

Hi all,

Currently own a 987.2 Boxster S, this has some older Michelin PS2 N4 spec tyres fitted but they will soon need a change. The issue here is that on the 18" rims, the rear tyre size of 265/40 at the rear really limits choice, with mainly older tyre designs such as the PS2, F1 asymmetric 2 etc. The 235 choices at the front have all the more modern tyres, PS5, Contisport 7 etc.

Questions here are:

1. If sensible, could I change the profile of any new tyre to give me more choice? For instance, changing to a 265/35 at the rear gives as wide a selection as the fronts. But should I move up to a 45 profile, or down to a 35 profile? Is this ok?

2. Any thoughts on which of the more modern tyres to get, would have probably gone for Pilot 4S, but are the new 5 / latest Conti / latest F1 asymmetric better? Any experience from Boxster / Cayman folk?

Many thanks!

[Orangecurry]

I would ask this on a Cayster specific forum, as Pistonheads isn't as technical as it used to be.

But....

tallstevef said:

1. If sensible, could I change the profile of any new tyre to give me more choice? For instance, changing to a 265/35 at the rear gives as wide a selection as the fronts. But should I move up to a 45 profile, or down to a 35 profile? Is this ok?

It is always 'ok' to vary tyre dimensions, as long as it isn't by much. If you look at the manufacturer specified options for the different wheel sizes, you will find a certainly-ok range of overall tyre size that you can work within, and usually you can stray a few percent outside of that range. Use something like this to input on one side what Porsche fitted, and compare against tyre-sizes that are readily available today on the other side.

https://www.wheel-size.com/calc/

tallstevef said:

2. Any thoughts on which of the more modern tyres to get, would have probably gone for Pilot 4S, but are the new 5 / latest Conti / latest F1 asymmetric better? Any experience from Boxster / Cayman folk?

Look here to find proper unbiased technical comparative testing, either by Jon himself or by the many mostly European independent testing industry icons.

https://www.tyrereviews.com/

Edited by Orangecurry on Saturday 17th June 09:52

[ricof]

Hi, different car (987.1) and difference wheel size (17") but I had a very similar conundrum recently. Standard tyres sizes were 205/55 and 235/50 and was pretty much limited to Pilot Sport 2 or Eagle F1 Asymmetric 1, which are both older tyre tech now.

I decided to go for Eagle F1 Asymmetric 6 in 205/50 and 245/45. It's a tiny tiny change in overall diameter and ride height and something like a 2% increase in indicated road speed but small sacrifices for much more modern tyres. Have done about 1000 miles on them so far and they do feel a lot better.

I had four tyres fully fitted etc for £550 through Asda tyres and there was an offer for £40 Asda voucher cashback too. So four brand new premium tyres fitted for little more than £500 which in today's climate I think is pretty decent.

[ATM]

tallstevef said:

Hi all,

Currently own a 987.2 Boxster S, this has some older Michelin PS2 N4 spec tyres fitted but they will soon need a change. The issue here is that on the 18" rims, the rear tyre size of 265/40 at the rear really limits choice, with mainly older tyre designs such as the PS2, F1 asymmetric 2 etc. The 235 choices at the front have all the more modern tyres, PS5, Contisport 7 etc.

Questions here are:

1. If sensible, could I change the profile of any new tyre to give me more choice? For instance, changing to a 265/35 at the rear gives as wide a selection as the fronts. But should I move up to a 45 profile, or down to a 35 profile? Is this ok?

2. Any thoughts on which of the more modern tyres to get, would have probably gone for Pilot 4S, but are the new 5 / latest Conti / latest F1 asymmetric better? Any experience from Boxster / Cayman folk?

Many thanks!

I've done exactly this on my 981 but for different reasons. Once you get away from factory sizing you get so many more options. If you really want performance then you could look here - link below. This is the 981 platform but gives you an idea. It seems simpler to just change the width by 10 front and back and go down in profile by 5 if really necessary. I wanted thinner tyres with softer side walls so I went the other way. Just try to do a similar change to front and back to even it out if poss. But the car will drive fine as in the electronics and nanny systems so dont worry about that.

I guess your immediate options are

245 40 18 / 275 40 18
225 40 18 / 255 40 18

Or keep your 235 40 fronts and just change the rears to 255 or 275

For a road car I'd recommend thinner is better but thats not a popular opinion on PH

https://support.apexraceparts.com/hc/en-us/article...