Track tyres for my Boxster GTS

[AndyKerr]

I'm looking at the possibility of getting a set of wheels and tyres specifically for track work. I've had a fascinating discussion on the subject with Nick Pike of this parish, but would like to poll the register for it's experiences.

The car came with Eagle F1's, and while they are a very good road tyre (if a little noisy on poor surfaces) I don't feel they quite do the car justice on track days.

While researching the field for alternatives, an issue has come to light:

Of the obvious alternatives (P-zero Corsa, Pilot Sport Cup 2 and Pilot Supersport being the ones I've considered), so far as I can tell none is availabe to fit my car (235/35/R20 and 265/35/R20). The nearest I can find is 235/40/R19 and 265/40/R19 in the Pilot Sport Cup 2 - and then only on the Michelin website (none of the usual outlets seem to stock them and the Solihull dealership was unable to uncover any sources). The 19" rims will apparently fit over the ceramic brakes without any problems and in any case are definitely available as an option in the car's onboard wheel selection menu.) As far as I know Cup 2s don't come with an N rating because of their intended function; and although the Supersports do I think, I've had no luck sourcing any that will fit either rim size.

Does anybody have any suggestions or personal experiences that might help in this regard? I'm hoping for responses in the general vicinity of alternatives, suitability and possible warranty issues.

 

[Terry]

I can't help with the sizes for your Boxster but can confirm that the Cup 2s fitted to Porsches as standard (GT4 for example) are N rated.

 

[Gordon Attar]

Have a look in your owners manual as you have several wheel and tyre sizes you can go for.

Alternatively if your not a very experienced track enthausist then standard tyres will be more than good enough for your first few experiences. Getting to the limits of your standard tyres helps on the road. Sounds like youve been on a track day with your eagles might be a good idea to wear them out on another and try some other tyres.

PS be careful with those gravel traps they are ceramic brake killers.

 

[MrDemon]

geo is the 1st thing you will need other wise your fronts will be toast in 3 laps if you can pedal a car ok.
2nd some motul 660, and GT3 brake ducts to help the PCCB cool as heat kills them, and at £4k a disk you don't want that.

981 tyres are a pitter size, you could try super sports fronts non N spec, and a BMW logo rears , and would be my choice and correct size.

Terry GT4 sizes are a no go they are 245/295 and a bit large for the GTS

 

[AndyKerr]

Have a look in your owners manual as you have several wheel and tyre sizes you can go for.

Alternatively if your not a very experienced track enthausist then standard tyres will be more than good enough for your first few experiences. Getting to the limits of your standard tyres helps on the road. Sounds like youve been on a track day with your eagles might be a good idea to wear them out on another and try some other tyres.

PS be careful with those gravel traps they are ceramic brake killers.

Thanks for the response. I've been doing 3 or 4 track days a year for about the last 5 or 6 years in 4 different versions of the Boxster. Hopefully that answers your second point (with due apologies if that wasn't clear already). It is true that I don't habitually chase lap times, but I do get the feeling that the car can do more in the corners than seems to be available from the Eagles.

There's a wheel/tyre submenu in the 981 TPM section which, as I said earlier, lists 19" rims. Unfortunately the owner's manual wasn't as helpful as I'd hoped in this regard since although it shows 19" rims as an available option for the GTS it provides no information as to tyre choice (although in fairness it does list 40-section tyres on 19" rims for the S). Hence this thread.

I think it's been said already, but the GT4 tyres are a fairly specific size for that model, and won't fit the Boxster. I'm pretty sure that the tyres I need don't come in a N rated version.

At this point I'm looking at Cup 2s on 19" rims. (The Supersports would probably be a slightly better choice for my needs but they don't seem to be made in any sizes that fit the GTS.) I have a query as to why this option isn't mentioned in the manual though - perhaps it's something to do with the active suspension (which rides 10mm lower than the standard suspension).

 

[AndyKerr]

geo is the 1st thing you will need other wise your fronts will be toast in 3 laps if you can pedal a car ok.
2nd some motul 660, and GT3 brake ducts to help the PCCB cool as heat kills them, and at £4k a disk you don't want that.

I doubt I'll be going fast enough for any of that to be an issue. Interesting thought though...

981 tyres are a pitter size, you could try super sports fronts non N spec, and a BMW logo rears , and would be my choice and correct size.

That might be a plan. I'll look into it. Thanks.

 

[ralphmusic]

A couple of thoughts:

If you are going to run track oriented tyres you might want to run more camber to better use the tyre

Think about closing the wheel width gap between front and rear so you can run 245 (v 235) & 265 to help reduce understeer

There are no non-N rated Supersports, but there are Mercedes, BMW and Ferrari specific versions. I am on 20" 245/295 and use the non-specific manufacturer version. The last set still have 5/6 mm tread after 12 Trackdays and 10k total miles in 2016, but they lose their youth with repeated heat cycles so get replaced each year.

 

[AndyKerr]

A couple of thoughts:

If you are going to run track oriented tyres you might want to run more camber to better use the tyre

Think about closing the wheel width gap between front and rear so you can run 245 (v 235) & 265 to help reduce understeer

There are no non-N rated Supersports, but there are Mercedes, BMW and Ferrari specific versions. I am on 20" 245/295 and use the non-specific manufacturer version. The last set still have 5/6 mm tread after 12 Trackdays and 10k total miles in 2016, but they lose their youth with repeated heat cycles so get replaced each year.

Will 245s fit the wheel arch on a Boxster without snagging? Or are you using a spacer? Also I don't have the skills - much less the equipment - to adjust camber. Will the dealership do it or should I take it to an independent?

 

[ralphmusic]

Will 245s fit the wheel arch on a Boxster without snagging? Or are you using a spacer? Also I don't have the skills - much less the equipment - to adjust camber. Will the dealership do it or should I take it to an independent?

I am running 20" 245/35 tyres on 8.5" rims with 45 offset (ET45) on my 981S Cayman with no spacers and no fitting issues.

Who does alignment best?
Some Porsche Centres do a good job but they'll ask what settings you want.
Some Independents do a good job but they'll often ask what settings you want.

Where are you based?

 

[AndyKerr]

Will 245s fit the wheel arch on a Boxster without snagging? Or are you using a spacer? Also I don't have the skills - much less the equipment - to adjust camber. Will the dealership do it or should I take it to an independent?

I am running 20" 245/35 tyres on 8.5" rims with 45 offset (ET45) on my 981S Cayman with no spacers and no fitting issues.

Who does alignment best?
Some Porsche Centres do a good job but they'll ask what settings you want.
Some Independents do a good job but they'll often ask what settings you want.

Where are you based?

I live in Redditch and bought the car from Porsche Centre Solihull (which is a Premier dealership and from whom I've always had exemplary service). What sort of adjustment are we talking about?

Actually it's just occurred to me that it might be worth mentioning the PTV I have on the car...

 

[ralphmusic]

Andy,

May I suggest you call Chris Franklin at Centre Gravity in Atherstone (+44 1827 718800) and see what he thinks - early morning c08:15 is often best. They are generally accepted to be amongst the best on alignment and I am sure Chris will give you useful comments. I have no direct interest in CG but I travel up from Devon to have him do his magic on my rather non-standard car.

I suggest you do not really want to go down the full set-up route with Chris as it can get expensive. He can probably suggest a set up (camber/caster/toe) that you could achieve with standard suspension components to meet your usage needs.

Ralph

 

[AndyKerr]

Thanks for that Ralph. Much appreciated. As you suggest I don't consider myself hardcore where track activity is concerned (and when all's said it's also our one and only family car); but I do like to go fast, and I honestly think the current tyres are not doing the car justice.

I'll give him a call.

 

[MrDemon]

If I were to own 981 boxster I would fit the tcp sus kit and those super sports in 20" the rears as I say in BMW logo mode.

 

[ian harvey]

Toyo 888s are a really good track tyre used by many a Porsche track driver. I do a similar number of trackdays to you and really like them. They grip really 'hard' once warmed, don't 'go off' too badly when hot unless you are very committed and are fine in damp or wet conditions. Last quite well, too. Standing water is a problem, however. I whip them straight off again once I'm back home as they are a noisy, harsh road tyre. Not N rated but who'd have to know?

 

[AndyKerr]

Toyo 888s are a really good track tyre used by many a Porsche track driver. I do a similar number of trackdays to you and really like them. They grip really 'hard' once warmed, don't 'go off' too badly when hot unless you are very committed and are fine in damp or wet conditions. Last quite well, too. Standing water is a problem, however. I whip them straight off again once I'm back home as they are a noisy, harsh road tyre. Not N rated but who'd have to know?

Thanks for the suggestion. Unfortunately they don't seem to be available for the Boxster's rims.

 

[geoff lane]

Andy
Don't know if its of any help but you can get Cup 2's 265/35/20 although you don't seem to be able to get 235/35/20 you can get 245/35/20 and both can be N rated.
Try looking on Tyre Leader web site. I have used them in the past and always been okay, just try and check the age of the tyres before ordering as they come from all over Europe. They seem to be able to supply where in the past I have struggled.

Geoff

 

[AndyKerr]

Thanks for all the suggestions guys. I now seem to have a couple of possibilities to explore. I'll know more once I've spoken to Ralph's contact in Warwickshire.

 

[AndyKerr]

Andy
Don't know if its of any help but you can get Cup 2's 265/35/20 although you don't seem to be able to get 235/35/20 you can get 245/35/20 and both can be N rated.
Try looking on Tyre Leader web site. I have used them in the past and always been okay, just try and check the age of the tyres before ordering as they come from all over Europe. They seem to be able to supply where in the past I have struggled.

Geoff

Thanks for that. I'll check it out now.

 

[spyderman]

Don't suppose you can get Toyo R888Rs in 19s?

 

[AndyKerr]

Don't suppose you can get Toyo R888Rs in 19s?

Not in the configuration I'd need unfortunately.