GT4 Tyres

[ian harvey]

I've just inspected the tyres on my GT4 as they are close to being worn out and need to be replaced before long. I'm surprised to see that the current tyres, the ones that it left the factory with, are not N/NO rated!

I guess that this is something to do with the shortages being experienced at launch and that I'm not alone. NO rated ones are currently available. I would consider the PS 4S but they aren't available on the rear in N/NO and even though Porsche supplied me with non-N tyres I doubt they'd approve me doing the same.

Any thoughts on the N rating in this situation and particularly on the 4Ss. In my experience the wear on the Cup 2s is quite good all considered, how would the 4Ss cope with a few track-days in the hands of a mere mortal?

Ian

 

[ralphmusic]

No experience of 4S but I ran MPSS on my car below doing maybe 10 track days and 7k miles overall pa and a set lasted a year, although I tend to change tyres before they get down to 3mm tread. I changed to Cup2 tyres and was much faster round all circuits and am just changing a set of these after a year with 7 track days with 3mm still left because they have had enough heat cycles. Cup2s seem to be a good day to day tyre for "sporty" driving although they don't like standing water or cold temperatures.

 

[ian harvey]

Thanks Ralph

 

[Ray]

I've just inspected the tyres on my GT4 as they are close to being worn out and need to be replaced before long. I'm surprised to see that the current tyres, the ones that it left the factory with, are not N/NO rated!

I guess that this is something to do with the shortages being experienced at launch and that I'm not alone. NO rated ones are currently available. I would consider the PS 4S but they aren't available on the rear in N/NO and even though Porsche supplied me with non-N tyres I doubt they'd approve me doing the same.

Any thoughts on the N rating in this situation and particularly on the 4Ss. In my experience the wear on the Cup 2s is quite good all considered, how would the 4Ss cope with a few track-days in the hands of a mere mortal?

Ian

https://www.youtube.com/watch?v=ovwopvZLuNc&t=348s

Ray

 

[Fletch88]

just so happens I was at Porsche dealership today and got to talking about tyres

apparently you will be risking making your warranty invalid if the tyres are not N rated, as Porsche have spent a lot of time and effort in getting N rated tyres in production

I would suggest investigating

this

hope it helps

 

[ralphmusic]

https://www.youtube.com/watch?v=ovwopvZLuNc&t=348s

Ray

Pretty fair view. I would say rear traction on BMWs is probably much poorer than Porsche. Also compounds and sidewall construction can be different on the "same" tyre homologated for different car manufacturers so maybe a small chance BMW's 4S v Cup2 might be different to Porsche's?

 

[ian harvey]

Thanks guys. I'll probably stick with the Cup 2s as I've been happy enough with them so far and I've tried different tyres in the past and not been happy with them so it's not worth the risk. Sounds like the 4Ss may suffer heavy wear on a hot track day although i wouldn't mind a set for the RS day on Friday!

 

[Brian_Innes]

I'll be track testing the PS4S N0 on my 718 CS at Knockhill at the end of March. My impressions will be posted on my 982 718 Cayman S PDK thread.

As previously stated, the PS4S N0 is currently only available in sizes for the 718.

I would recommend you stick with the Cup 2's on your GT4.

Brian

 

[ian harvey]

Brian, you're right, I'll stick with the Cup 2s. I know Porsche would 'have' me for not fitting the NO tyres plus I like them any way it's just the rave reviews of the 4S that got me thinking, especially this time of year and the fact that I use the car on the road 95% of the time.

I read somewhere, Michelin's web-site I think, that 80% of the 4Ss tread is optimised for wet weather and only the outer 20% was 'track-hard' which makes me wonder how robust they may (not) be on a hot, dry track.

Cup 2s it is, then. Thanks all.

 

[delboy225]

I'll be track testing the PS4S N0 on my 718 CS at Knockhill at the end of March. My impressions will be posted on my 982 718 Cayman S PDK thread.

As previously stated, the PS4S N0 is currently only available in sizes for the 718.

I would recommend you stick with the Cup 2's on your GT4.

Brian

when you say only available in sizes for the 718, will not the 20" fit the 981, I know they have a slightly higher load rating (99y & 92y compared with 95y & 88y) does that matter, is it a warranty problem?

also are the Pirelli p zero sc N1 better than the N0. (what does the sc mean?)

sorry it is a tyre question

 

[tcreswick]

I read somewhere, Michelin's web-site I think, that 80% of the 4Ss tread is optimised for wet weather and only the outer 20% was 'track-hard' which makes me wonder how robust they may (not) be on a hot, dry track.

Fair comment, although I've had these on my 987 S for about 9 months now and I think every track day has been wet or partially wet, so it's probably not a ridiculous compromise

I think out of 5 track days on these tyres I've had one dry session so far. They were amazing, but looking forward to pressing them a bit harder this summer if I ever get a dry day.

Luckily I quite like wet days...

 

[Brian_Innes]

/quote]

when you say only available in sizes for the 718, will not the 20" fit the 981, I know they have a slightly higher load rating (99y & 92y compared with 95y & 88y) does that matter, is it a warranty problem?

also are the Pirelli p zero sc N1 better than the N0. (what does the sc mean?)

The 20" PS4S N0 Michelins will fit the 981 ok. Another R2 member has recently done this. Porsche say they are not approved for the 981 but that's best ignored. The higher load rating is not a problem. It would take a very pedantic warranty compliance person to quibble about the load rating difference.

The P-Zero N1 is a much improved tyre compared to the earlier N0 version. The P-Zero N1 are also dual compound construction. I'm not sure what the sc reference is.

Both P-Zero N0 and N1's are Standard Load. Michelin PS4S N0's are Extra Load and also dual compound construction.

I'll be interested to see how they perform on the track. In my northern location, hot dry conditions are rare, so it'll be a cool ambient temperature appraisal for me.

Brian

 

[Tony Warr]

Does any know why the very well reviewed PS4S are A wet rated but the N0 version are B wet rated. This is disappointing for a tyre that usually excels in the wet?

 

[AndrewCS]

Does any know why the very well reviewed PS4S are A wet rated but the N0 version are B wet rated. This is disappointing for a tyre that usually excels in the wet

In the N0 sizes 235 and 265/35 x 20 they are B (wet) rated ... Michelin`s response to my `very` enquiry was that it is down to the requirement of the N design. They also stated that the `margin of difference`to achieving an A rating was extremely small and did not warrant concern.

 

[Brian_Innes]

My Knockhill track session was extremely wet and very slippery with new tarmac sections laid only the previous day. (See separate post on my 982 718 Cayman S PDK thread.)

The Michelin PS4S N0 provided astounding wet road grip on the sections of track which could be described as "normal" tarmac.

The "B" rating of the N0 version of PS4S is probably down to the stiffer sidewall construction, and not the actual tread contact grip. The PS4S N0 is very, very, good in the wet. The best wet road tyre I have ever driven.

Brian

 

[ralphmusic]

As an aside, I stopped by Bristol Porsche and they had two new 991.2 GTS in the showroom, both with Michelin PS4S tyres although they are not listed as approved 991 summer tyres.

 

[ian harvey]

Brian, Ralph,

Very interesting last posts. I am going to ask my OPC about this. Yet to swap my tyres and can't quite get beyond the fact that the 4S would be great, not least around Spa in June if it rains!

Ian

 

[ian harvey]

Need to get an order placed. Has anyone bought any Cup 2s lately, where was the best deal, please?

 

[ralphmusic]

Need to get an order placed. Has anyone bought any Cup 2s lately, where was the best deal, please?

Ian,

I find that prices of tyres vary depending on who has stock. I always buy tyres only so I can use a preferred fitter. Also I often buy fronts or rears pairs separately as there is no discount for four tyres v two to get better pricing from different suppliers.

I have bought from eBay suppliers without encountering problems.

I have not found a trusted local supplier who will give me good service and broadly competitive pricing so I shop on-line for best price.

 

[ian harvey]

Thanks Ralph.

You are right, huge fluctuation in price. My local PC seemed to be very competitive until I realised they were quoting each and not pairs!

Interestingly, they said that 4Ss (NO) were available in my sizes but I think they must be wrong and cannot afford the time to wait and see so I've ordered the Cup 2s at 'mate's rates' from a local, reputable independent.

I've been watching the forecast at Spa for our trip later this month and it looks perfectly dry in which case my current tyres would be fine but we all know what can happen and heavily worn Cup 2s do not belong at a wet Spa. Last year my tyres ended up in a right old mess with half a kilo of 'pick-up' on every tyre....