Michelin PS Cup 2: Any difference between N spec and non N?
Discussion
Hi, before I obtain another set of Cup 2 tyres in 996 GT3 sizes, I was wondering whether there was any evidence of the difference between N-spec and non N-spec versions of this tyre.
I've had a couple of sets and 'I think' I had the following experience:
My first set was non N spec - they seemed a harder compound, potentially went off after a few hot laps, but lasted a long time.
My second set was N spec - they seemed to be a softer compound, more grip, higher wear rate, and bigger tail off with multiple heat cycles.
Now you may say I have answered my question above, however I am not a pro and was getting faster by the second set anyway which may have led to a different level of load on the tyres.
So, does the above experience correlate with anyone else?
I've had a couple of sets and 'I think' I had the following experience:
My first set was non N spec - they seemed a harder compound, potentially went off after a few hot laps, but lasted a long time.
My second set was N spec - they seemed to be a softer compound, more grip, higher wear rate, and bigger tail off with multiple heat cycles.
Now you may say I have answered my question above, however I am not a pro and was getting faster by the second set anyway which may have led to a different level of load on the tyres.
So, does the above experience correlate with anyone else?
The answer is yes they are different, only Michelin will know by how much but there is a big variety of construction, compound etc. possibilities. The end result to the car could be significant in all aspects of how it drives, steers and rides. Given the quirk of 911 weight distribution and rear engine I wouldn't put a non N on my car (and if it holds any weight I work on chassis and tyre development, with Michelin and Pirelli etc.)
Thanks.
I appreciate that a risk minimisation approach would be to just stick with N spec 'just in case'. However, I personally do not feel there is a great safety issue with the different specs. I tracked my first set (which were only available in non N spec at the time) extensively at Silverstone, Spa, and the Nurburgring - they worked fine in terms of safety, albeit a little different performance characteristic.
It is also not always clear to me whether the N spec is actually designed for the car in question. e.g. I believe the CGT front is the same tyre as a Cayman rear? (I might be wrong about which two models). The 996 GT3 sizes I don't believe were tested for that model as it was some 10 years out of production.
In M3 world many track drivers are mixing N and non-N spec across the two axles though I have yet to confirm the thinking behind this.
Many of my track going friends have found the latest N spec variant of the PS Cup 2 (on GT4 and 991RS cars) to have higher wear rates and some noticeable impact of multiple heat cycles. Though these later cars, being in warranty, run only N spec. This may not just a function of N spec to non N spec, it may also be that Michelin adjusted the tyre compound between earlier releases of the N spec tyre to the later releases
Anyway I am not challenging your view but just wanting to see whether there is any feedback from people who have used both variants.
I appreciate that a risk minimisation approach would be to just stick with N spec 'just in case'. However, I personally do not feel there is a great safety issue with the different specs. I tracked my first set (which were only available in non N spec at the time) extensively at Silverstone, Spa, and the Nurburgring - they worked fine in terms of safety, albeit a little different performance characteristic.
It is also not always clear to me whether the N spec is actually designed for the car in question. e.g. I believe the CGT front is the same tyre as a Cayman rear? (I might be wrong about which two models). The 996 GT3 sizes I don't believe were tested for that model as it was some 10 years out of production.
In M3 world many track drivers are mixing N and non-N spec across the two axles though I have yet to confirm the thinking behind this.
Many of my track going friends have found the latest N spec variant of the PS Cup 2 (on GT4 and 991RS cars) to have higher wear rates and some noticeable impact of multiple heat cycles. Though these later cars, being in warranty, run only N spec. This may not just a function of N spec to non N spec, it may also be that Michelin adjusted the tyre compound between earlier releases of the N spec tyre to the later releases
Anyway I am not challenging your view but just wanting to see whether there is any feedback from people who have used both variants.
Edited by LaSource on Wednesday 11th January 22:31
Someone I know has run N spec 991gt3 cup 2 rears and K (Ferrari) spec speciale tyres on a 12c and is adamant that the N spec has a firmer sidewall and the tyre carcass deflects less under load. iirc he thought that the k spec tyre was slightly softer as well and was wearing a fair bit quicker.
c4sman said:
One of the things I like about my pork is that when I turn in at 80mph some German test pilot (hopefully Walter or Andreas) has done it many times before much faster than me with the same set up and tyres. 
The story is that the 996GT2 got an extra inch on the rears (12" vs 11" for the 996) and extra 10mm wider rubber because the back end stepped out on Walter going into the left hander after the bridge on the main Nurburgring straight. He was doing close to 290km/h 
There was a chap from Michelin UK posting on the forum a while back with some really useful advice. Wonder if Jamie is still around? See old thread below.
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
http://www.pistonheads.com/gassing/topic.asp?h=0&a...
Cheburator mk2 said:
The story is that the 996GT2 got an extra inch on the rears (12" vs 11" for the 996) and extra 10mm wider rubber because the back end stepped out on Walter going into the left hander after the bridge on the main Nurburgring straight. He was doing close to 290km/h
That is the same story for the 997 GT2, already 12" but "apparently" Walter decided it needed 325 section rubber after the same experience at the same location !anonymous said:
[redacted]
Can't comment on the specifics but one car will always lead the tune. They may choose to carry a spec over from a different car and tune the chassis to suit, or vice versa, either way if it's approved you know the chassis and tyre combination has met whatever targets they have developed to.Tyre performance can vary so massively depending on how they've constructed it and compound and it's the single most important part on the car as it's the bit making the car actually go, stop and corner, plus no other single part can affect so much of the car's behaviour. It's just a case of risk management, lowest risk equals N spec.
LaSource said:
Thanks.
I appreciate that a risk minimisation approach would be to just stick with N spec 'just in case'. However, I personally do not feel there is a great safety issue with the different specs. I tracked my first set (which were only available in non N spec at the time) extensively at Silverstone, Spa, and the Nurburgring - they worked fine in terms of safety, albeit a little different performance characteristic.
It is also not always clear to me whether the N spec is actually designed for the car in question. e.g. I believe the CGT front is the same tyre as a Cayman rear? (I might be wrong about which two models). The 996 GT3 sizes I don't believe were tested for that model as it was some 10 years out of production.
In M3 world many track drivers are mixing N and non-N spec across the two axles though I have yet to confirm the thinking behind this.
Many of my track going friends have found the latest N spec variant of the PS Cup 2 (on GT4 and 991RS cars) to have higher wear rates and some noticeable impact of multiple heat cycles. Though these later cars, being in warranty, run only N spec. This may not just a function of N spec to non N spec, it may also be that Michelin adjusted the tyre compound between earlier releases of the N spec tyre to the later releases
Anyway I am not challenging your view but just wanting to see whether there is any feedback from people who have used both variants.
Cayman doesn't have a N spec Cup2 or Pilot Super Sport tyre, it just so happens that the CGT front is the same size as Cayman rear.I appreciate that a risk minimisation approach would be to just stick with N spec 'just in case'. However, I personally do not feel there is a great safety issue with the different specs. I tracked my first set (which were only available in non N spec at the time) extensively at Silverstone, Spa, and the Nurburgring - they worked fine in terms of safety, albeit a little different performance characteristic.
It is also not always clear to me whether the N spec is actually designed for the car in question. e.g. I believe the CGT front is the same tyre as a Cayman rear? (I might be wrong about which two models). The 996 GT3 sizes I don't believe were tested for that model as it was some 10 years out of production.
In M3 world many track drivers are mixing N and non-N spec across the two axles though I have yet to confirm the thinking behind this.
Many of my track going friends have found the latest N spec variant of the PS Cup 2 (on GT4 and 991RS cars) to have higher wear rates and some noticeable impact of multiple heat cycles. Though these later cars, being in warranty, run only N spec. This may not just a function of N spec to non N spec, it may also be that Michelin adjusted the tyre compound between earlier releases of the N spec tyre to the later releases
Anyway I am not challenging your view but just wanting to see whether there is any feedback from people who have used both variants.
Edited by LaSource on Wednesday 11th January 22:31
When I spoke to the Michelin Cup2 engineer about my CSL they told me to fit the N-spec front (not plain aftermarket) with the standard aftermarket rear, but I never bought any.
The 991 RS shares its front tyre size with the 918 but the spec is different, N0 is a 96Y load on the 918 (lap time special which wears out in 5 minutes) and RS has a N1 99Y load which lasts much longer. GT4 should have a unique spec but that also wears Dunlops out pretty fast so think it needs more camber in reality.
Worth noting that an N doesn't mean it's approved on all Porsches that have the same size, they will be model specific.
As has been said are you sure the Cup2 N is an approved spec on the 996 GT3 anyway?
Pookster said:
Cayman doesn't have a N spec Cup2 or Pilot Super Sport tyre, it just so happens that the CGT front is the same size as Cayman rear.
When I spoke to the Michelin Cup2 engineer about my CSL they told me to fit the N-spec front (not plain aftermarket) with the standard aftermarket rear, but I never bought any.
The 991 RS shares its front tyre size with the 918 but the spec is different, N0 is a 96Y load on the 918 (lap time special which wears out in 5 minutes) and RS has a N1 99Y load which lasts much longer. GT4 should have a unique spec but that also wears Dunlops out pretty fast so think it needs more camber in reality.
Worth noting that an N doesn't mean it's approved on all Porsches that have the same size, they will be model specific.
As has been said are you sure the Cup2 N is an approved spec on the 996 GT3 anyway?
Both the 918 N0 spec tyres are exactly the same size as the 991 RS which are in N1 spec. the major difference outside of much higher load rating on the RS tyres are that the N0 918 tyres had better rolling resistance to achieve some silly eco type nonsense.When I spoke to the Michelin Cup2 engineer about my CSL they told me to fit the N-spec front (not plain aftermarket) with the standard aftermarket rear, but I never bought any.
The 991 RS shares its front tyre size with the 918 but the spec is different, N0 is a 96Y load on the 918 (lap time special which wears out in 5 minutes) and RS has a N1 99Y load which lasts much longer. GT4 should have a unique spec but that also wears Dunlops out pretty fast so think it needs more camber in reality.
Worth noting that an N doesn't mean it's approved on all Porsches that have the same size, they will be model specific.
As has been said are you sure the Cup2 N is an approved spec on the 996 GT3 anyway?
You also said earlier that you wouldn't put non N spec tyres on your car. I do however recall seeing standard non manufacturer stamped Michelin Supersports on various Porsche cars at the German driving school as well as the Experience Centre here in the UK so it seems Porsche themselves are somewhat less fussed about the N rating other than ensuring one pays the N spec tax (whether on the approved model or not) simply to get the warranty approved.
I've used both N spec and non N spec Cup 2s on a 997 for a few years now on road and track during Summers. I agree the non N spec lasts longer - managed over 25000 miles on my rears which are down to 1.6mm - fronts are still at 3mm. I just buy whichever is cheapest at the time. At the moment the n rated tyres in my sizes are cheaper and I'll be needing rears very soon! I've noticed the n rated new now have a tyre rim protector built in like the old PS2. My dilemma is whether i replace the fronts too to keep the compound matching on all four corners.
anonymous said:
[redacted]
That Porsche actually tests the tires on the cars, so you can be sure that they will be perform with your car. Sorry, only in German and about older models, but you'll get the idea:https://www.auto-motor-und-sport.de/news/so-testet...
If your requirements differ from that of a "normal" driver you may want to choose different, more modern tires, but you will not know how they perform and may need to try a few models before you find the right one for you. However, for normal road use somebody like me, who´s not a "racer" is safe when choosing N-rated, as I know, the car will be driving well.
Cayman48 said:
Sorry to pop up this old post, i felt it was the perfect place to talk instead of a new post.
Since we can't find cup 2 N stamped for 996 gt3 sizes, what do you guys do ?
- Non N ?
- another brand with N ?
(Sorry for my english, I'm french)
Although I mentioned N spec 996 GT3 tyres at the beginning of this thread, I think I was mistaken.Since we can't find cup 2 N stamped for 996 gt3 sizes, what do you guys do ?
- Non N ?
- another brand with N ?
(Sorry for my english, I'm french)
I'm quite sure I just used non-N spec all the time....and I am very happy with them and recommend them thoroughly
Cayman48 said:
Sorry to pop up this old post, i felt it was the perfect place to talk instead of a new post.
Since we can't find cup 2 N stamped for 996 gt3 sizes, what do you guys do ?
- Non N ?
- another brand with N ?
(Sorry for my english, I'm french)
Used non N on 996 GT3 and now CGT no issues at all.Since we can't find cup 2 N stamped for 996 gt3 sizes, what do you guys do ?
- Non N ?
- another brand with N ?
(Sorry for my english, I'm french)
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