The GT4 Tyre Thread
Discussion
Just wondered about experiences to date - what are people running, and the relative merits, or otherwise, of the various options?
Mine arrived on Dunlop MXX Race - with conspicuously little initial tread. One track day at Silverstone GP and the fronts are pretty much gone (may have allowed pressures to get a bit high - 2.6 bar) despite only 3-4 lap runs on a cool day.
Plan is to have two sets of wheels - one with road legal/track biased tyres (MPSC2? or MPSS?) with good wear rates, and a second set of pure road tyres for year round use ('N' spec with nice road driving characteristics).
Any thoughts?
Mine arrived on Dunlop MXX Race - with conspicuously little initial tread. One track day at Silverstone GP and the fronts are pretty much gone (may have allowed pressures to get a bit high - 2.6 bar) despite only 3-4 lap runs on a cool day.
Plan is to have two sets of wheels - one with road legal/track biased tyres (MPSC2? or MPSS?) with good wear rates, and a second set of pure road tyres for year round use ('N' spec with nice road driving characteristics).
Any thoughts?
In my experience Cup 2s wear a little better but not massively so. I find the Cup 2 fronts can last two whole days...something strange about the front tyre wear rates on this car.
I also believe the non N rated Cup 2s are much harder wearing than the N rated ones...but not sure whether overall grip is lower or not (in the non N spec). Interestingly over in the M3 world they are less impressed with the Cup 2s and believe they go off too quickly - probably a feature of the non N spec versions.
I bumped into AP at Goodwood FOS and enquired about the high front tyre wear rates on the GT4 - he just looked down at me with the 'you amateur' look and said his test drivers had not reported anything like this. Was frankly a little disappointed with his inability to listen as most of my friends - many experienced trackers - are all reporting similar findings. Maybe its an amateur thing but then that is the target market!
I also believe the non N rated Cup 2s are much harder wearing than the N rated ones...but not sure whether overall grip is lower or not (in the non N spec). Interestingly over in the M3 world they are less impressed with the Cup 2s and believe they go off too quickly - probably a feature of the non N spec versions.
I bumped into AP at Goodwood FOS and enquired about the high front tyre wear rates on the GT4 - he just looked down at me with the 'you amateur' look and said his test drivers had not reported anything like this. Was frankly a little disappointed with his inability to listen as most of my friends - many experienced trackers - are all reporting similar findings. Maybe its an amateur thing but then that is the target market!
I'm running the Dunlops and I really rate them, so much so I've just stuck another set on! Not sure why they have such a poor reputation on here, particularly how well they seem to perform on a track.
My only issues with the Dunlops is the wear rate as mine lasted <4k miles (I don't think cup2's are much better) and also the price (Cup2's seem to be cheaper)
My only issues with the Dunlops is the wear rate as mine lasted <4k miles (I don't think cup2's are much better) and also the price (Cup2's seem to be cheaper)
LaSource said:
I bumped into AP at Goodwood FOS and enquired about the high front tyre wear rates on the GT4 - he just looked down at me with the 'you amateur' look and said his test drivers had not reported anything like this. Was frankly a little disappointed with his inability to listen as most of my friends - many experienced trackers - are all reporting similar findings. Maybe its an amateur thing but then that is the target market!
I have to say I've not experienced this, but I have read that other have too... I found both the front and rear to have worn and pretty much worn at identical rates, first car I've ever experienced this with!MPSS are very much a road tyre only. keep those for your road wheels if you're going to get 2 sets. as a all round tyre the cup2 is pretty good imo....
The gt4 seems remarkably hard on it's front tyres though so I'm not sure cup2s will last very much longer. Oddly enough I've got a set of N spec cup2s on another car and they haven't shown anything like the amount of wear (fused the front left tread marks after 1.5 days in the gt4, nothing even close to that in the other) despite broadly similar geometry (0 front toe, -1.75 front camber).
The gt4 seems remarkably hard on it's front tyres though so I'm not sure cup2s will last very much longer. Oddly enough I've got a set of N spec cup2s on another car and they haven't shown anything like the amount of wear (fused the front left tread marks after 1.5 days in the gt4, nothing even close to that in the other) despite broadly similar geometry (0 front toe, -1.75 front camber).
isaldiri said:
MPSS are very much a road tyre only. keep those for your road wheels if you're going to get 2 sets. as a all round tyre the cup2 is pretty good imo....
The gt4 seems remarkably hard on it's front tyres though so I'm not sure cup2s will last very much longer. Oddly enough I've got a set of N spec cup2s on another car and they haven't shown anything like the amount of wear (fused the front left tread marks after 1.5 days in the gt4, nothing even close to that in the other) despite broadly similar geometry (0 front toe, -1.75 front camber).
As I've posted before, I believe the difference could be that the GT4 front rim is a little narrow for the wide 245 section tyres and hence you get a motorbike like bulge in the middle of the tyre. This could also explain why the fronts wear in the middle of the tyre and not the edges first - almost regardless of pressures or camber settings.The gt4 seems remarkably hard on it's front tyres though so I'm not sure cup2s will last very much longer. Oddly enough I've got a set of N spec cup2s on another car and they haven't shown anything like the amount of wear (fused the front left tread marks after 1.5 days in the gt4, nothing even close to that in the other) despite broadly similar geometry (0 front toe, -1.75 front camber).
Perhaps, in which case the fronts could be very pressure sensitive.
The wear is quite unusual - through the lhs of the centre block on both fronts. Rears wore fairly consistently.
Certainly these Dunlop fronts were barely road legal after just one track outing, and S.GP isn't particularly abrasive.
The wear is quite unusual - through the lhs of the centre block on both fronts. Rears wore fairly consistently.
Certainly these Dunlop fronts were barely road legal after just one track outing, and S.GP isn't particularly abrasive.
as can be seen fit what you like, people like cups people like Dunlops.
I am in the cup 2 camp as I hate Dunlops.
you will kill then on oem geo imo I run -2.2 and on 3k and track day they look ok still.
AS the OP found Dunlops over heat like a ***** and one can never dial in a pressure
Cups, you change the PSI twice and it's stable all day.
I am in the cup 2 camp as I hate Dunlops.
you will kill then on oem geo imo I run -2.2 and on 3k and track day they look ok still.
AS the OP found Dunlops over heat like a ***** and one can never dial in a pressure
Cups, you change the PSI twice and it's stable all day.
Edited by Porsche911R on Tuesday 2nd August 15:01
LaSource said:
As I've posted before, I believe the difference could be that the GT4 front rim is a little narrow for the wide 245 section tyres and hence you get a motorbike like bulge in the middle of the tyre. This could also explain why the fronts wear in the middle of the tyre and not the edges first - almost regardless of pressures or camber settings.
yeah i remember you mentioned that, 8.5J on the gt4 vs most other cars running 9s on 245s if I recall correctly. Oddly enough though it was the tyre shoulders that got battered worse for me than the middle so quite the opposite of you... 
I reckon GT4 is such a weapon I don't think the factory tyre choice will make a whole load of difference to the feel or performance of the car.
That said I was hoping for the Mitchelins on my car and have the Dunlops which I really can't fault. If anything once they get very hot on track the car becomes even more characterful, I mean that as a complement to the tyre and car set up in so much as some tyres seem to go off and the car is no longer fun. The GT4 remains consistent and fun from what I've found so far. Testing continues
The front tyre inner shoulder wear is odd, interesting thought on tyre width, I assumed it must have been temperature related.
That said I was hoping for the Mitchelins on my car and have the Dunlops which I really can't fault. If anything once they get very hot on track the car becomes even more characterful, I mean that as a complement to the tyre and car set up in so much as some tyres seem to go off and the car is no longer fun. The GT4 remains consistent and fun from what I've found so far. Testing continues
The front tyre inner shoulder wear is odd, interesting thought on tyre width, I assumed it must have been temperature related.
flat6gallivant said:
The front tyre inner shoulder wear is odd, interesting thought on tyre width, I assumed it must have been temperature related.
...slight update.Cup 2 fronts defo last no more than 2 track days ( or maybe even less!)...a day at Spa finished mine...and this is with shimmed cambered front axle.
Speaking to RSR yesterday another explanation was suggested - GT4 caster setting. If the caster means the wheel is sliding at an angle through corners then the centre tread block could get more scrub (picture a std merc saloon front axle caster)
Also wondering whether the spring rates are too soft
...maybe someone more knowledgeable about suspensions/steering can add something here.
if you go above the -2.2 I have, caster is an issue, so you need caster adjustment there after.
I would try the DSC controller if you track the GT4 as that stops the roll and dive on hard brakes they are only £950 and would sell well 2nd hand and seem to work.
you might not get faster laps with a DSC unit but you might have tyres which last a lot longer.
http://www.dscsport.com/2016/06/21/randy-pobst-mar...
I would try the DSC controller if you track the GT4 as that stops the roll and dive on hard brakes they are only £950 and would sell well 2nd hand and seem to work.
you might not get faster laps with a DSC unit but you might have tyres which last a lot longer.
http://www.dscsport.com/2016/06/21/randy-pobst-mar...
LaSource said:
Also wondering whether the spring rates are too soft
...maybe someone more knowledgeable about suspensions/steering can add something here.
is that not the nub of it all though, people want a more compliant road car that doesnt have 'fancy' tech so something has got to give? Up the spring rate and it becomes to harsh/average user wont enjoy the bumpy ride, make it softer and the average user enjoys it but at the expense of the track rat and the issues it may bring?...maybe someone more knowledgeable about suspensions/steering can add something here.
Porsche911R said:
as can be seen fit what you like, people like cups people like Dunlops.
I am in the cup 2 camp as I hate Dunlops.
you will kill then on oem geo imo I run -2.2 and on 3k and track day they look ok still.
AS the OP found Dunlops over heat like a ***** and one can never dial in a pressure
Cups, you change the PSI twice and it's stable all day.
http://www.pistonheads.com/gassing/topic.asp?h=0&t=1140774&r=26073520&hm=15789&mid=15789#26073520 I am in the cup 2 camp as I hate Dunlops.
you will kill then on oem geo imo I run -2.2 and on 3k and track day they look ok still.
AS the OP found Dunlops over heat like a ***** and one can never dial in a pressure
Cups, you change the PSI twice and it's stable all day.
Slippydiff said:
You gone back into mad stalker mode ? Wtf ! I was about the 1st person to try these, they won a few tests, and I like to try the best products, this is a 2012 thread
I hated the tyres and told people why and I thrown them away not even half worn. ,
The current Porsche 'approved' tyres for the GT4 are:
- Michelin Pilot Sport Cup 2
- Dunlop Sport Maxx Race
Both, F. 245/35 ZR20 N0 and R. 295/30 ZR20 N0
PEC use the Michelins on their GT4s (not sure if this is contractual) with standard set up and pressures. Wear rates vary, depending on weather conditions and driver skills (apparently most PEC customers are quite conservative on track).
There is an 'approved' Winter option - Michelin XTLT Pilot Alpin 4 N0 (F. 235/35 R20 and R. 275/30 R20 N0). So, there is some size allowances on the 8.5" and 11" rims.
Personally I'd prefer to have two sets of wheels and tyres - 'track' probably MPSC2s, but unsure what 'road' tyres. Are there any compatible 'N-spec' sizes in, ideally, Michelin Pilot Super Sports or Goodyear F1 Eagle ASs?
- Michelin Pilot Sport Cup 2
- Dunlop Sport Maxx Race
Both, F. 245/35 ZR20 N0 and R. 295/30 ZR20 N0
PEC use the Michelins on their GT4s (not sure if this is contractual) with standard set up and pressures. Wear rates vary, depending on weather conditions and driver skills (apparently most PEC customers are quite conservative on track).
There is an 'approved' Winter option - Michelin XTLT Pilot Alpin 4 N0 (F. 235/35 R20 and R. 275/30 R20 N0). So, there is some size allowances on the 8.5" and 11" rims.
Personally I'd prefer to have two sets of wheels and tyres - 'track' probably MPSC2s, but unsure what 'road' tyres. Are there any compatible 'N-spec' sizes in, ideally, Michelin Pilot Super Sports or Goodyear F1 Eagle ASs?
Edited by Geneve on Monday 29th August 11:22
Looks like there is an N-rated PZero in the right sizes for a more road tyre.
Have just replaced the front Cup2s on my car after three track days and 6 laps of the Ring. As others have said, wear pattern is a bit odd with the outside shoulder of the left front worn and the tread block inside the outer grove chamfered down below the wear bars. Rigth front tyre would probably do another day.
Rears more evenly worn and still with about 4.5mm tread left.
I've put more Cup2s on, but price is a bit alarming!
Have just replaced the front Cup2s on my car after three track days and 6 laps of the Ring. As others have said, wear pattern is a bit odd with the outside shoulder of the left front worn and the tread block inside the outer grove chamfered down below the wear bars. Rigth front tyre would probably do another day.
Rears more evenly worn and still with about 4.5mm tread left.
I've put more Cup2s on, but price is a bit alarming!
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