Cayman GTS Tire/wheel advice
#1
Cayman GTS Tire/wheel advice
Just did first HPDE in recently acquired 2015 Cayman GTS. Instructor (yes, I'm green) suggested upgrading my stock Pirelli P Zeros to street/comp tires to allow higher cornering speeds. Trouble is, Tire Rack shows NO street/comp tires for the GTS (front 8.5x20 235/35, rear 10x20 265/35), and only 4 Max Performance Summer tires.
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
#2
Just did first HPDE in recently acquired 2015 Cayman GTS. Instructor (yes, I'm green) suggested upgrading my stock Pirelli P Zeros to street/comp tires to allow higher cornering speeds. Trouble is, Tire Rack shows NO street/comp tires for the GTS (front 8.5x20 235/35, rear 10x20 265/35), and only 4 Max Performance Summer tires.
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
The MPSC2 should give you the grip you're looking for. You must be careful because they will not give you as much audible warning they are losing grip as the stock street tires will do. You'll have grip and the next thing you know you're spinning. You just need to get a feel for the tires' limits with experience.
#3
I like the MPSC2, but as you said, you expect a little more understeer with your 245 front, 295 rear. I'm afraid going to 245 front and sticking with 265 rear might induce more oversteer. I do not particularly want the car to be less stable, even if I get more grip, at least not at my current level of experience/skill.
I'm now thinking of going to 19" wheels with MPSC2s. There are better size options for 19" and it looks like I can stick with 235 front and 265 rear for now, and maybe go to 245 & 275 F/R in the future.
I'm having an interesting time matching wheels to the OEM offset. Is there a rule-of-thumb on how much I can differ without impact?
BTW; my original post was incorrect, in that 19" wheels ARE an option on the Cayman GTS.
I'm now thinking of going to 19" wheels with MPSC2s. There are better size options for 19" and it looks like I can stick with 235 front and 265 rear for now, and maybe go to 245 & 275 F/R in the future.
I'm having an interesting time matching wheels to the OEM offset. Is there a rule-of-thumb on how much I can differ without impact?
BTW; my original post was incorrect, in that 19" wheels ARE an option on the Cayman GTS.
#4
Rennlist Member
If you are in Green, there is no way that the tires would be your limitation. More coaching, smoother line, and right tire pressures. Yes, super sports are more popular tire but not at the point where you are in your learning curve.
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05' C2S
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05' C2S
#5
BTW: you'll get no argument from me about seat time being my biggest limitation.
#6
38-40psi should be good when hot, especially if you don't have much negative camber up front (higher pressure reduces edge wear somewhat).
As a novice, I wouldn't jump to MPSC2's yet as they are really R compound tires. Too much traction will slow your learning curve.
I would suggest Michelin PSS's ( Super Sports) as a nice step up, 235 or 245's in front and 265 or 275's in back. A 245/265 combo will work quite well, but the 235/265 or 245/275 combo's match slightly better. The PSS are very nice road tires too.
As a novice, I wouldn't jump to MPSC2's yet as they are really R compound tires. Too much traction will slow your learning curve.
I would suggest Michelin PSS's ( Super Sports) as a nice step up, 235 or 245's in front and 265 or 275's in back. A 245/265 combo will work quite well, but the 235/265 or 245/275 combo's match slightly better. The PSS are very nice road tires too.
#7
38-40psi should be good when hot, especially if you don't have much negative camber up front (higher pressure reduces edge wear somewhat).
As a novice, I wouldn't jump to MPSC2's yet as they are really R compound tires. Too much traction will slow your learning curve.
I would suggest Michelin PSS's ( Super Sports) as a nice step up, 235 or 245's in front and 265 or 275's in back. A 245/265 combo will work quite well, but the 235/265 or 245/275 combo's match slightly better. The PSS are very nice road tires too.
As a novice, I wouldn't jump to MPSC2's yet as they are really R compound tires. Too much traction will slow your learning curve.
I would suggest Michelin PSS's ( Super Sports) as a nice step up, 235 or 245's in front and 265 or 275's in back. A 245/265 combo will work quite well, but the 235/265 or 245/275 combo's match slightly better. The PSS are very nice road tires too.
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#8
Rennlist Member
Just did first HPDE in recently acquired 2015 Cayman GTS. Instructor (yes, I'm green) suggested upgrading my stock Pirelli P Zeros to street/comp tires to allow higher cornering speeds. Trouble is, Tire Rack shows NO street/comp tires for the GTS (front 8.5x20 235/35, rear 10x20 265/35), and only 4 Max Performance Summer tires.
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
Question is, can I go to a 19" or even 18" wheel to increase tire selection? 20" is the only factory wheel size for the GTS. Since 19" and 18" are not options, what would they do to all the electronics, like antilock, PTV, PSM, etc. It was suggested to me that they might not function correctly with non-factory option size wheels/tires. Anyone know?
If that fails, would Michelin Pilot Super Sport tires support greater lateral G-forces, i.e higher cornering speeds?
consider
Yoko AD08R
Hankook R-S3
and Michelin MPSS
as tyre alternatives.
Make sure any new wheels clear your calipers / rotors
Have fun, even "new guys" can benefit from dedicated DE wheels.
Craig
#9
Please do not buy R-comp tires yet.. As others have said stickier rubber will hamper your learning curve. More and more driving clubs including some PCA chapters are not allowing green and novice students R-comp tires on the track.. Which I fully endorse.. Run through a few sets of street tires first, with the Michelin pilot super sport as a great tire.. BTW, a smooth driver could be very fast on track with these PSS's..
As you will discover over time this sport can suck you in.. Stickier tires means getting better brakes, and now with tires and brakes you need to adjust or change the suspension.. Oh let's remember safety , maybe ahead of the others. Harness, seats, roll cage.. Etc..
It's a blast.. Take your time and enjoy yourself.
As you will discover over time this sport can suck you in.. Stickier tires means getting better brakes, and now with tires and brakes you need to adjust or change the suspension.. Oh let's remember safety , maybe ahead of the others. Harness, seats, roll cage.. Etc..
It's a blast.. Take your time and enjoy yourself.
#10
Instructor
Speaking of tire pressure, I started at 33lb in the p Zeros, and let out air at the end of each session, as needed (while hot off track), to bring the pressure back down to 39lb. I was told to keep it below 40lb. Does this seem reasonable?
BTW: you'll get no argument from me about seat time being my biggest limitation.
BTW: you'll get no argument from me about seat time being my biggest limitation.
he said that to get the best performance from the cup 2 tires, keep HOT tire pressure near 34 psi. if it gets a bit slick, move it down to Porsche recommended 31 PSI HOT.
He recommended running 4-6 hot laps in the first run group, pulllng off and bleeding air out - with a pressure guage, do not trust TPMS readings.
and if you are driving them home, REFILL them before you leave the track.
#11
OK, who put on that HPDE? Non of the PCA instructors I know will ever suggest to a green student to get comp tires. There is way to much for the student to learn before he should go there.
#12
I was also told by a Michelin tech re the MPSS; "36-38 psi hot should put you in the optimum range for HPDE".
#13
Three Wheelin'
Look at Dunlop Direzza ZII Start Spec as a great street/track/AX tire
Don't know if they come in your sizes.
They are just under Potenza RE-71's in grip and better than MPSS or MPS2
They have been one of the hot tires for a few years now and now the RE-71 is the hot tire
I have MPSS as my DD tires, they are not as good as others for track use. I currently am using the Star Spec for track/ax and will probably go with RER-71 when they wear out
My car is bone stock BTW
Michelin tires are not necessarily better than others, just more expensive, although they do have world class customer service and actually have tread life warranty on most tires. The only reason I have MPSS as my DD tire is they were free!, otherwise I probably would have gone with Sumitomo HTR ZIII which are around 1/2 the cost of MPSS and perform really well. I have tracked the HTR ZIII's and they were not bad at all . My Star Specs are a few seconds faster
As others have said, do not get R-comp tires. You will need to do other mods like suspension to really take advantage of them and with a stock suspension, you can really get more than .7 deg neg camber on the front and you need lots more with R-comps
Don't know if they come in your sizes.
They are just under Potenza RE-71's in grip and better than MPSS or MPS2
They have been one of the hot tires for a few years now and now the RE-71 is the hot tire
I have MPSS as my DD tires, they are not as good as others for track use. I currently am using the Star Spec for track/ax and will probably go with RER-71 when they wear out
My car is bone stock BTW
Michelin tires are not necessarily better than others, just more expensive, although they do have world class customer service and actually have tread life warranty on most tires. The only reason I have MPSS as my DD tire is they were free!, otherwise I probably would have gone with Sumitomo HTR ZIII which are around 1/2 the cost of MPSS and perform really well. I have tracked the HTR ZIII's and they were not bad at all . My Star Specs are a few seconds faster
As others have said, do not get R-comp tires. You will need to do other mods like suspension to really take advantage of them and with a stock suspension, you can really get more than .7 deg neg camber on the front and you need lots more with R-comps
#14
Look at Dunlop Direzza ZII Start Spec as a great street/track/AX tire
Don't know if they come in your sizes.
They are just under Potenza RE-71's in grip and better than MPSS or MPS2
They have been one of the hot tires for a few years now and now the RE-71 is the hot tire
I have MPSS as my DD tires, they are not as good as others for track use. I currently am using the Star Spec for track/ax and will probably go with RER-71 when they wear out
My car is bone stock BTW
Michelin tires are not necessarily better than others, just more expensive, although they do have world class customer service and actually have tread life warranty on most tires. The only reason I have MPSS as my DD tire is they were free!, otherwise I probably would have gone with Sumitomo HTR ZIII which are around 1/2 the cost of MPSS and perform really well. I have tracked the HTR ZIII's and they were not bad at all . My Star Specs are a few seconds faster
As others have said, do not get R-comp tires. You will need to do other mods like suspension to really take advantage of them and with a stock suspension, you can really get more than .7 deg neg camber on the front and you need lots more with R-comps
Don't know if they come in your sizes.
They are just under Potenza RE-71's in grip and better than MPSS or MPS2
They have been one of the hot tires for a few years now and now the RE-71 is the hot tire
I have MPSS as my DD tires, they are not as good as others for track use. I currently am using the Star Spec for track/ax and will probably go with RER-71 when they wear out
My car is bone stock BTW
Michelin tires are not necessarily better than others, just more expensive, although they do have world class customer service and actually have tread life warranty on most tires. The only reason I have MPSS as my DD tire is they were free!, otherwise I probably would have gone with Sumitomo HTR ZIII which are around 1/2 the cost of MPSS and perform really well. I have tracked the HTR ZIII's and they were not bad at all . My Star Specs are a few seconds faster
As others have said, do not get R-comp tires. You will need to do other mods like suspension to really take advantage of them and with a stock suspension, you can really get more than .7 deg neg camber on the front and you need lots more with R-comps
I've received similar advice re R-comp tires; I'd need to beef up brakes and suspension. I'm trying avoid starting down that slippery slope.
#15
On Tire Rack, the ZII only have 2 sizes, one 17" and one 18". So even if I went to 18" wheels they would not have the front/rear sizes. The RE-71R do come in Cayman sizes, so they would be worth looking at when my current tires wear out. Similar to you, maybe MPSS for DD and RE-71R for DE/track.
I've received similar advice re R-comp tires; I'd need to beef up brakes and suspension. I'm trying avoid starting down that slippery slope.
I've received similar advice re R-comp tires; I'd need to beef up brakes and suspension. I'm trying avoid starting down that slippery slope.