Supersport 'issues' onto a 996 GT3

[lemmingjames]

Ok, long story short, need new rear tyres as current are starting to noticeably die.

Can stick with the PS2 in 295/30 or do i try the SS in 295/35?

From my understanding (websites), the difference in the tyre size would mean that the speedo under reads by a few mph (ie illegal), however, with PS2's on, it over reads (ie clock says 30, gps says 27 = legal)

So in theory, it would make the speedo more accurate as mine tends to be out by 3mph (gps vs clock)....

Though a friend of mine, who does test tyres for a living, suggests that "itd change the roll centres of the car." I admit this is something new to me but what are peoples thoughts on this?

The extra height of the sidewall is around 12mm

[keep it lit]

I've never messed with rear road tyre profile sizes tbh.. always 30 on the mk1 & 2 for obvious reasons like the one you've highlighted.

But I've messed about no end with slick tyre profiles on track.. on the mk1 you can really run what you want on the rear from 640 up to 680 with no real issues, actually the larger profile works well for traction and is kinder to the transmission over kerbs etc. On the Mk2 I had issues running larger profile slicks due to the much more sensitive ABS system (went into fail mode) and I'm sure this would be the same for a road tyre if you went to big with rear profiles.


off topic but as requested

[chriscoates81]

Just having a look;
PS2 PSS
Diameter 634.2mm 663.7mm
Circumference 1992.4mm 2085.1mm
Poke 42.6mm 100.7mm
Inset 122.6mm 140.7mm
Speedo error 0% -4.44%
Reading at 30mph 30mph 28.67mph
Reading at 60mph 60mph 57.33mph
Ride height gain 0mm 14.75mm
Arch gap loss 0mm 14.75mm

Im assuming you mean the rolling radius/ circumference will be different. 4% is quite a differnce between the 2.

[lemmingjames]

That gold carbon offends me, i thought about going with kevlar interior but having seen how it could end up like, taste has kicked back in

Anyway, heres a link to comparing them
http://tire-size-conversion.com/tire-size-comparis...


IM guessing its a no then, just stick to PS2's...

[keep it lit]

lemmingjames said:

That gold carbon offends me

I know

[chriscoates81]

Slippydiff said:

Stop faffing, put a set of Cup 2's on it.
PS2's are an old tyre now, and everyone knows Super Sports are for girls.

Then drive it the rain.

[nxi20]

I run 997.1 GT3 sized 19" wheels on my 996.2 GT3; one set with Supersports & another set with Cup2s - 245/35 fronts & 305/30 rears in addition to my 18" track slicks 235/640 & 285/660 sizes.

The speedo is still very slightly over-reading on 19" by 2 or 3% & is wildly over-optimistic on slicks.

No ABS problems on any of the above.

Edited by nxi20 on Thursday 28th May 19:26

[lemmingjames]

i was already about to push the go button on the Cup 2's and then i read NXI's post and has thrown me again.

then ive been reading old threads and notice the AD08 is being banded about and that the PS2 is due for replacement in September time this year (hopefully in 996 OEM sizes).

So what i want to know is how would the Cup2's hold up in the winter and when its raining.

[keep it lit]

I don't use my cars in the winter, and if it's raining I never push on the road in any season. Cup2's do seem to be very good in the wet though but I believe they don't like the real low temperatures.

Edited by keep it lit on Wednesday 27th May 12:52

[lemmingjames]

keep it lit said:

I don't use my cars in the winter, and if it's raining I never push on the road in any season.

think these, must be yours dude

[keep it lit]

Lol


golden balls

[lemmingjames]

Apparently no supersports (295/35/18) in the country or listed in stock at the several places (that i spoke to) that can get them. Camskill can get them but 3 day delivery wait as coming from France.

N4 PS2's going to be released in 6-8 weeks apparently. Not sure if this is the new tyre that was mentioned or not.

[PorscheGT4]

I am shocked they even bother still making PS2 full stop !

[lemmingjames]

Slippydiff said:

I heard someone enquiring about PS2's for A 996 GT2 this afternoon, the reply was they don't expect to make any until July.

Guess that ties in with the new compound being released. Some places i spoke to about the PSS's said (dont quote me) but Michelin UK dont know when theyll be getting the next shipment either. I wonder if the PSS's are going to be N-Rated as well?

[DAB964RS]

lemmingjames said:

i was already about to push the go button on the Cup 2's and then i read NXI's post and has thrown me again.

then ive been reading old threads and notice the AD08 is being banded about and that the PS2 is due for replacement in September time this year (hopefully in 996 OEM sizes).

So what i want to know is how would the Cup2's hold up in the winter and when its raining.

I'd be very wary about assuming. Cup 2s as an all year / all weather tyre. As Slippy says they are far superior in terms of wet weather grip than the original Cup tyres. Whilst driving across some moderately wet roads in North Wales last week I had a few instances where the rear wheels were losing grip under moderate acceleration. My friend who was following me in his 991 GT3 also had a few 'moments' - his car was also fitted with Cup 2s. I imagine in the depths of winter with lower temperatures Cup 2s would be bordering on dangerous unless you drive with extreme caution.

I think the PS2 or Continental N Rated tyres will serve you better if you want to enjoy your car all year round