The GT4 Tyre Thread

[Geneve]

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?

[Geneve]

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.

[Geneve]

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?

Edited by Geneve on Monday 29th August 11:22

[Geneve]

nudgerwilliams said:

Looks like there is an N-rated PZero in the right sizes for a more road tyre.

Not keen on Pirellis - what are the other N-spec tyres in similar sizes? Michelin Super Sports?

nudgerwilliams said:

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!

That's my experience with the Dunlops - light/even wear on the rears, but more rapid, and slightly unusual, wear on the fronts.

[Geneve]

Dunlop SMRs now replaced with Michelin PSC2s(at 2k mls )

First subjective impressions are of a better road and track tyre, and hopefully longer life. Did notice a bit more road noise on some m/way surfaces.

Still trying to work out which set of standard N-spec road tyres to put on my second set of wheels. Would prefer Goodyear Eagle F1 AS2s, but can't find anyone who can clarify if the 265/35s will fit on the 11" rears. They certainly fit on the Spyder's 10.5" rears?

[Geneve]

Pope said:

I would think the 265's would lend it an air of the VW stretch and poke trend...

Thanks Jon

What did you mean by that? Fitting slightly 'over' or 'under' sized tyres is not unusual, there's usually a degree of flexibility. Just be nice to have an expert opinion on the subject.

Pirelli do the exact sizes, but really not keen on them, and they are noisy. Would much prefer the GYs.

[Geneve]

OK, now sorted. Two sets of OE wheels and two sets of tyres.

The disappointing, short lived, Dunlops now replaced with Michelin MPCS2s for road/track and, aside from a tad more road noise, a better tyre IMO and likely to be much more durable.

Second set (year round road use), Goodyear Eagle F1 AS2s, fitted following liaison with Goodyear Technical - 235/35R20 N0 and 275/35R20 M2.

Ran them 'back to back' and very pleased. GYs quieter by several dB, especially on UK m/ways, and a noticeably more compliant feel, rounding out sharp bumps. Entirely subjective, but very sweet road handling, wet or dry. And good value - £800 all inc at Protyre.