Tires and 981

The most recent issue of Car & Driver tested nine performance tires (on a BMW with 17 inch wheels). The Pirelli P Zero came in dead last while the Michelin Pilot Super Sport was first. The P Zero is the standard tire on the new 981S 20 inch wheel. Tire Rack only lists the Pirelli Zero for the 981 with no alternatives (and at a VERY hefty price) - and the P Zero is back ordered. I hope there are some around somewhere in the case of a flat. Is the P Zero really that bad? I wonder if the results would be any different in a lower profile size than the size tested by C&D. Hopefully, Michelin and the other manufactures will have the correct sizes out before I need a set.

BTW, while perusing an issue of Excellence about the new 991, I noticed that they said the chassis guys at Porsche had been pushing for 20 inch wheels for some time. They said the 20 inch wheels have a larger tire patch - which let them reduce tire pressure "because the potential tire load is higher..." That, according to the article, "not only makes the car faster but also more comfortable." It seems counter intuitive that tires with the shorter side wall would be more comfortable - but that is what it said.

Lawdevil
2013 Boxster S - Agate Grey,
2016 Macan Turbo - jet black
Cashiers, NC & Atlanta

Since they used a BMW, none of the tires were N spec, and perhaps the Pirelli would be much better as such. While Porsche likely uses the same parameters as C and D (and or Tire Rack) the way they weight those parameters must be different.

Minus 40 degrees... Is that Fahrenheit or Celsius?

... on the same type of car that you intend to use the tires on, I would not give the results any validity.
The differences in weight distribution and power delivery between a Beemer and a 981 are staggering.
What may not work at all on a BMW may be just great on a Boxster.
Happy waiting
Pedro

Pedro Bonilla
1998 Boxster 986 - 311,000+ miles: [www.PedrosGarage.com]
PCA National Club Racing Scrutineer - PCA National HPDE Instructor - PCA Technical Committee (Boxster/Cayman)

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"Racing is life. Anything before or after is just waiting" ... Steve McQueen as Michael Delaney in "LeMans"

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"Being second is to be the first of the ones who lose" ... Ayrton Senna

Especially considering the Porsche sports car configuration is radically different from BMW's and most everyone else's. BMW is a good choice for general reference in that they have an "everyman" configuration, but are "sporting" nonetheless.

Minus 40 degrees... Is that Fahrenheit or Celsius?

In my experience is a very nice tire. Good QC, good stability, good wear (both on track and street). Note that all tires are trade-offs; and you have to define how you plan to use the tire to really decide which is best. For example, the Super sports are universally loved by reviewers and most drivers -- but they actually have a fairly abrupt break-away with less warning. But up to that point its a superior tire, and that point is higher than any of its competitors'. So, do you drive your car at 10/10ths? really?

The SSs also chunk to pieces on very rough auotcross-type courses (probably including some tight tracks). I actually saw Michelin replace a set with Bridgestones when big pieces began to fall off.

Now, i happen to really like the Supersports - i'm not bad-mouthing them. I may put a set on my Audi S6 at some point. My point is that you can't rate tires 0-100 without context any more than you can say "this Chateauneuf du Papes is RP97 and therefore it is ideal to have with Dover Sole". Uh, no. Try a nice Suavignon Blank or even Tavel. Even a more modestly reviewed one.

My first "track" tires (simply street tires that were dedicated to abuse) were P-zeros. They wore like iron and were very easy to feel as they squirmed and slid. I suppose they didn't have super high limits, but that was a long time ago.

PS/2s are slightly user friendlier.

Heck, for street driving i also like the Khumos i'm running, although i now shy away from track use since i found they neither stick nor hold up under serious abuse (like chasing down GT3s int he twisties).

Grant

Grant

gee-lenahan-at-gee-mail-dot-com

I saw that same article. The way they give points doesn't add up. Some of the more subjective tests award the most points and the ratios don't add up.

Minus 40 degrees... Is that Fahrenheit or Celsius?

But as Pedro said, it's critical as to what car they're on, and it gets particularly so because Porsches are so different. Keep in mind that "N-spec." There has been controversy as to whether it's merely put on tires approved by Porsche, or a different build. I go with the different build, and again, Porsche has their own way of weighting the various tire characteristics.

Minus 40 degrees... Is that Fahrenheit or Celsius?