tmg57

Thanks, Mike. I recall it now. I reread the maintenance recommendations from the GT3 book and noticed the wording about slicks. Porsche was very straightforward in stating that slicks are prohibited because "they subject the chassis and body components to potentially higher loads than those for which they are designed".

The 911 manual states that "the fitting of racing tires for sporting events is not approved by Porsche. Very high cornering speeds can be achieved with racing tires. The resulting transverse acceleration values would jeopardise (sic) the adequate supply of oil to the engine".

From this we can infer (not really, but just for fun):

1. The GT3's true dry sump works better than the 991's integrated dry sump (no surprise) and,

2. The 911 has stronger chassis and body components. Hmmmm..... maybe there is something to that RWS rumor after all.

tmg57

It seems to me that the dealer would normally be on your side in trying to get warranty approval from PCNA. If approved, they get the work and get paid by a reliable source. If denied, you may take the work down the road to an indy shop. However, this might not hold if PCNA reimburses at substantially discounted rates. Anybody know?

frayed

Maybe.

But could it just be that PAG didn't build the car around slicks and wants to wash their hands of part failure if the extra loads did cause a problem. But that's different than guaranteeing a problem.

I'm certain that some people reading this will run slicks at some point. Unfortunately that puts us all in beta test mode, looking to the aftermarket to fix weaknesses if they do arise.

tmg57

I agree. I just enjoyed the entirely different reasoning for the 911 vis-à-vis the GT3.

Mike in CA

Tom, I thought the forum might be interested in this info I just passed on to you in our PM exchange. It doesn't relate to slicks specifically, but it is on topic with regard to warranty and track use which was also speculated about in that other thread. This seems more definitive....

The 991 GT3 warranty booklet says the following:

Components and/or parts that fail during racing or driving events (including Porsche sponsored events) may not be covered by the new car Limited Warranty. (My emphasis)

The language in the warranty booklet for my 997.2 Carrera used the exact same wording, except that "will not" was substituted for "may not".

This seems consistent with the wording in the Race Circuit booklet that came with the 991 GT3 that suggests that coverage may be continued as long as certain enhanced maintenance procedures are followed. And, apparently, as long as you don't use slicks.

tmg57

^...Good info, Mike. Kudos to Porsche for addressing this issue. Obviously it is very important to RL'ers.

Gofishracing

sunnyr
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I wonder how Porsche will know if some one uses slicks and swaps them out? Record G forces?

Exactly what i was going to ask. I doubt there is really a way for them to tell. some drivers drive harder than others and would generate more G Forces. some on slicks don't generate as much as some drivers on DOT R's

frayed

fixed it for you.

philstireservice

It usually says " not for highway use" on the side of a Hoosier.

008

DOT=department of transportation. Not for highway use is different than not for street use generally. Racing tires are not DOT approved that is the clear and simple distinction, this has been litigated although a while ago, and have not found the info recently. If a tire is DOT approved and is really just used for racing its still a street tire by definition. There was also a GTR lawsuit about this concerning Toyo R888s that was settled around tranny failures. The normal caveats apply about getting info from forums and you should use your own discretion but to the OPs original post, the SC2 is an R compound tire so your dealer is either ignorant of the terminology or misinformed from their source.

Alan Smithee

Maybe by your definition. As I posted earlier, the tire manufacturers do not make the same distinction.

008

It's not my definition, it's the department of transportation's. If a tire is "DOT approved", it's approved for use on the street. The tire manufacturers know what they'll really be used for and do just enough to get them approved so they can be run in street tire racing classes, that is the genesis of the "R" compound tire. They will advise against it in the more focused tires because of their construction they are more susceptible to road debris and at highway speeds they lack the reinforcement to hold together as well as other modern belted tires. It's a CYA statement. Where Porsche makes the distinction though, is a whole other ball of wax.

Dan39

You guys are debating tires that do not exist (slicks in 245/305-20)...

Would love to hear about anyone fitting 19s, though.

Macca

008 definitions of DOT etc are accurate IMO. How PAG see "racing tyres" is a barrel of worms. Dan39 point is most pertinent. In our country they have to prove something you fitted after market causes the issue you are claiming warranty. You put an aftermarket face plat on an iphone and the RF module fails and the phone manufacturer cant blame the face plate and refuse warranty. Seems logical....

Alan Smithee

Seems pretty simple to me - if a manufacturer advertises a tire for street use, you have legal ground to stand on. If a manufacturer makes it clear a tire is to be used on track only, it is going to be a steep uphill battle to get warranty coverage for a part failure related to increased cornering loads, etc.

DOT tires conform to labeling requirements, but a tire designed for racing is dangerous on the street, and vice-versa. Local law determines street legality regarding tread depth; it may not take many revolutions for a "street legal" DOT racing tire to become illegal for street use, regardless of labeling.