knfeparty

Hey the guy on the red bike and the camo hat rolling up to the BFG truck at 2:39 is me!

XPC5

The white Cayman at 1:12-1:14 is mine

knfeparty

I think my dad came and talked to you about strapping the car down on the trailer. You were at the end of our row in paddock I think.

PedalFaster

Got a response today, and unsurprisingly the onus is on the person running the wheels to find proof that they're legal:

I'm currently on paternity leave and thus have a lot of free time on my hands, so I'll write Porsche Cars North America and the PCA technical committee and see if either of them can help clear things up.

It looks like the SAC's working through a backlog of letters -- sjfehr, did you get a response to yours?

BGLeduc

Have you looked in the Porsche Parade Competition Rules? Appendix VI lists the specs for all Porsches, including wheel sizes. If you need a copy, it can be found here:

http://parade2013.pca.org/docs/2013_PCR_Appendix_VI.pdf

abqautoxer

No backlog, those are all letters that came after the day of our last meeting, we (the SAC) meet monthly on the second Tuesday normally. We met more often for Street/Stock class discussions.

Brian's idea is a good one IMO.

edfishjr

Fascinating! First of all, they seem to have the columns labeled wrong. "Option" column appears to be the base or standard wheel/tire combo.

In any case, PCA apparently recognizes 8.5/10.5 wheel width combos for all Boxsters and Caymans in 2010-11 (code 83), but not 2009 where they recognize a 9.5 rear wheel maximum. That seems like good information. But then, astoundingly, 07-08 Base Caymans had an 8/11 option (code 62), but 07-08 CaymanS did not? Really? You could get (and run in the Parade autocross) wider wheels with the Base than the S on 07-08 cars? Seems fishy.

Edit: I now suspect, after looking at pictures and comparing the offsets, that the 2006CaymanS I saw with 8.5 and 10 Carrera Sport 10-spoke wheels, definitely ordered with non-existent option XRR, could have put on a set of the Cayman R/Boxster Spider wheels. Either that, or that's what option XRR was before the R and Spyder existed. Probably no way to ever know and not recognized by Appendix VI.

BGLeduc

You are correct. Thanks for catching that.

I passed it along to the head of the PCA Parade rules committee.

Brian

Audii-Dudii

According to pp. 43 and 92 of the 2007 Cayman brochure -- a .pdf copy of which you can find at http://www.auto-brochures.com/makes/...ayman_2007.pdf -- wheel option XRR (19x8.5/19x10) was clearly available ... QED.

Although I can't put my hands on a .pdf copy of it just now (it's on another computer), I also have an order guide from early 2006 that shows the XRR option was available for late-build 2006 cars as well, unlike the August and September 2005 order guides that are floating around the internet.

As such, I am completely comfortable that using these wheels on a 2006-2008 Cayman, both S and base models, is legal per the SCCA rules and am confident that it can be successfully defended should it ever be protested.

To my mind, a trickier question (and one that parallels SJFehr's question about how much of the PASM option has to be retrofitted in order to use its stiffer springs on a non-PASM car) is whether the "Sport Mode" upgrade Porsche now offers for these cars is likewise legal per SCCA rules.

As you may or may not be aware, the Sport Mode upgrade duplicates all of the software-based performance changes the Sport Chrono option enabled on those cars where it was installed originally, except that it doesn't have the dash wart and it wasn't available when these cars were sold new.

Aside from the display function provided by dash wart (and the presumably minor weight savings that comes from not installing it), the performance of Sport Chrono and Sport Mode equipped cars is otherwise identical.

While retrofitting the Sport Chrono option is both legal and technically possible (ditto for the PASM option), it's also cost prohibitive, which is what makes the Sport Mode upgrade so appealing. A car so equipped will not gain any competitive advantage compared to a car that was originally equipped with the Sport Chrono option, but it does allow people to upgrade cars that don't have it installed so they're not at a competitive disadvantage, which is the case now, and it allows them to do so without having to pay many thousands of dollars to also install the one part of the option that doesn't have any effect on performance.

This all seems pretty logical to me, but what do I know? Perhaps allowing it for Boxsters and Caymans creates a slippery slope for other cars?

PedalFaster

How is "Sport Mode" acquired? If it's a dealer-installed / Tequipment accessory, which it sounds like it is, it's unambiguously not legal no matter how closely it resembles Sport Chrono.

When you have a chance, can you scan the 2006 brochure, and also check if it lists dimensions for the XRR wheels?

Thanks!

Edit: I don't think the Sport Mode question is particularly parallel to the PASM one. The rules already allow for replacement of the shocks, so the PASM question is a fairly narrow request for clarification on whether shock electronics and associated switches are considered part of the shock absorber for the purposes of the rule. On the other hand, Sport Mode presumably entails an ECU reflash, which is in no way Stock / Street legal.

PedalFaster

That's unfortunately not new information. The legality of the XRR wheels is not in question -- the dimensions of the wheels are. Take a look at the letter I wrote for more information: https://rennlist.com/forums/10760244-post148.html.

Audii-Dudii

Okay, then howzabout this: Porsche's parts catalog clearly identifies the XRR option wheels as "8.5 J x 19 Et 55" and "10 J x 19 Et 42" and there is no listing for an 11.5" wide wheel. See for yourself at http://www.porsche.com/usa/accessori...artscatalogue/

Audii-Dudii

From Porsche's parts catalog:





Does this absolutely, positively prove that these wheels, in these sizes, were available on the 2006-2008 Cayman S? No, only a window sticker showing they were delivered on a car and a delivery photo showing they were actually installed will do that ... maybe.

IMO, though, in combination with the sales brochure and order guide, this does meet the requirements of Rule 3.8 to establish that: 1) XRR was an available option and 2) XRR wheels are 19x8.5 and 19x10. Per Rule 8.3.1, this then puts the burden of proof that they were / are not a legal option for 2006-2008 Caymans back on the protester (and in view of all the confusion around this issue, good luck to them!)

Also, the order guides do not show any conflict between the XRP spacer option and the XRR wheel option, so they can be legally installed together.

PedalFaster

Agreed, even before the parts catalog screenshots (which, incidentally, are for the 2008 car). Ideally there would be a way to bring the official parts catalog (not an eBay / internet copy) with you to events, but I agree that showing a preponderance of evidence suggesting that the wheels are legal puts the onus of proof back on the protester.

Audii-Dudii

The screen shots I provided came from the .pdf hosted at Porsche's web site, so all one would need to view them during a protest at an event is a phone or notebook computer with internet access. That said, Porsche does sell a parts catalog DVD for only $9.00 (it's at the bottom of the page I linked to), so it probably is a smart idea to buy one and bring it to events, just in case.

As for the screenshots being for a 2008 car, this is the parts catalog that Porsche chose to provide for "2005-2008" Caymans, so I assume they're satisfied that it's applicable to each of those model years. (FWIW, I did note a few instances where there are references to 2006 and 2007 in the remarks column.)

Alas, absent a clarification letter from the SCCA, until a protest is filed and a ruling made (and upheld on appeal!), none of us will know for certain how the SCCA will view the legality of using 19x8.5/19x10 XRR option wheels on 2006-2008 Caymans. I've weighed both sides of the issue and am comfortable enough with my decision to have purchased several sets of wheels accordingly (and still have the 19" Sport Design wheels that came on my car as a worst-case backup), but YMMV...

That said, I believe this is largely a non-issue, because I'm fully expecting to get my butt kicked by any number of Corvettes next year. I have done some casual back-to-back comparisons against a friend's Z06 and IMO, it doesn't seem to me its performance on street tires suffers all that much more than my Cayman does, and if true, then it will make a well-driven one very difficult to catch, let alone beat, which will reduce the odds of ever being protested considerably. <shrugs>