Probably to save their transmissions from driver error...... Should be expected.

 

Did any of the instructors comment on how the Z/28 compared to the Z51?

 

They said the Z/28 is faster stock v stock and just incredible and unflappable on the track. However, put better tires on the Z51 and some good brake fluid/track pads and the Stingray will likely outperform on most tracks. Really can't go wrong with either car.

 

Makes sense. Thx.

 

In light of the discussion around how much of the Z28's track performance is related to tires, I thought this bit about the Pirellis from the latest issue of C&D was interesting:

The Pirelli P-Zero Trofeo R's are essentially street-legal racing tires so tacky that, during development testing, they occasionally stuck to the pavement better than to the wheels they were mounted on. To keep the Pirellis from slipping around the rim, the wheels on production Z28's are media-blasted to increase friction at the mating surface, a common practice in racing.

 

Nothing new. Happens a lot with MPSC's on GT3's as well.

 

Correct, and MPSC were used in actual PCA club racing not too long ago. And shaved, were not too much slower than R6's.

 

Exactly. I'm not buying into the "z/28 has better tires" argument. MPSC are track day R comp tires, just like the trofeo R. Let call it like it is: the z/28 is impressively fast. Don't expect to be faster than a z/28 on track with a GT3, regardless of tire, because it will come down to the driver. I'm still getting a GT3...

 

Not suggesting the tires are a big deal, just thought the C&D info on the tires was relevant to the discussion. The Autoweek article at the top of this thread mentioned that the MPSC's were more "street oriented" than the Trofeo R's and Andy Pilgrim stated that the Porsche suffered some in comparison to the Z-28 due to "tread squirm" but no doubt I misinterpreted that and the tire difference really didn't matter. Apparently it only really mattered in the earlier EVO GT3 test when the Porsche posted faster times than the MP-4 on different tires. I get it....

 

Perhaps the MPSC aren't as sticky as the trofeo Rs, but they are still track day tires. MPSC are not street tires.

 

I know Joe. I've owned several sets of the MPSC's. The quote from Autoweek was that they were more street oriented than the Trofeo's. I think that's probably a fair description.

 

So how much of a time difference is there between a DOT approved track day tire and a DOT approved track day tire that is more 'street orientated'?

Would you agree that the time difference is not going to be huge (ie 2 seconds)?

 

Agree, the difference is very likely not going to be 2 seconds. OTOH, I'm willing to bet there won't be "no difference" between the MPSC and the Trofeo R either, and the Autoweek article and the quote from Andy Pilgrim seem to suggest that. As to the exact amount of difference, it would depend on the car, the driver, and the track, and lacking any direct comparison between a 991 GT3 wearing Pirellis and a Z28 with Michelins we can't know.

 

Porsche apologists gamely grasp at tire straws when the real issue is:

1. Why did Porsche never fix the tire rotation problem? As Nizer notes, it happens to GT3s. It took the aftermarket in the form of Ray's Volk Racing wheels (from Japan!) to deal with the problem via knurled bead seats on their wheels specific to GT3 centerlock fitment. Chevy identified the problem and fixed it for the Z/28. However, Porsche- "Posing not racing" once again shows as the reality, they could give a sh*t about owners driving home on square wheels.

2. Since tires and wheels were brought up, let's talk about more marketing over substance and the idiotic and dangerous centerlock wheel securing method. I spent a fun 5 hours yesterday right seating for a friend who bought a .2 GT3RS, and all I could think of was "is a wheel going to come off?" Because the support crew there knows nothing about how to properly service centerlocks (and were torquing the nuts with car on the ground). The poison gift that keeps f'ing giving into the 991 series because all 991 owners will be facing the same problem of (im)proper maintenance.

Attempting to shift the focus by making excuses about different tires is to deny the basic failures Porsche has made and continues to make. Those with open eyes and minds recognize and appreciate solution-oriented enthusiast engineering as demonstrated on the Z/28. The facts are undeniable and the results are there in lap times and everyday practicality.

 

shots fired!

I completely agree w/ you on the PITA CLs.