CincyScott

Have any of you guys considered TPC’s Tractive DDAs? Seems like if you’re putting that much into suspension and tire mods these might be an option. They have me very curious when I go to do suspension.

I had a set of PSS9s on a 996tt that I hated, but had a friend install PSS10s on his 997tt and they were brilliant. I got the 996 with the 9s alread installed, so I have no idea if they were revalved or resprung, but they were brutal.

Pdtp#16

They are fantastic and worth every penny. Also if you plan on using them on a 991TT/TTS, Mike can share with you his personal file on his track car.

Bruce H.

Randy or others with GT2RS experience...

A track buddy bought a lightly used '18 GT2RS and tracked it for the first time 2 days last week. He found the torque was over-powering the rear Sport Cup 2's (not Cup 2R), the traction control light was flickering constantly, the rear came out frequently and the throttle was too sensitive to prevent the wheel spin. The car also felt very light above 150 mph, lacking down force and was unnerving. Hot pressures were 35f and 39r as he says is recommended. He has lots of experience in his ACR-E that feels glued to the track and was expecting something similar. Another track friend of his with a GT2RS and 918 Spider says his experience is the same with his...lack of rear grip.

I've seen a number of reviews and don't recall grip issues being mentioned. It's obvious that he should try the Cup 2R tire but is that likely the whole problem and the solution?

Bruce

longboarder

35/39 hot? Wow that could be the problem right there.

I dont have a 2RS, but I have a GT3 and Turbo S and come in when the Cup2's get any higher than 33f /32r. I usually go out 28/27 do a couple laps to 33/32 then bleed down again to 28/27 and they are usually good after that for a while.

I've have Cup2's in the mid 30's and yeah it was slippery.

Bruce H.

^ I thought 35/39 sounded too much also and will ask where that recommended pressure came from. Thank you.

Randyc151

Yeah, I come in to the pits if I hit 35psi front or back. I go out cold at 26psi and creep around a lap or two (still faster than most people) until I get up to 30/30 and then let her rip. I don't have any issues with grip unless I am driving like a crazy green student. It's certainly tire pressure and driving technique - patience. When the car is straight, it bites like crazy. When exiting a turn, he needs to add throttle gradually until straight. Also possible he's entering turns to fast - slow in, fast out. If he needs more downforce, he needs to remove the grills under the fender vents, and change to the highest setting on the rear wing. Finally, maybe he needs to get the camber increased (more negative...you know what I mean). I just turned a whole mess of 1:56/1:57's at VIR this past week on sketchy Cup2R tires...I've never seen any street car do that, even on slicks. It's not a problem with the car, but maybe tire pressure, camber, and technique. He should really seek some coaching if these issues don't fix this experience. This is not meant to be critical, only constructive.

Bruce H.

Thanks Randy, all good suggestions. Have you only had the Cup 2R on the car or have you tried the regular Cup 2 on it as well? I suspect there could be a significant difference between the two. He's also considering swapping to Trofeo R's...thoughts?

Bruce

Randyc151

I've run both, and the Cup2R certainly has more grip than Cup2 for a couple of track days use, but it's not as dramatic as what those tire pressures would cause. No way any street tire is going to track well above 33psi. I have not tried Trofeo R's, but talking to Randy Pobst last week he does not think they stick quite as well as the 2R, and more in line with the 2. Bottom line, the tires themselves are not the issue here.

Bruce H.

Very good...thanks again! I'm passing on all the feedback.
Bruce

Pdtp#16

Randy, those are great times!!! I think its time you shared some videos! Love to see that beast on track.

Hope all is well

phangstaz

Has anyone experienced any gearbox/differential overheat? how many laps would it do before needing a cool down lap? (depending on race track layout of course)

miky360

I was lapping for about 30mins straight, basically till I ran out of fuel and I didn’t have one hiccup. I’m also doing 750hp so max strain on the gearbox. This was at Toronto Motorsport’s Park, Cayuga. I love Porsche

Randyc151

Well since you asked, here's my personal best lap at VIR from this weekend. Try not to notice that I'm running down an IMSA Daytona Prototype...


BTW, Pdtp#16, I noticed I'm also wearing my green t-shirt from my previous visit to Sebring. Coincidence??

TooTurbos

Hauling the mail for sure....Nicely done.

Think you could close in on the ZR1 time of 1:51.25 with a 100 hp deficit? I know thats asking a lot, more curious.

Randyc151

I have not personally seen a ZR1 do anything near 1:51, but I'd suspect it was on slicks to do that time. Certainly there are places I can go faster: 1) exiting turn 1, can get to full throttle sooner, 2) entering turn 2 I could stay on full power a tad longer (106mph) 3) between 4b and 5a I should have been on more power, 4) I could have stayed on more power up the climbing esses and entered 10 with more steam, 5) a cut too much speed in Oak Tree this lap, and 6) I could have entered Hogpen with less braking and/or on the power a tad sooner.
All of those things combined, on sketchy Cup2R rubber, I still am not sure I'm a good enough driver to do 1:51 with any level of safety. In a street car, my own street car, I am OK leaving a little room for safety.