strandolph

I ordered some 19" Supercar3's in December from Tire Rack. They still don't know when they'll be in stock.

YoshiKK

I concur with your view of R888R - they are not grippy. I felt I wasted my track day with these tires.

jwr9152

I've recently run Supercar 3 and like them. Similar grip to an RE71R with better wear. I'm currently running Falken RT660 and like them a lot. More grip and faster then the RE71R or Supercar 3. Wear rate seems similar to RE71R, but do seem to like a little higher pressure.

ZG911

What size tires and what wheels (size and brand) are you running? I am currently running 165/35/19, 285/35/19 on Forgeline 9" and 11" width..

jwr9152

I have a 718 GT4 and have run the Supercar 3 in 245/35/19 and 295/30/19 and 265/35/19 and 305/30/19. The Falkens in 265/35/19 and 305/30/19. I ran the 265/305 on Forgeline 9x19 and 11x19. The 245/295 I ran on OZ 8.5x19 and 11x19.

jreifler

This shouldn't happen. I run 19" slicks and there's a constant TPMS light, but that's it.

That said, I have had this issue once before when I had to swap front slicks mid-weekend after one shredded. The overall front diameter of the "replacement" fronts was a good bit taller than my normal setup, and I did get serious interference with TC / ESC on. Limp mode as well.

Measure your actual diameters front to rear. They should be as close to the stock measurements as possible (even adjusting for 19" wheels). If you deviate significantly front to rear from stock, I suspect that's what causes what you described.

BUT, if those are your actual sizes, the front and rear diameter are supposedly both 26.3". Stock Michelins are 26.8". So you should have been fine. Positive about the tire sizing ? I'm sure you are . . .

Edit - Don't rely on TPMS at all for monitoring or measuring tire pressure or temp at the track. Ignore it. A solid gauge and temp probe are critical for accurate track readings.

jreifler

I've run this size and 295/35 rear R7s for a couple years now, No issues at all. The larger rears do rub the inner wheel well ever so slightly under really heavy force.

m3bs

I’ve done several track days at two different tracks since I posted that. Each time I had similar intervention until the tires got warm. Once they warm up I have no problem, no intervention unless I really deserve it….. I switched from SC3R to Falken RT660 for most recent day, and still had minor issues the first lap, but after that it was good. I still had limp mode issues, but that was triggered while going straight at 7K. New CPS is on the way to address that. I hope….

I did have a U0418 code stored, for which my Foxwell scanner simply said “check PSM control unit fault memory”. I recently picked up an Icarsoft POR V3.0, and it showed the same code with the description “Invalid data received from brake control module”. Sounds like that could be related, but not definitive, at least to this layman.

I may try starting out with tire pressures biased to get the diameters closer to the stock ratio. If the problem goes away, at least I’ll know that’s what the cause is. I have been starting out with equal cold pressures front and rear (28 psi).

TRAKCAR

If it’s like in the 991.2RS if they drop under 26 and you don’t “set” it to track before you move the car it won’t take. If you then want to use TPS you have to inflate above 26 and start over. PITA. I use a gauge but on track I need it to have the confidence all tires are where they’re supposed to be. And still I’d never run Hoosiers.

On the SC, maybe you didn’t give it enough time with Nannie’s on? I have no GT4 experience but in the RS it took 3-4 laps for SC to like 19” that had slightly different outer diameters, but within range of a couple % difference front to rear..

jreifler

Really sorry to hear you're struggling with that. It's never once been an issue for me. Have you called up any of the GT4 race gurus (e.g. BGB) to see if they've experienced this or have some better insight ? I think you'd have to be fairly far from the stock tire diameter, or have a F-R diameter mismatch, to confuse the ECU enough to trigger your symptoms. Very odd.

Five12Free

I go even lower then those cold pressures with my remaining RE71Rs. I usually go out at 25 or 26 PSI cold which gets me to about 32 hot. No faults or warnings. Always with track pressures mode enabled.

Phokaioglaukos

Been using RE-71Rs in front 265/35R19, rear 285/35R19 on the 981 GT4 and am looking for recommended replacements now. Supercar 3s seem to be available but not 3Rs. Any help?

CyberGeorge

https://www.tires-easy.com

I just bought a 245/35R19 and 305/30R19 Supercar 3R. Got in 2 days and less than the rack…

paffinity

Not the most ideal sizes unfortunately. I've been on the waiting list on TireRack for 265/285 3R for about 5 months now. Just have to wait I guess.

Phokaioglaukos, I recommend you try the Supercar3. They are similar to RE71R but definitely last longer. The current set I have is on its 10th day without losing much time at all.

CyberGeorge

Agreed on the super car 3. That’s what I was using continuously after the RE-71R. Understood about the sizes as well, but I’ve played around with different sizes and with the 245-305 I’m actually o/s in my setup. I prefer a bit of o/s vs u/s but if I go to 265, it’ll be worse. The 245 bites really hard in the R compound and I’m actually wearing the rears quicker for the first time. R compound gave me 1 sec in a 1.8 mile track but I was happy with just the 3s. Hoosiers were the same for me, but they’re finicky with getting them to ideal temp and cycling. I’m running -3 front, -2.8 rear and medium front, hard rear sway. I’m actually going back to medium rear to fix o/s a bit.

But very happy with the supercars and I loved the RE-71R. I don’t think I’m missing anything and they last longer. R is definitely stickier in the dry, won’t last as long, but about the same or a little more than RE-71R.

My info says tire rack will get the 265R in June.