Guest89

Should not kick in at reasonable street speeds; I've never had SC kick in on the street, TC only occasionally (worn tires, wet, etc.).

If you're contemplating the purchase of a car with old AND mismatched tires, insist that the seller fit new Michelin Pilot Sport Cup 2 tires.

Who in the world would mismatch tires on a $200k+ GT3 RS?

r6elmo

I've rarely felt my TC come on on the street. Recently had the car at a car wash and they decided to armor all my tires and got some on the tread. First drive off the lot the tires spin a bit, but the throttle just goes to 0 and you see a blinking light and bam on your way...no chatter of rear brakes in this case.

Larry Cable

+1

andrew2008

This happens on my 2010 GT3 unless I use N-rated tires. I think the
threshold for activating SC is too low. Maybe some cars are more
sensitive since some people see a problem and others don't.

FLT6SPD

Could the wiggle be contributed to the stock diff? Has anyone noticed any wiggle when going to a Guard diff.?

Tim Kay

Owner punctured one rear MPSC and believe it or not the receipt of the Bridgestone replacement tires indicate the purchase and mounting was provided by the owners Porsche dealer! Owner didn't want to pay the price for new MPSC's.

Is the "threshold" programmable or calibrated by the dealer? If so, is it necessary when changing a brand of tire or a different diameter tire? Why do you think an N-rated tire makes a difference?

I don't think so, the issue does not exist with the TC-SC turned off. And when I say "wiggle" it's more like a feeling of the brake tapping on in one corner of the car rather that equal from side to side.

BTW, when the issue occurs there are no dash warning lights. I'm not buying the car, I'm only trying to help the owner diagnose the issue.

andrew2008

As far as I know this is not something that can be programmed or calibrated by the dealer.

With N-rated tires I don't feel the "wiggle" but with non-N-rated tires I do.

Guest89

Very distressing; arguably the most important part of the car. What bridgestone provides the appropriate rear fitment? It's a 325 section IIRC.

ZMC-ZH

Got the same experience on my vanilla GT3 on MPSS and proper alignement. There are 4 things to do after starting the car
- Sport mode button
- TC off
- SC off
- Clear warning message on the obc 😃

Since I apply this procedure VERY carefully, I have not experienced it on the RS

Larry Cable

NUTS!

its not AFIAK, in my mind putting the car on the same rubber, N rated or not, should resolve the problem!

change the tires ... its ridiculous that a $150k plus sports car is running on mismatched rubber for the sake of price!

change the rubber to be the same all round, that should cure this; if you think about this, you have different tires F/R which is impacting the relative
slip angles which the TC+SC is detecting and intervening.

charles06

I've had this EXACT SAME issue with my 2011 GT3. Tires are Michelin Super Sports. Been driving me nuts for years! And needless to say, it has scared the $hit out of me a few too many times.

Took it to local Orlando dealer...no luck.

Sent it to Champions...no luck. (Awesome guys, btw!)

Took it locally to Rum Bum Racing...no luck. (Also awesome guys!) However, their theory is that the yaw control sensor is out of wack, causing the computer to apply the brakes. They and I sat in their garage going back and forth over possibilities, but at the end of the day, we decided it can't be something mechanical as it completely goes away with the push of a button, meaning electrical. Keep in mind that I had my car at Champions for over a month, checking brakes, hubs, alignment, suspension bits, wheels, etc. Currently waiting for Rum Bum's (outsourced) guy to check it.

For now, I turn off the SC and it's all good.

ChrisF

Tires and maybe alignment. As most have said, it's crazy someone skimped on this car. Not a good indicator. Hard to tell if there's a bigger problem with tires exacerbating it.