MaxLTV

I tried RE71R tires on a GT3 back-to-back same day, same car. The RE71Rs were 254 front and 295 rears because 305 is not available. Unfortunately, it was on a rainy day, so lap time comparisons are not possible. But here are some early impressions. My car is set up for oversteer to begin with (medium front, stiff rear on roll bars, and -3 front -2.5 rear camber), so that might have played a role as well.

1. Rear tire is way too stretched. Not to the point where it would be dangerous for tire placement on the rim, but to the point where sidewalls are pulling the shoulders in, making the profile of the tire more round, a bit like a motorcycle tire. I think that's why it does not work quite right.

2. Porsche traction control and stability system definitely has some adaptation to the tire diameters. I changed tires between sessions and got right onto the track. My first session out after changing the tires the traction control was cutting power when going straight in 4th gear... I was not brave enough to drive sonoma with a mix off dry track and standing water with all nannies off. Orthojoe did not have this issue, so I had hope that it would go away with some adaptation. Next session after that it was gone. So the car needs to be driven after tire change for the system to adapt. I think it's great news. Older systems would just freak out and not work.

Once everything got adjusted, the car would drive very well. Front end got better feel and wider sweet spot than with MPSC2. I'm not sure if absolute grip improved but it's definitely easier to make good use of all the available grip with these tires. Rear definitely felt lacking in grip, so the car oversteered way too much. But the oversteer was very predictable - this tire starts to side slightly before it loses much grip. This behavior makes both oversteer and understeer more predictable and easier to correct. It's also easy to keep the car in the zone where it slides slightly but not to the point where grip is compromised. And that's where you want to be for fastest and safest driving.

After two semi-dry and two wet sessions, front tires looked barely used and rears lost about 1/3 of tread - another testament to how bad oversteer was. I was within 2 seconds of my personal best on MPSC2, which I thought was great given that the track was still very wet in several critical areas.

Few negatives - tires definitely get more upset by bumps on the track. T9 feels like offroading.

In general, I probably will not get a second set in these sizes. I am debating getting 19" wheels and right-sized RE71Rs or just going with MPSC2s for now. Although these tires run narrower than N-spec MPSC2s with the same width number, so I'd love to have these tires in 265/35-R20 and 325/30-R20 sizes - these would definitely fit and be fine on stock wheels.

We should petition Bridgestone to make them in the right sizes - that would be useful for all the 991 911s, not just GT3s, so the market is pretty big.

TRAKCAR

What brand is RE71R

MaxLTV

Bridgestone RE71R

TRAKCAR

Thanks. Sorry could have Googled it.

s4corrado996tt

Tks for sharing!

stuntman

Thanks for the update. I had a feeling the rears would cause problems since as I said on your other thread:

Even with a narrower wheel, you're dealing with a ~10% reduction in rear width. I would have softened the rear bar when you ran the 71Rs but even then, width (and volume) is width (and volume) and the 71Rs are significantly smaller...

golfnutintib

hopefully b stone will make proper 991 gt3 rear size soon

it is a truly great tire... on top of the cost and wear benefits over cup 2 it feels better too