Recently picked up a used set of OZ Allegrittas in 18x8.5/18x12 with stock offsets for my 997.1 GT3. What 200tw tires would work best in Street class? The Bridgestones max out at 295/35s, which I assume are too narrow for the 12s? I think that leaves the RT660s and the A052s. Thinking maybe 255/35 in front and 315/30 in the rear? Planning on a fairly aggressive alignment. Also contemplating a shock upgrade (love the MCS 2WNRs on my S2000). Want to stay within SCCA Street class rule set though, which I think permits these wheels (I hope). Any suggestions on tire sizes? Thanks.

 

I've seen the 295/35 mounted on 12" wheels, it looks a little silly but the car owner said it worked well (not a Porsche). It's hard to say if it'll be worth giving up the 20+mm versus 315 a052s. Might depend on surface/conditions/how worn out your LSD is.

 

conners tried them on 18s on his 997.

 

I would start with 245/315 or 255/315 yoks, they will be the easiest to get your feet wet with. Keep an eye open for a set of 19s so you can try the Bridgestone 255/305 setup. Your differential will need to be absolutely fresh to make the Bridgestones make pace. The less we knew what we were doing with the car the softer front and stiffer we had the rear bars because I didn’t trust it trail braking. The faster we’ve gotten the softer the rear has ended up and the front has tended stiffer.

it’s still a good time to run XA with an older GT3. I suspect they will still be able to trophy at nats for a few more years. A tune, headers, and the RS ring and pinion make the car a monster on the street and autocrossing! super street would be an exceedingly difficult place to play with a vintage GT right now.

 

Thanks, all. I don’t really wanna go down the modification path with this car, and I know that this is not a competitive platform at the national level. Maybe I will sell the 18s and just put Bridgestones on the stock wheels. The car is not really a daily driver for me anyway. I seem to have a knack for owning cars that are cool cars to own, but not particularly competitive autocross cars (my STR S2000 is another example). Maybe it is because I tend to like older cars, and the newer cars are generally the most competitive in the relatively unmodified classes. It would be nice if the 997 GT3 were moved to A Street.

 

I don't think the GT3 ever moves to AS. Production numbers are too low and the cost is too high. The 981 GT4 really should move to AS, but that also probably will never happen (despite their desire to class an Evora with nearly identical specs). I would still recommend trying the Yoks first. Their ability to multi task makes the older GT3 much more approachable. When I first bought my GT3 I went straight to the Bridgestone of the time and the car was unwieldy enough that I thought I had made a mistake buying the car.

 

It's a Carrera S, but I agree on the approachability of the Yoks versus anything else I've had on the 997. With the camber of the GT3, you can make full use of them, too.

 

I am not following what you guys are saying is more approachable about the Yokohamas over the Bridgestones? I have the Bridgestones on my S2000 with a full Karcepts STR suspension. It is super easy to drive on the edge and inspires a lot of confidence. I like them better than the RT660s I’ve driven before. i have never driven on A052s. Can you explain what you mean?

 

We have RE71RSs on the GT3 and the GT4 at the moment. The cayman loves a super sharp tire. The GT3 was really hard to drive on a peaky tire. It's difficult to multi task, and for some reason the stone really struggles to put down power on my 997. If you're learning alignment, sway bar settings, and driving style for the 911 the Bridgestone was really hard to drive. Now, to be clear when I was starting with my car it was the old RE71R not RE71RS. I picked the RE71R when I bought my car because we had been driving them on a cayman, and they were an absolute riot. It was not a riot on the GT3. It was dicey, didn't multi task well, was not tolerant of being slid around. Very unforgiving trying to get that tire to do 911 things. I was coming from an air cooled 911, so I wasn't a stranger to rear engine platform. Starting on the RE71R was one of the biggest mistakes I made early on. On the GT3 I think the speed difference between the A052 and the RE71RS is in the noise. The A052 is easy to drive, puts power down like an absolute monster, and lights off immediately. It's going to invite you to play and move the car around some. It should be a much more effective "getting to know you tire".

 

Yeah kind of what he said. The ability to overlap inputs on the A052 is unmatched and it lets you dance with the rear of the car moving around without snapping on you. That little bit of sloppiness they have is actually a benefit on a more old school, short wheelbase 911 that needs the rotation driven by its major "flaw".

 

Got it. Thanks.

 

Basically, to get the 997 to slither, it's doing so partly via the rear engine pendulum. Yoks just feel like they give you more window to work with, and on slower corner exit, they just accentuate the traction the 997 has.

I have tried Bridgestone front and yok rear and the car was very difficult to drive quickly. Two events on that combination was enough to tell me. The front had RIGHT NOW response and grip, while the yok rear was still generating slip angle to get to its peak. The timing difference between when the front gripped to the rear did was...challenging.