tasman

Congrats. Still waiting my allocation. Enjoy her and keep us updated.

Mvez

My shop (Winning Formula) talked to Forgeline, and said they don't really have any clue. Their sales guys said they have a wheel fitment, but they don't. They were not even aware of the toe-link issue.

My guys have already bolted up a 19x11 wheel, and the issue is that the toe link will be too close to the inside of a 19"x11" wheel, with stock offsets, unless you run a spacer which means the wheel will then be sticking outside the wheel well, unless your run alot of rear camber. So, unless you shim it a lot, the head of the toe link is going to be a problem.

The good news is that apparently in order to run more camber (and adjust toe), you MUST run Cup toe links (or aftermarket) to adjust toe correctly, so assuming a spherical end will be smaller than the head on the stock toe link, then this will allow for more room to clear 19x11" wheels with stock offsets.

The other obvious fix is to simply run a 19"x10.5" rear wheel with an appropriate offset, which a 295 size will still fit on fine. The point is, the 11" wheel with 295 tire is shoe-horned in this car, and unless you run a very low profile 19" tire, I don't really see you getting much more tire than a 295. I'm sure a 315-30-19 can be made to fit, but it will require an 11" wheel for sure, and will still need to address the issues Aaron has found.

Let's face it, it's a cayman, not a 911, so it doesn't require a ton of rear tire.

I'm not even tracking mine, but I want to run some 19" E88 wheels, and Michelin sells a PSS tire in the perfect 245-40-19 and 295-35-19 size, which matches stock diameter identically, so I plan to find some wheels that will fit and still allow me to run these size tires.

ShakeNBake

In the end, all I care about is getting R7s on it. Really interesting news on the interference.

Mvez

Hoosier makes a 295-35-19, so you guys need to start asking Hoosier to make a 245-40-19, which will keep ride height exactly the same, rolling diameter identical front and rear, and then you can use it on any combination of 19" wheels for the track.

245 fits on 8.5 and 9" wheels perfectly
295 fits on 10"-11" just fine. Ideal width for 295 is 10.5", and what is used to measure most 295 size tires.

Porsche loves stretching tires on bigger wheels. In reality, this car can use a 10.5-11" rear wheel, using a 295 just fine.

fishing

I was thinking the same. It already understeers per Nur93's and Chris Harris. I'ld be more interested in changing tire/wheel dimensions and settings in the front. Correct me if I am wrong.

DeerHunter

All else being equal, a wider wheel will allow the tire to work better. I understand that a narrower wheel might be a necessary compromise, but it would certainly be ideal to keep the 11" width.

usctrojanGT3

Is a 9 inch wheel the widest you can throw in the front for a 19 inch wheel?

Mvez

Bar settings and alignment can easily dial out any understeer you want. Just like the 997 GT3/RS....you can throw more rear tire at the car, but then you lose the balance. The 7.1RS was perfect with a 245/305 combo.

I'd be focusing on getting a tire setup that keeps the rolling diameter the same, such as a 245-40-19 and 295-35-19, which gives you more options for suspension setup without losing 1" of ride height on tires alone, instead of trying to stuff as much tire under the car. Just my opinion.

I agree, and think a 19x11" wheel fitment can be had.

TRAKCAR

OK, now that you are done playing with it, send it to me so I can fiddle with it.

997rs4.0

I drove the gt4 for the first time today. Only on the street and a bit of traffic so hard to say anything about the chassi.
But just like previous posts the clutch is very light and suitable for DD. Gearbox felt nice and tight. LWB are very comfortable. Very easy to live with on a day to day basis. Overall I'm very impressed with the whole package. Power wise it felt very similar to 996gt3. The auto blipping will take a little time to get used to, found myself blipping at the same time as the car does it. Can't wait to try one on track.

Mvez

Not sure, maybe 9.5, but no real need for anything bigger than 9" wheel to be honest. Forgeline drove down and test fitted some GA1R's on my car today. The 9" had good clearance. I can't remember the offset, but they have the info now. It was more aggressive, and you'd want more camber for that more aggressive offset. You could go higher offset with 9" for less agrressive, or 8.5" with stock offset or a little lower (~55-ish) to get wider stance and more caliper clearance.

They also test fitted an 11" wheel, with about a 44 offset. It works, but barely clears the toe link and gives decent upper shock clearance. This fitment is for the "track/race" setup where more rear camber is needed, as the wheel does stick out a little further with stock camber.

A 10.5" ET44 is still going to be the no-nonsense, great clearance everywhere, no extreme camber needed, rear wheel size for 19".

LOL, I haven't even bounced it off the limiter yet I've got 150 miles on it, I said I would be nice to it until 200 miles, then hammer down.

ShakeNBake

This is a great service to this community to be pushing hard on finding out what's possible for wheel fitment - thanks Mvez.

TRAKCAR

+1 i hope we can get NT-01 work

Mvez

You guys need to start bugging Nitto for a 245-40-19 and 295-35-19.....like I did for the 305-35-18.

Rovman

Thanks for helping get some of these questions answered Mvez. Much appreciated!