I've been trying to figure out the ideal spacer set up with stock turbo wheels. I originally went with the 7MM front 15MM rear and felt the rear tires were a bit too far out mainly the rear tires, made it look like an American muscle car. I then started to figure out what aftermarket wheel makers were doing, like HRE in terms of offset etc, even comparing the stock WB turbo with the 997.1 GT3RS WB which has a perfect stance and what I'm trying to acheive. Based on my research, the front wheels are the same size 8.5 wheel, with 3MM smaller offset on the GT3RS meaning the wheels are further out on the GT3RS. Also the rear tires are both 51MM on turbo and GT3RS but the turbo wheel is 11 inches vs. the GT3RS wheel at 12 inches. Given the tire size is the same at 305, the GT3RS is stretching the tire out. With the one inch larger rear rim, and same offset, this mean the inch is divided between the front and rear lip of the rim by half inch. This is 12.7MM or roughly the 15MM spacer I installed. The main thing I noticed was the stock potenzas have a substantial rim protector and obviously not stretched as much as a 12 inch rim, making the stock wheel tire combo appear wider than say a 305 on a 12inch wheel, which is more stretched at the edges.

Just curious if anyone has run a 295 tire (many non WB Carrera with 11 inch rim run this tire size) on a turbo OEM rim with a 15MM spacer to give it that just perfect stance. Since the tire will be pulled due to the smaller tire, it might be equivalent to a 305 on a 12 inch wheel.

In the end due to the lack of spacers larger than 7 and smaller than 15MM, I might just run 3MM up front and 7 rear for a mild stance improvement.

Anyone with HRE wheels measure on their offset with 8.5x19 and 12x19 on 997.1 turbo? Just curious if its much different from a 997.1 GT3RS.

 

first there are those, me included, that a 305 section tire is too small for a 12inch rim. I dont know why P doesnt just use 325's like the GT2 RS.

also, if you go to down to 295's how will it effect the height? As you know the F/R difference should be constant otherwise you risk damaging the diff.

3mm, can you tell ? i cant

Seems like you need custom spec wheels. GL.

 

i ran 295 on stock wheels for a while. No issue. Changed to 305, with 16mm spacers. But lowered the car. And thus changed the alignment. If your car is not dropped, what are the alignment specs? Making it a bit more aggressive camber wise will push the top of the tier a bit further in. 305s also are wider from brand to brand due to the rim protection as well...

 

Stock height at the moment. Really want to keep this as a functional dd, but it seems all the turbos that look proper have aftermarket wheels with smaller offsets and lowered.

Ordered 3 mm off eBay, will see, otherwise some lowering springs might be in order.