According to standards published by TUV Rheinland in Germany, the correct load rating for the Porsche 997 (slight variances among models) is 450Kg in front and 635Kg in the rear.
Be aware that the TUV cornering fatigue test is at much higher stress loads than the SAE or JWL requirements. Therefore, the standards are not comparable.

All of our Tech1 wheels meet the stringent TUV standard. ALL.

 

Nearly 40 track days on my OZ Allegeritas - 8.5 x 18 F, 12 x 18 R. No problems even banging curbs to shortcut some apexes. Tires seem to stay put, friends with CCWs frequently complain about tires spinning on the wheels - they try hairspray etc.

Each wheel comes with a weight sticker, mine came in at 18 lbs. F, 22 lbs. rear - pretty light.

These wheels have passsed TUV according to OZ & Tire Rack sites.

I have been pleased with the wheels.

 

to have 8.5" in front with 12" in rear is not really quite optimal as if 12" rear rim can take 335mm rubber then front will want 255 or 265 tires and 8.5" rims is not wide enough for that.
9" and 12" combo makes much more practical sense. 8.5" goes together with 11" rear and works for 245/305 tires.

 

right on.
what wheel you run depends on what tires you plan to put on.
for example on 6gt3, if your run mspc, you dont do 12" rear.
if you run hoosier then 12" is better than 11".
it's ALL A SYSTEM, that's why some ppl have 3,4, 5 sets of wheels.

 

Interesting, you might want to measure some different manufacturers wheels and tires before giving such definitive advice. Having compared wheels side by side without tires mounted and tires side by side mounted and unmounted, I can tell you one manufacturers 8.5" is identical in width to another manufacturers 9" wheel in width. Similarly, Hoosier 245 R6's are same tread width as some other 255s.

I have 3 sets of these wheels, 2 sets with R6s 245/35 & 315/30 and 1 set with Wets. If I made a mistake, I haven't noticed it in handling or lap times. I have been extremely pleased with both the wheels and the tire setup. It is good not to know any better I guess.

 

OEM is 8.5 and 12 with 235 and 305. I would think that 245 and 305 would not be out of line for the same size wheels.

 

well, i`ve seen some modded cars to run 10" fronts and 12" rears. 8.5" stock front limitation is quite artificial and imho 8.5-12 it is a too much of a gap, imho 2" split between front and rear rim width is somewhat optimal and i would prefer to run 10-12 than 9-12 if I had such a choice. or at least 9.5 which would work better with 265 tires.

when you rotate upper gt3 mount for more camber rim will dive inside a bit and my 9" ccw rim is completely /inside behind the fender now. so I do see 10" rim can fit there as well - it will fit exactly as my 9" rims were before on stock C2 upper mounts before with tire`s edges in line vertically with fender`s edge.

to run 245/305 or 255/315 or 265/335 is a personal choice question but i can say I love the feel of my 265/335 with square shoulders right now. it is very stable and for auto-x wider is always better.

 

my rims are
ccw c14 -
18x9 +50mm (7" backspace), 18x12 +69mm (9.25" backspace).

and measured inside width is exactly 9". i used to have OZs in 19" and they were close to 9" when measured for outside edges but inside width was 8.5". So not sure how it can be so for 8.5 be equal to 9".

 

sweet

 

^^ Thanks for contributing.

 

The Turbo is a 997, and the GT3 is really just a C2S (Mobonic before the wrap), not that this really matters.

I have a set of Volk TE37, very light weight, good prices lately, and very durable. Not the nicest looking wheel IMO, but does the job for the track.