sasilverbullet

Please specify:
1. Year/model of car
2. Exact wheel size/make, and exact tire make/size.
3. Also, some words on why you use what you do?

Thanks!

Robert Nixon

1. Year/model of car: 2009 base Cayman
2. Exact wheel size/make, and exact tire make/size.: OZ 18 inch/stock 235/265/Yokohama A052
3. Also, some words on why you use what you do?:
I've had the car 3 years, have done track days and autocross on
---a set of Hankook RS4s, great and long lasting.
--a set of Falken Azenis RT660 tires, autocross only, gave me my best results ever, had to go 235/255, couldn't find 265 in back. Maybe not relative, but had a slow leak after say 4,000 miles or so.
--just bought the A052s just because they were the rage a few years ago and I never found them in stock, haven't competed on them yet.

vitaminC

Already sent you some of this in a PM, but here it is again.

Car:
2005 Boxster S

Wheels:
front- 18x9" ET46 APEX SM-10
rear- 18x10" ET36 APEX SM-10

Tires:
Nankang CR-S 245/40/18 front, 275/40/18 rear

The challenge is finding a rear tire with a 40 aspect ratio instead of 35.

Apex has a nice collection of wheel fitment guides with tire suggestions for many size and use combinations.

Aussie skypig

Is there a “decode” for BBS wheels?

Can I easily measure the “rated” width of the wheels fitted to my Cayman S? (I’d imagine to the nearest 1/2” would tell the story)
The rears seem 11.5” from outer edge to outer edge. I’m told they are 9.5” (1/2” wider than stock 987.1 S)

Cast into the rims:
”Made in Germany”
Front - KBA 49674
Rear - KBA 49673
Does this mean anything to do with size/construction? I assume these wheels are cast, not forged?

vitaminC

Google is a good decoder Oh, and you can also typically find the size and offset info stamped onto the wheel itself somewhere.

From this thread:

Aussie skypig

Thanks for the link.

I tried Google, but failed so far.

Zipper8650

are you on the new version of the CRS? I am currently on the fence with getting them or the rt660s for next season. I was one of the few people last season not on 200tw tires

vitaminC

I have the old version. I don't have any other 200TW experience beyond that set. Unsurprisingly, they were light years ahead of the 340TW tires I was running on the OEM wheels. I'll probably get the new version when it's time for replacement if only because options are limited in the rear 275/40/18 size.

Zipper8650

[QUOTE=vitaminC;19131795]Already sent you some of this in a PM, but here it is again.

Car:
2005 Boxster S

Wheels:
front- 18x9" ET46 APEX SM-10
rear- 18x10" ET36 APEX SM-10

Tires:
Nankang CR-S 245/40/18 front, 275/40/18 rear

The challenge is finding a rear tire with a 40 aspect ratio instead of 35.

Apex has a nice collection of wheel fitment guides with tire suggestions for many size and use combinations.[/QUOTE

Hey, pretty set on the CR-S V2s for next season on 18 inch rims. The shop Im using offers 35 and 40 for the rear. The fronts will be 40s...what is the draw back and or advantage to running 2 different ratios?

thanks!

vitaminC

The 275/35/18 rear is about 1” smaller diameter. So you’ll be turning more RPM at speed and accelerate a bit faster as well. And probably have some extra fender gap. You can get the Nankang In 275/40/18 from tire rack or Phil’s.

Zipper8650

Appreciate the response! I am going to use Phil, he came highly recommended by my indy shop.

So I acknowledge that Im nitpicking here but im debating 2 theorys:
A - go with 40s all around, factory engineers know better and with a little bigger tire in the rear possible a nose forward rack?? i am not convinced of that last part
b - go with 35 in the rear to benefit from acceleration, these are going to be dedicated autocross tire with a possible couple of DE event on track

thanks!!

vitaminC

I’ve been having the same debate with myself on tire size. For now I plan to stick with the 40, though in the future I may mix it up. Especially if I get coil overs and can adjust the height down a bit. If you get 35s let us know how it goes!