Wheel issues

[jcslocum]

First of all, the Box was not designed to have the same sized tire at all 4 corners. It's designed to have a stagger, front to back. This is the info I found for stock wheels:

WHEEL SIZE FRONT16 x 6
WHEEL SIZE REAR16 x 7
TIRE SIZE FRONT205/55ZR-16
TIRE SIZE REAR225/50ZR-16

And for the "S" which is a quite common upgrade on the base:

WHEEL SIZE FRONT17 x 7
WHEEL SIZE REAR17 x 8.5
TIRE SIZE FRONT205/50ZR-17
TIRE SIZE REAR255/40ZR-17

Many upgrade the fronts on the Box to a 225/45-17 to give a little bit better balance but it stays on the 7" wide wheel/rim.

I'm sure you're rubbing up front like crazy and the handling has to be a bit out of whack and could be a bit dangerous with this set up. The balance of the chassis is all out. If I were you I would change the fronts to a proper width 19" tire.

Tire rack has this as the 19" option for the 2000:


CONTINENTAL EXTREMECONTACT DW
Max Performance Summer
Front: 225/35ZR19 88Y XL
8.5" wheel

Rear: 265/30ZR19 93Y XL
Sidewall Style: Blackwall
10" wheel


So, even in a 19" wheel size, you stick with the 225 width. The wheel size is also still staggered. You have too wide a tire and probably too wide a wheel up front.

[JayG]

Originally Posted by jcslocum

First of all, the Box was not designed to have the same sized tire at all 4 corners. It's designed to have a stagger, front to back. This is the info I found for stock wheels:

WHEEL SIZE FRONT16 x 6
WHEEL SIZE REAR16 x 7
TIRE SIZE FRONT205/55ZR-16
TIRE SIZE REAR225/50ZR-16

And for the "S" which is a quite common upgrade on the base:

WHEEL SIZE FRONT17 x 7
WHEEL SIZE REAR17 x 8.5
TIRE SIZE FRONT205/50ZR-17
TIRE SIZE REAR255/40ZR-17

Many upgrade the fronts on the Box to a 225/45-17 to give a little bit better balance but it stays on the 7" wide wheel/rim.

I'm sure you're rubbing up front like crazy and the handling has to be a bit out of whack and could be a bit dangerous with this set up. The balance of the chassis is all out. If I were you I would change the fronts to a proper width 19" tire.

Tire rack has this as the 19" option for the 2000:


CONTINENTAL EXTREMECONTACT DW
Max Performance Summer
Front: 225/35ZR19 88Y XL
8.5" wheel

Rear: 265/30ZR19 93Y XL
Sidewall Style: Blackwall
10" wheel


So, even in a 19" wheel size, you stick with the 225 width. The wheel size is also still staggered. You have too wide a tire and probably too wide a wheel up front.

Not sure if "designed" is the correct word. Many people for competition do run a square setup, all tires the same.

Tire and wheel size is just part of the equation, wheel offset plays a big part in what will fit and what will rub. Even a 16 or 17 with the wrong offset will rub

Also 18" wheels are a factory option as well, at least in later model years

For 17's, 225 front and 255 rear is better than the factory setup of 205/255

[thstone]

Originally Posted by jcslocum

First of all, the Box was not designed to have the same sized tire at all 4 corners. It's designed to have a stagger, front to back.

Yes and no.

Yes, the stock setup is staggered.

But no, the car is designed to accept a 8.5" wheel with a 255 width tire on the front without rubbing. Jay is correct that the racing guys do this all of the time without any problems.

The reason that the car doesn't come with a 255 square setup from the factory has to do with handling, not rubbing. The staggered setup creates significant understeer which Porsche feels is a safer handling characteristic than neutral or oversteer. A stock Boxster running 255 square tires with the factory sway bars will slide the rear end around like a drift car - but they won't rub. (Racers get the car back to neutral handling by using non-stock adjustable sway bars).

Thus, the likely problem is that the front wheels have the incorrect offset which is causing the 255 width tire to rub.