Does anyone have experience with the following tires on a 996tt stock wheel. Hoosier R3s04 Front 245-40-18 and 305-30-18. These tires tend to be much wider than other tires in the same size. Any help would be appreciated.

 

Hi. I think you'd be making a mistake with those sizes.
The diameter of the front would be 24.5" and the rear
would be 25.6"! Your PSM and ABS would go nuts, not
to mention your viscous clutch. You want the Hoosier:

P245/35ZR-18
P285/30ZR-18

Not as wide as you'd want, at least in back, but the diameters
are right.
Joe

 

oops! Nevermind! I have old AS03 size specs there, not the new
AS04 specs which are different!

 

From the Hoosier site:
Wheel Widths
Wheel width dramatically affects wear and performance of the Hoosier P-Metric radial tires.

There is about a one inch window of optimum width. The trick is to figure out that window. A good rule of thumb to use for determining proper width is to use the tread width of the tire. Measure the tread width. Plus or minus 1/2 inch from the tread dimension will indicate the proper rim sizing. It is possible to use narrower wheels, but at a sacrifice to shoulder wear and cornering power.

"Measured" rim vs. "Recommended" rim
In our printed product catalog and on our website tire specifications you will see two columns of information regarding rim dimensions. In most cases, the "measured rim" and the "recommended rim" will be the same. However in the case of DOT tires, the information may appear contradictory.

The reason for the differences lies in the Department of Transportation requirements for publishing tire dimensions on any tire that carries a DOT certification. Each tire size has a specific rim that must be used when taking measurements for tire comparison. This is intended to allow consumers a consistent way to compare tire sizes between brands.

With respect to the Hoosier P-Metric line, the recommended rim size will typically be wider than the DOT standardized wheel.

The fact that a tire will "fit" on a rim is not an indication that it will work effectively in that condition. Radial tires are extremely sensitive to wheel widths. The performance characteristics of the tire can change significantly within the recommended range of application. Mounting a tire on a rim that is outside of the recommendation is not a good idea.

 

With that in mind, I think that Hoosier would recommend the
46810 P225/40ZR-18
46840 P285/30ZR-18

tires for our 8x18 and 11x18 wheels.
Joe