Air pressure

[Dlirium]

Originally Posted by Joe B

I have the same size rims. I like 30 F/34 R.

Joe - not to get off topic, but what are the rim sizes on your 18's?

thanks!

[kk2002s]

I have tried up and down, winter time summer time
I have settled on the recommend 29/36 on my 18" staggered.
Tires wearing evenly
+ psi harsher ride
- psi a bit squirmy

[lkchris]

It's my personal policy to never have less than 30 psi in any tire on any vehicle.

Therefore I do 30 and 36.

This said, there really is little reason to doubt the Porsche recommendation.

[mump]

Originally Posted by lkchris

It's my personal policy to never have less than 30 psi in any tire on any vehicle.

Therefore I do 30 and 36.

This said, there really is little reason to doubt the Porsche recommendation.

yup, 30/36 here.

[Joe B]

Originally Posted by Dlirium

Joe - not to get off topic, but what are the rim sizes on your 18's?

thanks!

Well, I know the rears are 18x10, and although I'm pretty sure the fronts are 18x8, I'm not near the car to check, and I'm not positive. 225/18 F and 265/18 R tires (I remember that much). They're the 996 Carrera 5-spokes, optional on the 2003 Boxster S.

[KRAM36]

Originally Posted by Joe B

Well, I know the rears are 18x10, and although I'm pretty sure the fronts are 18x8, I'm not near the car to check, and I'm not positive. 225/18 F and 265/18 R tires (I remember that much). They're the 996 Carrera 5-spokes, optional on the 2003 Boxster S.

Did your car come with those wheels or did you buy them and install them? For the Boxster the Carerra Light wheels are Fronts 18 x 7.5 Rears are 18 x 9. The size you posted are from the wheels used on the Carerra.

[Dlirium]

Originally Posted by KRAM36

Did your car come with those wheels or did you buy them and install them? For the Boxster the Carerra Light wheels are Fronts 18 x 7.5 Rears are 18 x 9. The size you posted are from the wheels used on the Carerra.

ah - that is what I was looking for. So 18" wheels on a Boxster as a factory option was 7.5" wide in front and 9" wide in back...great!

I'm trying to figure out if my wheels on my 2000 S are stock or not!!

[thstone]

The stock tire pressures were defined to ensure that the car has understeer and not oversteer. This is also the reason for the staggered tire widths (narrow in front, wider in rear).

Thus, generally the goal of tire pressure changes to a stock Boxster is to decrease the amount of understeer inherent in the design. To achieve this, slightly increase the front pressure and decrease the rear pressure. 31 front and 33 rear is a good starting point.