I am running 215/60/15H on the stock wheels on my 300E with Eibach/Bilstein upgrades. What tire pressure should I use for day-in day-out driving? Also, what's the verdict on the right way to rotate tires. I thought that rear wheel drive vehicles should only be rotated front to back (and not side to side). When reading Lee's comment (in Featured Car Feedback) regarding being able to rotate the Michelins more than the asymmetric Pirellis I began to wonder....

Any advice would be appreciated!

Nick,
There is nothing wrong with rotating front to back. However, once you wear out the outside shoulder of a tire front to rear rotation does not help anymore. In a situation like that you can dismount the tire from the rim and remount so that the worn shoulder is on the inside where it will accrue the least abuse. This also puts the fresh shoulder on the outside where it is needed. On an asymmetric tire, the inside shoulder is different from the outside shoulder and is not safe to put on the outside. This is keeping directional tires rotating their intended direction and only applies if both tire shoulders are identical. For those of us who might corner hard enough to wear out the shouder of a tire before the center tread this applies. For people who "drive miss daisy" the front to back rotation works fine.(most of the population) Front engine/rear drive cars tend to wear the outside shoudlers of their front tires and the middle or flat tread of their rear tires. That is why something like the Michelin may give you more miles because you can rotate them so that you wear out the whole tire, not just a area or two.

As far as what tire pressures to run on your car...that is somewhat subjective. Running recommended stock pressures (inside your gas cap) certainly wont hurt anything. More pressure will give better handling, sharper reflexes, and more ride impact. When adjusting the pressure up, keep the same pressure ratio as stock. Example: IF your car is supposed to run 29 font and 32 rear you can air up the back tires to their max psi (lets just say 44psi) and put the fronts at 39-40 lbs. Remember that cold psi is just that...cold. Measure first thing in the morning before you have even started the car. Just air the tires over where you want them the night before, park it overnight, then just adjust (by letting the air out) before you drive in the morning. That way you know that the pressures are accurate cold psi numbers.

Enjoy!...Lee