[Nat Brown]

So there's no one answer, there's tire pressure for daily driving (comfy, yet sporty), for performance driving, like Autocross, and maybe even modfications based on road conditions, such as another preference for wet weather.

To be honest, I have yet to even check my tire pressure, but I know it's time, since I've had the car in the states for about a month now. Any recommendation for a 330i with Sport Package for a comfortable, yet firm daily ride? I've got 225/45ZR17's in front and 245/40ZR17's in the rear. Max pressure is listed as 30/35, although I know people go higher for sportier driving.

Better yet, some tire pressure guidelines would be useful.

--gary

 

[alee]

Tune it to your own tastes

I run 34F/35R. That gives a mild understeer, and sufficient inflation to protect the rims against potholes.

Too much inflation will risk compromising the tire when hitting a pothole. Too little inflation will risk compromising the rim when hitting a pothole.

Adding extra inflation may also make the ride choppy, so experiment a little. 34F/35R is my favorite setting. I check it at least twice a week.

 

[ObD]

I check it at least twice a week.

You're slipping, I'd expect at least twice a day. :angel:

 

[alee]

You're slipping, I'd expect at least twice a day. :angel:

LOL! I recently started carrying disposable latex gloves in my car to keep my hands clean when I clean the wheels or check the tire pressure. I figure that's obsessive enough. :tsk:

 

[Nick325xiT 5spd]

I suggest higher in front. I run between 38 and 44 in front, and 33-36 in back. It cuts WAAAYYYY down on understeer and makes the car a lot more fun.

 

[alee]

I suggest higher in front. I run between 38 and 44 in front, and 33-36 in back. It cuts WAAAYYYY down on understeer and makes the car a lot more fun.

I'd imagine those would be pretty nice track pressures. I tried boosting my front once, and it was way inappropriate for regular day-to-day driving.

But then again, my brakes are still good after 14k miles, and I still get 24mpg.

 

[Alex Baumann]

LOL! I recently started carrying disposable latex gloves in my car to keep my hands clean when I clean the wheels or check the tire pressure. I figure that's obsessive enough. :tsk:

Gee ! I bought a 25er pack on last Friday

No Al, nothing wrong with that, hehe.

 

[alee]

One other thing to note...

Maybe it's because of my first experience with low profile tires, but even a 1 psi change seems to dramatically alter the car's handling behavior. Don't vary the psi too significantly at first unless you really want to change how the car behaves.

 

[Nick325xiT 5spd]

I'd imagine those would be pretty nice track pressures. I tried boosting my front once, and it was way inappropriate for regular day-to-day driving.

But then again, my brakes are still good after 14k miles, and I still get 24mpg.

Pathetic! How can you call yourself an enthusiast?

In all seriousness, why didn't you like it for day-to-day driving? What's wrogn with oversteer?

 

[alee]

In all seriousness, why didn't you like it for day-to-day driving? What's wrogn with oversteer?

The honest answer?

I didn't really know what to do with it once I had it. Other than the teenage years where doing donuts in other people's cars was the norm, I really have no practical experience or application for oversteer in everyday driving.

I have a mild understeer tuned in right now, and I feel pretty safe with that.

Ask me again after I get a few driving schools under my belt.

 

[Nick325xiT 5spd]

Generally, it doesn't make much difference to me... But on those really twisty, windy, fun roads, I love the fact that even in my overweight and underpowered 3'er touring responds instantly to a touch of the throttle. :thumb: :thumb: :thumb: :thumb: :thumb: Those are the times when I REALLY love my car, deficiencies and all.

 

[Dr. Phil]

I suggest higher in front. I run between 38 and 44 in front, and 33-36 in back. It cuts WAAAYYYY down on understeer and makes the car a lot more fun.

Doesn't that high of a pressure in the front make for some really harsh reactions when you hit bumps/holes? I'm running 37 all around and have a slight understeer.

 

[alee]

Doesn't that high of a pressure in the front make for some really harsh reactions when you hit bumps/holes? I'm running 37 all around and have a slight understeer.

I'd guess it would be pretty choppy, and bumps would really unsettle the car. Even 37 psi is a little too much for me on bad roads. Everything in the car rattles when I have the psi up any higher than what I have now.

But then again, my car isn't as rigid as a wagon or a sedan.

 

[Nick325xiT 5spd]

I don't find it unsettling at all. My old contis were comfortable (to me) even at their max rated pressure of 50 or so PSI. Try bumping your pressure up a little bit, the worst that'll happen is you'll hate it and drop it back down. As Al said, I DID wear my pads out in 10.8K, so my opinion may opr may not apply to the mainstream.

 

[alee]

As Al said, I DID wear my pads out in 10.8K, so my opinion may opr may not apply to the mainstream.

I would say that is very abnormal.

I would be amazed if 50 psi was actually comfortable. You must have an @ss made of iron. :yikes: To each their own!

 

[Mike 325xi]

After a little experimentation I have mine at 38 all around.

 

[Dr. Phil]

I'd guess it would be pretty choppy, and bumps would really unsettle the car. Even 37 psi is a little too much for me on bad roads. Everything in the car rattles when I have the psi up any higher than what I have now.

But then again, my car isn't as rigid as a wagon or a sedan.

I do take hard hits once in a while with 37 psi, but I like the handling a little better for ramps, etc as compared to when I wa running 34/36 which was recommened by my mechanic friend. It could also be an all-season v. sport tire thing :dunno:

 

[Dr. Phil]

After a little experimentation I have mine at 38 all around.

What about with the M68s?

 

[alee]

After a little experimentation I have mine at 38 all around.

Wow, I guess I am a wussy. Maybe I should go back to my 15 inchers on my Altima. Sigh.

 

[Mike 325xi]

Wow, I guess I am a wussy. Maybe I should go back to my 15 inchers on my Altima. Sigh.

You are a wuss! It's not harsh at 38 at all. Feels very responsive and still rides well.