Tire Pressure

[doug73cs]

Given the improvement in tire construction, compounds and profiles I wonder if the recommended tire pressure that came from BMW is still the optimum. Guess trial and error to see what works best is one approach but I'm curious what opinions are out there in bimmerland.

I run 13" Yoko Avids at 30psi. A mechanic who did the initial import inspection recommended 34psi as a starting point.

Not a real fan of all seasons but can't risk true summer tires in the land of ice and snow.

Doug

[TobyB]

Funny.

The sticker recommends lower (24? 26?)

and we run competition tires and lapping day tires

in the high 20's- hot!

It does depend to a significant degree on the size of tire...

I run the street car at 25 cold, just because it seems to work there.

t

[Mike Self]

front.

I've noticed that I get more tread wear in the tires' center than the edges, and that's indicative of slightly high pressures. I would think that with 34 psi you'd get even more center wear.

Of course I bump the 30/28 up for autocrosses.

mike

[TobyB]

Hmmm, and if I split pressures, I usually run 2-4 more in the front

which helps loosen the rear of the car somewhat.

And the front weighs more, so there's that...

t

[Napes]

With 19mm bars front and rear the car tends toward understeer so I run

32# front and 30# rear, set first thing in the morning before any sun is on the tires.

Bob Napier

[Mike Self]

some understeer (urethane bushings up front, rubber in the rear). Perhaps I should try more air in front and less in the rear for a little more tail action...

Factory always recommends more air in the rear tires than in front, whether loaded or unloaded...

mike

[KFunk]

I always like a good bit more air pressure in the front than the rear. I aim for around 34psi in the front and 28 psi in the rear... with the r-tires or Azenis at autocrosses.

Less pressure in the rear has always helped get rid of oversteer for me. If I go too high of a pressure in the rear, I get way too much wheelspin and oversteer. I like the front to be higher for rock solid bite into the corner and quick transitions.

Of course, its always up to driving style, as what works for me has sometimes been completely different for a co-driver.

And yeah, I've got big ole sways. I'm currently running without a rear sway bar though, in order to keep wheelspin down.

I don't even pay much attention to tire pressures when street driving... theres no point in cornering hard on a public road, its too easy. I just run 30 or so psi all around...