Tire pressures for OEM 20s

[Frenetic]

Just curious what tire pressures people are running?

The door sills shows 44 PSI. I had to take a double take on that pressure. Do people run it that high?

I just checked my cold tire pressures and they are about 35 PSI all around from the dealer.

What pressure do you set it at for normal driving?

[corb2000]

I run my 20s at 38 psi just to give a bit more flexibility in the tyre sidewalls and improve the ride comfort


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[Velopod]

Yup - low profile tires + heavy car = high pressure!

I run 41-42 psi on my 275/35-20s that have a bit more volume then the stock 255ers.

My Porsche only calls for 31 psi on the front - the car is over 1,700 lbs lighter!

[SleekS7]

My dealer set my 265/35/20 tires to 41psi one visit and 44psi another visit.

[ryanlada]

I run the recommended pressure and it seems to handle better (less wander). The ride is a bit harder though.

[tenspeed]

38 front and 36 rear for two people.

The pressures on the door jamb are for five people and luggage.

PSI 02.jpg

[MP4.2+6.0]

38 front and 36 rear for two people.

The pressures on the door jamb are for five people and luggage.

PSI 02.jpg

+1. Always go w/ the greater detail in the manual. Following the Ford Explorer/Firestone 500 fiasco the pressure stickers were dumbed down and standardized. Now only the max load pressure is permitted to be listed for USA spec cars, also now mandated down to the type face, color scheme and location on the B pillar. Euro stickers would have more detail/useful info, as did Audis until circa 2007. As a practical matter, from over 100K miles experience w/ 275/35-20's on my 2006 D3 A8 W12 (as in, both heavy and lots of power/torque), 44psi would result in premature center wear if run for life of tire; more so in the back.

[Frenetic]

Thanks. Haven't read that page yet. I've always followed the door, but didn't realize it was so conservative in this car. The LS 460 I had didn't list different values, showing the same in the door and book and just one value, 33 PSI.

[Clipse3GT]

41 front and 42 rear. No issues with tire rolling on cornering. Plus a bit of extra pressure in rear helps with rotation a bit more on turns. Too much pressure on the fronts will get you more understeer. I found at 44 you wear the center of the tire faster.

[-Eric-]

They do require quite a bit of pressure. It's the MOSTLY the volume of air that supports the car not the structure of the tire. For high performance driving 44 PSI is not unbelievable. The manual does suggest lower pressures and I run them at 44 PSI up front. At the back I am running a bit higher (44 PSI) to adjust the handling balance. If you really want to know if you're at the right pressure you can buy a pyro-meter to measure the temperature across the tread. (from outside to inside) If you're using the whole tire evenly the temps should be pretty consistent. If not you may need an alignment adjustment or tire pressure adjustment. But if you don't want to do all that, you can always run a chalk line from the wheel up and over the shoulder of the tire and onto the tread. Go out and drive the car as normal. If you're rolling the sidewall of the tire over too far you'll see the chalk scrubbed off the sidewall as well as the shoulder. Be carful about dropping too much pressure for "comfort" as you might end up with a bent wheel. The barrels of our wheels don't like it.

[VVG]

Yup - low profile tires + heavy car = high pressure!

I run 41-42 psi on my 275/35-20s that have a bit more volume then the stock 255ers.

My Porsche only calls for 31 psi on the front - the car is over 1,700 lbs lighter!

To add....if you run a lower pressure on a car this heavy with high performance tires, you will burn through them at an alarming rate. As it is, most max performance tires will only be good for like 15000 miles. I run at 44psi front/42 rear

[Frenetic]

Hmm, seems like people are kind of split over this.

I just tried 42 all around and it was a bit too stiff for me in dynamic.

I dialed it back to 38 and it was much better.

I think I'm going to leave it there for now and just monitor tire wear. I don't track my car, run triple digits speeds or carry a bunch of passengers for the most part, so hopefully it works out fine.

[rbpeirce]

I have an A7 and use the pressures recommended in the book. It is just about perfect for street driving. However, I'm hoping to get an S7 or RS7 and I've been playing around with an S7 in Assetto Corsa. I've found 40/37 hot works great in the sim. Based on track experience with my Porsche, up to 43/40 might prove better on track.

I did find, given this is a front engine, AWD car, that the left front tire really overheated at Watkins Glen. I put it at 43 and it helped a lot but didn't really cure it. The take-away is use caution on tracks with a lot of high speed turns. 40/37 works fine at COTA, Laguna, Mid-OH, Pitt Race and VIR.

[MVR 155]

I run 40 psi in the stock P-Zeros on my S6, going up to recommended 46f/48r is plain harsh!!!