Huey52

Inflating to max load capacity would be pointless for me as I am alone in the car most of the time. I don't weigh too much (165 lbs), and my regularly stowed golf clubs are pretty reasonable too as a 'carry bag.'

I'll just stick with the US pillar placard 'normal' load rating inflation psi, as I always have.

ghag_S4racing

My opinon the best thing to do when in doubt is to see how your tires are wearing when you have your tire pressure set.

1> Set the tire pressure to what is recommended
2> In dry weather, drive the way you like (aggressive...whatever)
3> Take a look at the tire edge wear. If the edge tread never touched the ground...your tire pressure is too high. If the sidewall was touching the ground...your tire pressure is too low...

Been following the above suggestion for years and have been very happy. Again this is a suggestion.


Current Ride
2010 A4 S-line 6-Speed (Stock for now)
1981 CJ7 4" lift
Past Fun Rides
2007 STi stage 2
2001 S4 6-speed Stage 3+
2001 S2000 S/C

QUA77R0

Agree for the most part. #3 on your list is not accurate for tire profiles that drop below 40 series sidewall ratios. I have seen 35 series tires that had less than 15 psi and the sidewall was not touching the pavement. IMO, that is basically a flat tire...

You can't go wrong with sticking to the recommended pressure as long as you adjust as needed based on your particular wear symptoms.

It may be interesting to note that the contact patch on the 255/35/19 only achieves even temps at the track by lowering pressure... depending on ambient temps, I am talking about a 8-10 psi reduction or more. That is strictly from my track experience with the B8 though. I raise my pressures before I leave the track.

This is anecdotal, but I noticed that my AMG gas flap lists two sets of pressures. One for sub 130mph and one for speeds in excess of 130 mph. The 130+ pressures are the same as the full load pressures. Since I don't live near an autobahn, guess which pressures I run...

equ

After some experimentation, here's where I've settled on cold pressures for my '10 a4 sport package:
245/40-18 summers: 33psi all around
225/50-17 winters: 34psi all around.