You would be amazed how many people say this. :facepalm:I've always heard that it's best, for fuel economy, to use the maximum tire pressure listed on the tire.
You have to realize that low profile tires are going to look flat when they are not. If you run stock tire size you need to go by what the manufacturer of the vehicle says. The "max tire pressure" on the side of the tire is just a rating to match the tire to the vehicles requirements. "Max tire pressure" means that is all the pressure that the manufacturer of the tire rates it can hold safely.You drop the tire pressure for the twisties? I think 32psi and less (30?!) is near being flat.
For normal driving, I run 43f/38r... and I can tell if a tire is less than 35psi as it'll start plowing when it shouldn't be. At 43/38 my tires wear evenly for the tires I have, my suspension, and driving style. For autocrossing, I run 51f/43r.
When I was running stockish sized tires, I ran 37f/35r.
I only agree with that if your running wrinkle slicks. That doesn't apply to conventional tires or drag radials.If your racing your car it is always better to lower your tire pressure because you get better traction. Too much pressure doesn't allow the tire to flex and is realy stiff. Therefor it slides instead of flexing and gripping.
I tend to run mine in the mid 30's (~2.5 bar) on the street. The ideal pressure will vary depending on tire size and model, but on my 225/45/17 Kumho Ecsta MXs, that seems to be about right for regular driving.I am running 2 bars (28 psi) on my 205/40/17`s. Is that too low? Tire wear seems even.