I recently conducted an unplanned experiment with tire inflation. I always inflated my ties to 40 psi and got about 45 MPG. About five months ago I took the car in for routine service at Honda and they took the pressure down to 32 psi without telling me. The gas mileage immediately dropped. It took me a while to notice and a while more to correct the situation. So over about 3000 miles of driving at 32 psi I got about 42 MPG. Now the tires are back to 40 psi and the mileage is again at 45-46 MPG.

 

What's the point? Over inflating tires reduces rolling resistance and grip. You're trading control of the car for 5-10% fuel savings.

 

40 psi may be over-inflated, but it's not bad. I run mine at 38 psi. Some owners inflate to 50 psi.

Most owners think that the recommended 32 psi is under-inflated.

 

Say what? I run at 50psi, and my car handles *FAR* better than it ever did at 32psi. Cleaner cornering at higher speeds, better control in the rain, it's all there.

 

I don't know what to tell you. That's much higher than what any tire guy would recommend. Are you saying it handles better because it feels good to you or because you can perform a cone weave faster? 50psi would be high for autocross and daily driving should certainly be lower than that.

 

I drive a TCH - a heavier car than the HCH. The TCH also recommends 32 psi. I found that pressure too low, and increased it to 42psi (40 psi on the rears). The result was much improved handling, better braking and lower tire wear. After 36,000 miles the factory Bridgestone tires are wearing even, with slightly more wear on the edges than the centers.

The factory recommended pressure is a compromise between handling and ride comfort.

A very informative article on tire pressure is Driving Under Pressure

 

That is interesting. I'll admit, I've never taken a car as heavy as a Crown Vic with the full police equipment work up around a set of cones. I'm pretty sure I've never seen one at a track day, either.

Assuming the author is an expert, and 50 psi is right on target for a vehicle that heavy, the HCH at under 3000lbs should be significantly lower.

 

Keep in mind that our tires are smaller than a Crown Vic's.

Bugger nash for beating me to the punch... I love linking that article when people start getting all uppity about my tires

 

If a complete stranger on the net told you to jump off a cliff...

 

.... I'd go looking for my hang glider.


Or the nearest available dealership lie-nance manager.