Well I don't know if it's psychological, I did try this when it was raining to the point there was flooding in our area. I know how the car behaved at lower psi and I would get the odd hydroplane effect here and there. And stopping would always get the anti-lock kicking in. With the increase I noticed none of that, but the number one reason why I think it really does work is because my wife who is the primary driver of the car had no idea she was my "guinea pig". And she would make comments like, I had no problems in the rain today. And I would just smile. ha-ha.

As for my test it was done over 2 months (1 at MAX and 1 at +5 psi)... 8 trips to the station. And the weather for both month was essentially same with a monsoon on 2 days of the MAX psi test.

Driving distance in both month was the same, and same routes were taken. Mileage did NOT improve to the point that I can credit a single MILE per gallon. I can credit up to 10 or so miles over an ENTIRE tank.

It's a simple test that most people can do themselves, they just have to be honest about the test and drive the same.

That thought did cross my mind! I find myself driving accordingly to keep up a good tank average if it starts off well in the first 100 miles!

But I did fill up my tires to 35psi last time I was at the gas station. They were at 28, which is even below the 30 recommended on the door sticker (maybe the techs didn't check the tires last oil change!!) Maybe it helps to have them back up to (or above) the minimum recommended. Maybe I'm driving differently this week, but I am getting 46.1 mpg this tank, over my usual 44 average.

However, I am not going to make any calls on whether it was because of the tires, the weather, or chance until a few tanks down the line. I try to drive the same way all the time, and I definately drive the same route all the time, but I know the milage can vary from tank to tank.... so, we'll see. If after about 3 tanks I'm still up at 46, I'll probably keep the tires at 35psi or so. I'll keep you all posted!

Thanks for the input, everyone
--A

Add to this thread that higher PSI = longer tread life.
The reason is simple less flex = less stress = less wear.
Excel claims that the effect most noticeable when you get near 50 PSI.

People who run very high pressures generally report that uneven
treadwear is a myth. At least the effect is not pronounced enough
to undo the increased overall tread life.

For that reason I run at 48 (sidewall is 44 so I am not pushing it too much).

And I like the stiffer ride, I would prefer tighter suspension and less power
assist in the steering too, but that is another thread.

I might get to try some light snow driving in two weeks in a trip to tahoe,
I hear that I should drop my PSI for that, can anyone elaborate and
maybe give a few hints as to optimum PSI for that (I have the bridgestones)?

- Kurt

There is precious little discussion on this thread of the change wrought by higher tire pressures on ride and handling. I like a smooth softish ride. I guess that Honda engineers have to find a happy medium between the needs of FE and the comfort of its buyers. What do people think?

Go as high as your back and butt will allow. Nuf said.


Ron in SoCal

Saving the Dinosaurs . . .

The short answer is that ride gets worse, and handling gets better in
all conditions except snow when you increase PSI.

Nobody mentioned the FE boost in hard numbers yet. It tends to
come in just over 1 mpg/10PSI, so not noticeable unless you do a very
controlled test (which people in this forum have done in the past).

Mostly higher PSI tends to transmit road vibration through a bit more.
It is the little bumps, like tar stripes and pavement cracks that tend to
come through a bit more. Those slightly rough freeways are where you
notice it most.

Overall the change isn't that dramatic, I am not sure you would
even notice it unless you were looking for it. Although a pregnant
woman would probably disagree. :-)

- Kurt

Kurt

Thank you for that reasoned reply. I will experiment week by week adding 2lbs at a time and see when and if I and my family notice the difference?

Nigel

I wouldn't recommend going over the max psi located on the sidewall of the tire...I have seen one too many over-inflated tires explode. (I worked for Discount Tire Co., back in the day.)

Tempus fugit, memento mori...

I run 48/46 F/R psi of Nitrogen. I've not noticed any ride, cornering, or stopping issues. Actually I'm impressed, the car performs very well. Of course my other car is a C5 Corvette, so I'm used to the somewhat harder ride. The car feels very stable with the higher psi's. No worries.

'07 HCH w/Nav, '04 Corvette Z16, '98 Corvette Pace Car, '04 Chevy Avalanche.
HCHII Mods: Tinted windows, PIAA 4150K Headlights, PIAA 004X Fog Lights,T/P F/R 48/46 nitrogen.

Sorry. I'm going to call shenanigans. How can you see an over inflated tire explode? It couldn't be customer tires unless they coincidentaly exploded at the shop. Was it on the machine when you were filling it up? How much PSI until it exploded. Or if a customer brought it in, how do you know it was over inflated when it was exploded?

I find your statement hard to believe after actualy talking to one of the engineers. It is stated as fact 100PSI is the minimum PSI noted for a tire to explode. Even if you put in 60PSI and it went up because of the temperature outside and lots of highway driving/cornering I don't see it gaining 40PSI from heat.

Also, were these steel belted tires or tube tires?

Sorry for a bit of a rant. But I'm not buying your story.

My hydroponics experiment

You ever notice how hard it is to lip read cartoon characters?
"Crazy is what the sane call Delta Flyer"