Seems most you guys are running about 55psi, has this been determined to be a rough magic number, or did you all just add a couple psi till you happened to get there?
Just asking, because I do a lot of biking, and its been shown that higher psi doesn't always mean better rolling. Especially on rougher terrain where you end up bouncing off things rather than rolling over them. I'm just wondering where the point is on a car?
The mfg. spec allows for a certain amount of ambient temp change, plus heating up from rolling at speed.
So I don't go tooo far beyond max sidewall when the outside temps are very changeable. I don't know what amount of outdoor temp increase the mfg. assumes they have to allow for - but my guess is that's what we're using when we inflate beyond max sidewall. So if mornings are 40 and I can expect 90 in the p.m. then I won't inflate (in the morning) much beyond max sidewall. By afternoon, before I start my drive home they'll be 5 psi more just from outside temp. If I only expect a change of about 30 deg. then I might go higher than max sidewall.
Right now I'm kinda waiting for the season to stabilize a bit. We've had up and down temps lately but I think it's time to put my 35 psi tires up to about 38-40, measured cold in the morning.
Currently getting +/- 50 mpg in fall weather. EPA is 31/39 so not too shabby. WAI, fuel cutoff switch, full belly pan, smooth wheel covers.
on my civic vx I have 165/70-13" firestone f570 with a 44psi max presure rating, I've had them for just about 2 years now, have put almost 30,000 miles on them, I have them set at 50psi and when I've taken them off to rotate, or change in to snow tires I've checked the tred for wear, and it's extreamly even.