tire pressure question?
 

i drive 100% city, and i think raising my tire pressure would help mpg.

i used to pump it up to 44 psi on all 4 tires, 44 sidewall max



but i bought two front new tires and they are LRR, but the front 2 tires only have a max pressure rating of 35. while on the back, one of my tires popped so i had an extra tire at home. the other tire still has alot of tread so i didnt change it


the rears, are mismatched. one side the max pressure is 44, the other is 36


so, i just pumped the fronts to 36,

the rears to 38






any suggestions on what should i do or how high can i go on the pressure?

I have a similar situation. I think, first, probably not a good idea to have mismatched rear tires. I'm pretty sure I've heard that that is not a good practice. My tires are also 35 front and 44 rear. But my rears are at least not mismatched. I have my fronts and rears at the same pressure of about 51. Although I think the increased pressure may be aversely affecting my handling in wet conditions. I actually started sliding going around a turn in neutral in the wet. I always tear around the turn in neutral to maintain momentum since it's a tight S turn underpass. I feel that the increased pressure has improved handling in dry conditions but maybe worsened it in wet conditions. Granted if I had been in gear I probably wouldn't have slipped, but still, I wasn't even taking it fast, and I'm never in gear in the dry. Maybe some other people have some experience with over inflated tires in the wet.

As far as blowout concerns, I heard the Car Talk guys say you can go up to 200PSI before the tires will blow out from over inflation. There is an article somewhere on this site of a car riding on two wheels with tires at 100PSI. But I guess the issue is how "over-inflation" (some people would argue regular max sidewall is too low for optimum tread wear and overall traction) effects handling and traction, and what is the optimum pressure. I imagine it would vary from car to car and tire to tire. It's sort of something most people experiment with: incrementally increasing the tire pressure and then seeing how it goes. One thing someone suggested to me was that you should avoid having the rears inflated more than the fronts, especially if your car is particularly front end heavy (most cars are), as higher pressure in rear with less weight back there would make the car more prone to sliding out.

Side to Side - you should have similar tire pressures. Keep in mind that the max pressure rating is the pressure required to support the rated max load.

so,

with my fronts beight LRR tires and a max sidewall of 35, how high can i go and still be safe, and it wont cause fast wear of tire? i want to be safe than sorry, dont want to sacifice safety to get 2 mpg or something like that