Tire Question

[hanzo040107]

I have a MS3, I see the manufacturer's recommendated tire pressure but it seems low to me considering the tires can go 44 PSI max. Is it best to inflate them to near max? Would the car's handling, braking, etc suffer because of it? Anyone have a clue why the pressure is set so low? Does it trip the TPMS sensors to set them to about 44 PSI? It did on my friend's Scion that's why. Any input would be great, thanks.

 

[Sacrilicious]

the tire pressure is set to 30-32 PSI because it's a "cold pressure"...as you drive around, you heat up the tires and air inside, which increases the tire pressure. during the summer, you can gain 5-10 degrees from driving around, so that's why they leave so much clearance to max pressure rating.

if you went crazy on tire inflation, you would get better gas mileage and more responsive handling, but the tire would likely blow up when you went over a bump...^^;

 

[Mid_Life_Crisis]

I have a MS3, I see the manufacturer's recommendated tire pressure but it seems low to me considering the tires can go 44 PSI max. Is it best to inflate them to near max? Would the car's handling, braking, etc suffer because of it? Anyone have a clue why the pressure is set so low? Does it trip the TPMS sensors to set them to about 44 PSI? It did on my friend's Scion that's why. Any input would be great, thanks.

I don't think 32 is all that low. Once the tires heat up it should get to 35 or so. Running your tires too high or too low is going to effect your contact patch with the road. Too low and they ride on the edges too much and lose stiffness. Too high and they ride on the center section and lose contact area. The pressure depends on how much stuff you tote around, how many people are usually in the car, in other words, how much weight is in it. Except for unusual situations (like going to the track), the best tire pressure is the one that gives you even wear across the tire. This means you are getting the biggest possible contact patch, which means the best possible cornering. Not to mention they'll last the longest this way. For me that means a cold pressure of about 35 lbs. For you it might be different.

 

[Rotus8]

The maximum tire pressure on the side wall is just that, the maximum. The optimum pressure depends on may factors, which the manufacturer has spent a lot of time figuring out. You can optomize it, but start near the factory number. On my roadster I run 14 in the front and 15 in the back (no, that is not a typo). Some in my group run as low as 12, but weigh in the 1200-1300 pounds range.

 

[bykeryder4life]

yeah go fill your tires up to max and try to launch, the harder tires will break free easier and just spin. when you drop the pressure down the tire absorbs more surface area on the street to put the power down to the ground. just like going in sand with a truck you air down for traction

 

[hanzo040107]

Cool. All good advice. I think I learned something new about "cold pressure." Surprising my 240 tires haven't given up yet. I usually end up changing my stocks out with wider tires & usually fill up to max, guess thats not the best idea now. I knew that part about changing the air pressure & changing the contact patch & grip though. But still all good info, guess I just gotta figure out my ideal pressure for my area.

 

[Sacrilicious]

what is your area, btw?

 

[SwampAss]

I run higher pressures in my car tires (about 36/34 to 38/36) I prefer to keep the heat out of them for longevity.

 

[hanzo040107]

H-A-W-A-Ah_Ah.