Maximum tire pressure

[DracoFelis]

Originally Posted by holypaulie

What maximum pressure I can pump in my tires if maximum tires pressure is only 35 PSI ?

IMHO any pressure (from your car rated pressure) up to your tire sidewall pressure (in your case 35psi) should be totally "safe" (except for any issues relating to the harsher ride from higher psi). In fact, higher pressure (as long as it's not too high) should actually lower the risk of tire damage/blowouts (due to the higher pressure helping the tires to keep their shape).

Of course, since most tires have a considerable "safety margin" built into their maximum pressure ratings, you are probably OK going considerably above the sidewall pressure, as long as you don't get too carried away (for example, 50psi could easily work OK in your case). However, whenever you go beyond the max rated tire psi, you are "on your own" as it were.

BTW:
I personally have 44psi rated tires on my CRX, and I have run them most of their life at (so far around 19,000 miles) at around 42psi (2psi under the sidewall max rating). And so far I've had good results with that setup, with no indication (at least no visible indication) that I've got any premature wear.

However, when I recently had them balanced and rotated, the guy at the tire store was really surprised that I wanted 42psi, and asked me if I was really SURE I wanted that high of pressure. He then told me that was very high pressure for such a small car, and that I am risking "blowing out my centers". However, he did go ahead with my wishes, after I confirmed that I really was sure I wanted that high of pressure.

Of course, despite the warning from the tire guy, I'm really not going to worry about what I'm doing. After all, if there was going to be significant (abnormal) wear in the tire centers, I think it would have become obvious by now (since I've already run the tires over 1/4 of their rated lifetime at that higher pressure). So (since the tire wear still looks fine) IMHO at worst the tire tread (center) may die a few thousand miles before it otherwise would (and I can live with that, if it happens). But OTOH I've also heard that higher tire pressure can sometimes help the tires wear more evenly. So it could also go the other way, and I may get extra life from my tires, due to the higher pressure. And in either case, I think the higher tire pressure helps my FE, and it clearly helps my rolling distance when I'm coasting...

[baddog671]

Ive seen cars with 35psi tires come into our shop and they peg the tire inflators, which go up to 120psi . Crazzzy peoples...

[cfg83]

holypaulie -

I just found this :

CLICK & CLACK : Inflation Effect - Sunday, September 30, 2007; Page G02
http://www.washingtonpost.com/wp-dyn...092900659.html

Q Dear Tom and Ray:

I was driving from Flagstaff, Ariz., to Tucson, and the tread blew off the front driver's side tire. The tire guy tested the pressure and said someone must have put air in the tire. But it had been several months since any service. Can altitude, barometric pressure, heat or speed affect the tire? -- Bryan

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A TOM: You're a lucky guy, Bryan. Often, when one of the belts blows off, the whole tire comes apart. Including the air. And at highway speed, that can be extremely exciting!

RAY: Overinflation probably had nothing to do with this. It had more to do with the age and condition of your tires.

TOM: To get more details, we checked with the Quincy, M.E. of the tire world, Bill Woehrle.

RAY: Bill spent his career as a tire engineer and now runs a company called TFI: Tire Forensics Investigation.

TOM: Bill says overinflation almost never causes tire failure. The standard tire is inflated to about 30 to 35 pounds per square inch. In hot weather and highway conditions, the temperature inside the tire rises about 50 degrees. That increases the pressure about 5 psi. The burst pressure is about 200 psi. So unless you had your tires pumped up to 195 psi, you didn't come anywhere near bursting the tire from too much pressure.

RAY: Bill says the most vulnerable part of any steel-belted radial tire is where the belts are attached to the rubber near the edges of the tread. If the tire isn't abused, those belts should stay attached for the entire tread life.
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TOM: But if the tire is defective, is at the end of its useful life or has been abused in some way, the top belt can separate. When it tears, it tears violently, so it's a crapshoot as to whether the next layer of rubber will tear too and cause a blowout.

RAY: And the most common form of abuse is under-inflating your tires.

TOM: Let's go back to our forensic tireologist. Woehrle says underinflation puts additional stress on the tire's shoulders, where the belts are attached. And if a tire is underinflated by 10 or 15 psi, the temperature at those shoulders can reach 200 degrees. So you've got a vulnerable part of the rubber that's hot being stretched and pulled, and that's a recipe for tire failure.

RAY: So for all of our readers: Make sure your tires have sufficient tread and have not exceeded the manufacturer's mileage rating. Make sure they're less than 10 years old (because old rubber gets brittle and has a greater tendency to crack). And check your tire pressure at least once a month to make sure your tires aren't underinflated.

CarloSW2

[GasSavers_Ryland]

I kind of feel like there should be a disclamer on pages like this, the max presure listed on your tires states 35psi, if you go past that you are then going past the stated design presure of that product, when you go beyond the design limits like that you put your self and your vehicle at risk and you should be aware of that insted of simply going at it blindly, learn how to moniter your tires for stress, wear and damage, and if you notice that it's creating a problem then lower the presure!
I have tires that are rated at 44psi ran 50psi for about 15,000 miles and have run over debree with one of the tires 3 times, leading me to use tires plugs in the holes without much issue other then possibly putting the tires out of ballence.