I upped the PSI to my tires from 29 to 35 and...

[Chris D.]

Originally Posted by trebuchet03

Naw, bring it up to max (and beyond)

Information like that (kidding or not) mite be taken
seriously by a newbie and end up killing them or people around them..

Not a very wise idea...

[SVOboy]

I don't think he's kidding, as many people have said, they're running about the sidewall max rating. I myself run 50/50 in my 44 max tires with no ill wear or handling effects.

However, I do think this thread needs the standard tire disclaimer of "you attempt this at your own risk, and before going out on the highway with higher inflation you should test to make sure that your handling in normal and emergency situations is as good as it used to be. Find a parking lot and stomp the brakes or slam a hard turn to make sure you're not losing critical traction."

[trebuchet03]

Originally Posted by Chris D.

Information like that (kidding or not) might be taken
seriously by a newbie and end up killing them or people around them..

Not a very wise idea...

What SVO said... and, highly unlikely... What's more likely is failure due to under inflation

http://www.officer.com/article/artic...on=19&id=27281
Check out the 100psi Crown vic stock tires

So, for political correctness.... Max Sidewall for liability reasons - beyond by your choice... Go with whatever your comfortable with.

1. Your tires will not balloon out
2. Your tires will not pop/come off the bead
3. Your tires will not explode
4. Your tires will not wear out in the center
5. etc. etc. etc.

[Chris D.]

Originally Posted by trebuchet03

1. Your tires will not balloon out
2. Your tires will not pop/come off the bead
3. Your tires will not explode
4. Your tires will not wear out in the center
5. etc. etc. etc.

Incorrect, how on earth did you come up with that one?

If ANYTHING, I know tires...

[Lazarus]

Originally Posted by Chris D.

Incorrect, how on earth did you come up with that one?

If ANYTHING, I know tires...

Do you have some info or experiences to show other wise. I don't think anyone will tell you run over max sidewall pressures for liability reason just like no ones going to say drive 80 in a 55.

As mention lots of folks are running 50 psi and have gone through set with no ill effects. Auto crosser run higher pressures, stun drivers, and police departments without problems. Personaly I don't think there is that much to be gained between 40- 50 except a rougher ride. But if you have some info please share.

[trebuchet03]

Originally Posted by Chris D.

Incorrect, how on earth did you come up with that one?

If ANYTHING, I know tires...

I didn't come up with that one

It's Engineering my friend This is why you've got a bunch of members with over inflated tires stating they don't have center wear

[Chris D.]

Originally Posted by Lazarus

Do you have some info or experiences to show other wise. I don't think anyone will tell you run over max sidewall pressures for liability reason just like no ones going to say drive 80 in a 55.

As mention lots of folks are running 50 psi and have gone through set with no ill effects. Auto crosser run higher pressures, stun drivers, and police departments without problems. Personaly I don't think there is that much to be gained between 40- 50 except a rougher ride. But if you have some info please share.

I've been an avid Autocrosser for well over 12 years in several different classes..
I worked as a manager of a tire shop for 6 years..

Tires were my thing..

I've ran upwards of 65-70psi while autocrossing on yoko ao32r's because my sidwall indication marks called for it to eliminate roll..

I aligned my own vehicles myself for a variety of different setups which include drag racing, autocross, offroading and recentally commuting.
I've also specialized in countless hours of setting up cars for dynamic alignment (look it up) as well as the standard static alighnment.

If you understand how tires are made (and I do) dd your tires above your specs can cause belt seperation, material fatigue, warping, ect.

one tiny pothole at those #'s will give you a sidewall bubble in a heartbeat, possibly a blow out.. for what little gain you get, its truely not worth it for your safety, others or your ride comfort.. Sometimes FE can be taken too far.. To me over inflated tires are like coasting with the engine off, its just not a good idea and if something happens, your vehicle mite not be able to combat the situation as well as it could because your using the item in ways it was not intended to do..

Sure you can, but just because you can, doesn't mean you should.
I could do 115mph in my truck easily, but I dont.. but have..
I've gotten my autocrosser up on 2 wheels just for fun/show off..

Originally Posted by trebuchet03

I didn't come up with that one

It's Engineering my friend This is why you've got a bunch of members with over inflated tires stating they don't have center wear

theres still much more force on the centers and there will always be more wear than the outters, it mite not be all too noticable or enought for you to worry about replaceing the tires, but they do wear more by doing this..

saying that it doesnt make a difference whatsoever is a bit off..
you mite not physically be able to see it, but with a depth guage you can..

why not get the most out of your tires.. the cost of the tires vs the fe you loose at a safe psi isn't worth it..

crunch the numbers and see.. safety vs. fe..

[johnpr]

i have to agree with bhazard, i have worked in two different tire shops and have seen many issues with tire wear and failure do to wrong inflation, what people dont realize though is that there are more factors than just pressure, vehicle weight, driving style etc. all play very large rolls when it comes to how a tire wears. I am not saying that anyone here is wrong, but i will say that you have to be careful about over inflating tires (beyond vehicle manufacturer specs, tire manufacturer specs are often much higher than this) and be careful when telling people to inflate there tires to max sidewall pressure and beyond. if i still worked for a tire shop i would be more than happy to start documenting this kind of stuff but then again im not there anymore, oh well... next time i work at one (probably this summer) i will start documenting tire inflation related issues. again, im not saying anyone is wrong though because there is more than just tire pressure acting on the tire.

[trebuchet03]

Theres still much more force on the centers

You've yet to say why. Sure, hoop stress increases - but that's not solely on the center.. Unless, somehow, there's a pressure gradient such that only the center of the tire has higher air pressure

There's a mix of bias ply facts being applied to radial tires here.

Yes, you're increasing internal stresses on the belts - I'm well aware of that (that's what we're trying to achieve here). What we're doing is using the FoS built into the tire design.

How did I test my tires? Chalk. Chalk the tires, drive a little, watch for uneven chalk wear. Didn't happen.

If you understand how tires are made (and I do) dd your tires above your specs can cause belt seperation, material fatigue, warping, ect.

I'm halfway through my tire's warranty - and have more than half of my tread left... No abnormal wear. And given the relatively low pressures compared to the high limit for steel fatigue, I highly doubt we've passed the fatigue limit for steel (which is ~50Kips). I'd do the calculation right now for you, but it's late and I've got a few more papers to read before bed

one tiny pothole at those #'s will give you a sidewall bubble in a heartbeat

I hit about 4 pot holes much larger than tiny - at about 30mph earlier today... Woo construction + dirt road (water must have caused some mini sinkholes). Tire's are perfectly fine - it's worth mentioning my car was fully loaded (5 adults + 150 or so pounds of cargo). I'm more worried about cracking my 100% AL oil pan then my tires (for some reason, VW put that as the lowest point o.0).


If it makes you feel better.... Here's what I and many other on this board are trading....

I'll trade higher pressure for my frequent (at least a few times per week) tire checks. This, compared to so many other drivers tooling around with under inflated tires that don't check until their tires look flat. I'm trading higher pressure for better hydroplane characteristics (again, lots of rain for me) in addition to slightly shorter stopping distance - this according to NHTSA.

But, that's all I care to respond to at the moment - well, it's not that I don't care - it's just that I've got some work to do before bed <-- so pardon if my response seems detached and shot gun peppered in it's points

[AndrewJ]

I've been running my tires (rated 35 front / 45 rear) at about 60psi front and 65 rear for several months.

For any n00bs attempting tire overinflation, do so at your own risk. Keep a careful eye on your tires, inspect them regularly, and increase your tire pressures gradually (5psi every couple of days till you hit your mark)

And for anyone worried about overinflation, have you ever rented a U-haul? Every U-haul trailer I've ever rented has had MASSIVELY over-inflated tires. It's no scientific proof or anything, but if it's good enough for rental vehicles that see hundreds of thousands of annual miles of abusive service, it's good enough for me.

Once again, that's just one mans opinion. Oh, and overinflate at your own risk.