Posted by Ted Getchell on September 25, 1998 at 10:53:33:
In Reply to: Re: Tire Pressure Question posted by EM on September 25, 1998 at 09:29:59:
Good advice and you are right. Blowing a tire at speed in a fast sweeper would be very ugly. I AM talking cold pressures in my question and understand how the pressure builds. I wish I could find a way to talk to some tech person at Michelin, but there doesn't seem to be any access at their website. Any ideas?
: I'd be VERY careful about exceeding a manufacturer's maximum recommended pressure -- especially at the speeds you mentioned!! You certainly don't want a catastrophic failure or you might damage your car (or yourself). Also, you don't say whether the pressures you're running are taken hot or cold. Remember, if you use air (not nitrogen), the pressures will increase as the tires heat up.
: Keep in mind that sidewall rollover is not only a function of tire pressure. It results from the interaction of your other suspension components with each other. What about your tire speed rating, shocks/struts, camber settings, sway bar size, tire temps, etc.? Granted, if you need to do something here, it isn't as easy as changing tire pressures (or as inexpensive), but you have to consider the whole package to remain safe.
: : Hi 5ers!
: : BMW recommends 33psi front and 41psi rear on my 95 540iA. I currently am running Michelin Pilot XGT V4s with a maximum allowable pressure of 44psi (225/60 R16).
: : When on the track I would like to take the front tire pressure up 5 - 6 psi based on observed scuffing a little farther onto the tire shoulder than you would want. Because of the 44psi max, I can't go up that much and maintain the 7 psi front to rear pressure differential.
: : My question to the group: How important is the 7 psi front to rear difference? I realize I could do lots of testing to figure this out, but I am hoping that someone out there is willing to share their experience.
: : Thanks.
: : Ted
: : '95 540iA