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MNBoxster · 09-10-2006, 03:19 PM

Hi,

As mentioned go with the Manufacturer's recommendation, but play around 1-3 PSI depending on your tatste, driving style and road conditions.

The sidewall values are the MAX values which you should run the tire, but not for every application. The Tires are not model specific, but are sold for any number of models and makes (consequently weights and loads).

The Porsche recommended pressures are not absolute. Porsche determines this PSI using many criteria including maximum load (if you never have a passenger, a little lower pressure won't hurt), ride comfort, ease in parallel parking, etc. The value is the best compromise they could come up with. If you live in an area with poor roads (cracks, potholes, etc.) you may want a few more PSI to avoid damaging a rim should you hit a pothole. Likewise if you enjoy a little firmer ride or live in a Wet climate (the harder tire will channel water better, but only 1-2PSI!!), also if you're a long distance interstate driver because you'll maximize MPG.

Varying 1-3 PSI won't blow up the car or put the Tires through undue wear and tear. Learn to read your tires too and if overinflated, wear will be more prominent in the center of the tread, more so on the outside if underuinflated.

In general, underinflated is worse than overinflated (within 1-5PSI). Remember the Ford Explorer? All affected cars were on underinflated tires. This was more responsible for the trouble than the make/manufacturer of the Tire, but this was no good because it left no one for the lawyers to sue, so they went after Firestone...

Happy Motoring!... Jim'99

09-10-2006, 03:19 PM	#10
MNBoxster Registered User Join Date: Sep 2005 Location: Minneapolis/St. Paul, Minnesota, USA Posts: 3,308	Hi, As mentioned go with the Manufacturer's recommendation, but play around 1-3 PSI depending on your tatste, driving style and road conditions. The sidewall values are the MAX values which you should run the tire, but not for every application. The Tires are not model specific, but are sold for any number of models and makes (consequently weights and loads). The Porsche recommended pressures are not absolute. Porsche determines this PSI using many criteria including maximum load (if you never have a passenger, a little lower pressure won't hurt), ride comfort, ease in parallel parking, etc. The value is the best compromise they could come up with. If you live in an area with poor roads (cracks, potholes, etc.) you may want a few more PSI to avoid damaging a rim should you hit a pothole. Likewise if you enjoy a little firmer ride or live in a Wet climate (the harder tire will channel water better, but only 1-2PSI!!), also if you're a long distance interstate driver because you'll maximize MPG. Varying 1-3 PSI won't blow up the car or put the Tires through undue wear and tear. Learn to read your tires too and if overinflated, wear will be more prominent in the center of the tread, more so on the outside if underuinflated. In general, underinflated is worse than overinflated (within 1-5PSI). Remember the Ford Explorer? All affected cars were on underinflated tires. This was more responsible for the trouble than the make/manufacturer of the Tire, but this was no good because it left no one for the lawyers to sue, so they went after Firestone... Happy Motoring!... Jim'99 Last edited by MNBoxster; 09-10-2006 at 03:23 PM.