DD694

I noticed yesterday that the manual calls for air pressures of 33 PSI front and 39 PSI rear for 19" tires. The sticker on the driver's side door jamb on my 997S calls for 34 PSI front and 40 PSI rear. These are both for 2 people in the car and no luggage. I wonder what changed.

MJones

You are correct!
What to believe?

The product info guide lists the tire pressures more precisely as
33.36 F
39.16 R
@68°

rnlarctic997

I'm following the guidelines on the doorjamb--I think the handling is sharper during turn-in with negligible effect on ride quality.

PDQ PDK CAYMAN S

I have 4500 miles and 33 & 39 lbs and the tire wear looks even.

Viken

Those are conversions from the metric *bar* measuring units. The factory specified numbers are:

Front: 2.3 bars x 14.503775 = 33.35868 psi
Rear: 2.7 bars x 14.503774 = 39.160187

So, whether you follow the manual or the door jamb sticker, you shouldn't feel any difference.

gradyex

I keep my pressures around 35-36 psi in the front and 43-44psi in the rear. I do carry passenger(s) often. Mine are 19" rims, classic style, 997S. Check your tire pressure often at least every 2 weeks (weekly is better). A good air compressor in the garage is not a bad investment and can be used for many other things besides adding air to a low tire (the one that comes with the car is ok to add a couple of pounds occasionally, but I wouldn't use the thing on a regular basis as its really designed for emergency use. Be sure to bring a book if your tire is completely flat).