Recommended Tire Pressure
#16
Burning Brakes
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Compelling argument; 31/34 it is. Thanks again. Still there is just something about the term "comfort pressure" that makes my anus switch in a bad way. :0) With regard to the speeds I actually drive at, where, and how I'm not in jail for it, well, I'm just not "smart" enough to say much, but I certainly do miss living in Stuttgart-Botnang. :0)
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Compelling argument; 31/34 it is. Thanks again. Still there is just something about the term "comfort pressure" that makes my anus switch in a bad way. :0) With regard to the speeds I actually drive at, where, and how I'm not in jail for it, well, I'm just not "smart" enough to say much, but I certainly do miss living in Stuttgart-Botnang. :0)
So far as I know, they've said nothing publicly, but obviously Stuttgart finally agreed that the only people who need those high pressures with big differentials front to rear are the ones who live with an unlimited Autobahn nearby and they use it at times when traffic is light enough to permit sustained high speeds.
I lived in Europe in the sixties and let's face it: 165 mph is damned fast anywhere. But "comfort pressure" sounds like the guys at Stuttgart were miffed at Porsche Cars North America for insisting we wanted a pressure spec that didn't make the handling iffy at trivial speeds like a hundred mph, and we might even appreciate the extra tire life that correct pressures provide. "Oh, alright. If Americans are such vimpy fellows, ve will provide a spec for your little tushies."
Gary
#18
Burning Brakes
After changing wheels to the winter set, the dash display asked "Did you change wheels? please reset TPM". hehe. I went and set TPM to 20" winter tires and it auto-calibrated everything. Awesome!!
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Will be interested to hear about your tire pressure experience at the track. I find that, even just with spirited street driving, pressures (all around but particularly in the rear) rise faster and higher than with my now departed Boxter S and 911s. I suspect the new suspension/architecture is more capable so tire loadings are higher. Or, if F1 this year is any indication it could be the P Zeros!
Gary
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You do know you will need a decent pressure gauge eventually don't you, Nico? Swapping wheels every time the pressures get off isn't cost effective in the long run...
Gary
#21
Burning Brakes
Enjoy your track time coming up! Love reading about that. I haven't tracked a car before but am a member of the PCA and hoping to attend some events as the weather clears up next year. I could use some driver's training at least.
#22
Nordschleife Master
Compelling argument; 31/34 it is. Thanks again. Still there is just something about the term "comfort pressure" that makes my anus switch in a bad way. :0) With regard to the speeds I actually drive at, where, and how I'm not in jail for it, well, I'm just not "smart" enough to say much, but I certainly do miss living in Stuttgart-Botnang. :0)
Look at the label I posted on post #8 - no reference to comfort or performance. Just a 4 cell table relating to weight and speed. Pick the cell where you fall. Simple!
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Comfort tire pressure for summer tires up to 165 mph (270 kph)
and the following text reads:
The comfort tire pressure speed threshold permitted for your vehicle depends on the national type standardization and is displayed under "Comfort pressure" in the "Tire pressure" menu on the multi-function display. [emphasis in original]
See what I mean about consulting engineers having more work in the future?
Gary
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Anyone nearby should come out to the Fairplex (in Pomona Ca) this Sunday (Nov 18). We have waived late registration fees for this last event of the season. Novice ground school is 5-7:00 Saturday afternoon at the Jockey Club inside Fairplex. (Use Gate 1.)
I just copied your quote and my note to a new thread, Nico. Just realized this is the last chance this season for L.A. drivers.
Gary
#25
Nordschleife Master
Yes. That is the term used in 991 documents, Tony. For example, page 265 of my owners manual is headed:
Comfort tire pressure for summer tires up to 165 mph (270 kph)
and the following text reads:
Instructions about setting the load condition precede a matrix of values for 19" vs. 20" wheels and part vs. full load and Carrera vs. Carrera S. And of course each entry in the matrix is provided in psi, bar, and kPa. Sigh.
See what I mean about consulting engineers having more work in the future?
Gary
Comfort tire pressure for summer tires up to 165 mph (270 kph)
and the following text reads:
Instructions about setting the load condition precede a matrix of values for 19" vs. 20" wheels and part vs. full load and Carrera vs. Carrera S. And of course each entry in the matrix is provided in psi, bar, and kPa. Sigh.
See what I mean about consulting engineers having more work in the future?
Gary
It may be then that 31/34 is a softer limo setting. Then I would say 32/36 (or 33/37) should work fine for sport driving. After all the 991 and the 997 weigh about the same and patch sizes are similar. I use those pressures on my 997.2 S and in my driving style they quickly rise to 37/42 with solid grip on M-PSS.
Re. PSI, bar, kPA conversions, some of us do the conversion in our heads.
Is there a PDF version of the 991 Owners Manual available? PAG has an online doc site but that does not replace a comprehensive self-standing documents.
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Thanks Gary! It definitely looks that PAG is pandering to the soft boulevard crowd.
It may be then that 31/34 is a softer limo setting. Then I would say 32/36 (or 33/37) should work fine for sport driving. After all the 991 and the 997 weigh about the same and patch sizes are similar. I use those pressures on my 997.2 S and in my driving style they quickly rise to 37/42 with solid grip on M-PSS.
It may be then that 31/34 is a softer limo setting. Then I would say 32/36 (or 33/37) should work fine for sport driving. After all the 991 and the 997 weigh about the same and patch sizes are similar. I use those pressures on my 997.2 S and in my driving style they quickly rise to 37/42 with solid grip on M-PSS.
Then we suggested 997 drivers would find that irritating as hell because the TPMS would be in a constant alarm state. As you know, it was designed to look for 34/40, the light-load Autobahn pressure. Christian muttered something about disconnecting the TPMS; I settled for running my tires at 34/37 except on track days. So that was the final number I suggested to 997 drivers who asked, and it's what I say when students with a 997 ask my advice on pressures. Novices don't need the distraction of big red exclamation marks flashing while they're on track. But the real conclusion for 'sport' driving was 30/32. It's just that a 997 thinks the tires are going flat when you run them at those pressures.
I expect to be very happy with 31/34 at the track Sunday, but you know I'll provide an objective report when I'm done. For my style of driving, it might work better with only a two psi differential, but a DE day is not a race. Three psi apart will be fine.
Gary
#27
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#28
Three Wheelin'
Hi Gary - I have always enjoyed reading your posts given your knowledge. Had a quick question re; adjusting for tire pressure using the TPM, as the manual is confusing on the issue. I have a Panamera GTS, but the basic system is the same as the 991, so I happened across this thread.
Anyway, prior to getting this car, I was always under the impression that tire pressure should be checked in the morning, when tires are cold, and I used a very good gauge. Anyway, if now relying on TPM given the indicated setting (standard, partial load), should I assume that the TPM should be looked at in the morning as well, and the "fill" function used when the tires are cold? Obviously, as one begins to drive, the TPM is going to indicate (+2 or so), as the tires heat up, which was kind of a neat ongoing monitoring.
So, I was somewhat confused if the general goal was to have "0's" all around when the tires are at a normal operating temperature (which would take into account ones driving style), or "O's" all around in the morning>?
I assume the latter, but thought I would check in and get some clarity.
Much thanks
Anyway, prior to getting this car, I was always under the impression that tire pressure should be checked in the morning, when tires are cold, and I used a very good gauge. Anyway, if now relying on TPM given the indicated setting (standard, partial load), should I assume that the TPM should be looked at in the morning as well, and the "fill" function used when the tires are cold? Obviously, as one begins to drive, the TPM is going to indicate (+2 or so), as the tires heat up, which was kind of a neat ongoing monitoring.
So, I was somewhat confused if the general goal was to have "0's" all around when the tires are at a normal operating temperature (which would take into account ones driving style), or "O's" all around in the morning>?
I assume the latter, but thought I would check in and get some clarity.
Much thanks
#29
Nordschleife Master
Cole, I sincerely hate to tell you this, but Gary passed away last February or March. We all miss him and his legendary informational posts. He is a legend here, and always will be!