When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
so I set my cold tire pressure at 33/38. Drove around for a while then got this. So if my goal is 33/38 cold, do i need to lower the pressures in the driver front and both rears? Put another way, are those readings the cold pressures? Thx.
Tires will heat up anywhere from 2-4psi each from street/highway driving in my experience so your hot readings look normal. After you set your cold pressures I would check what the onboard pressure reading is when you first start driving just to calibrate your manual pressure gauge with the onboard pressure readings. Also, we are figuring out through the course of this thread that you may actually want to be at 29/32 rather than 33/38 unless you’re driving over 165mph with any regularity.
so I set my cold tire pressure at 33/38. Drove around for a while then got this. So if my goal is 33/38 cold, do i need to lower the pressures in the driver front and both rears? Put another way, are those readings the cold pressures? Thx.
Did you reset your TPMS when you adjusted your pressures?
Did you reset your TPMS when you adjusted your pressures?
I don’t think I did. Measured and set tire pressures with gauge and then drove it for a a few miles. The original post shows my readings prior to lowering pressures. Did I need to do something specific to reset tpms?
I don’t think I did. Measured and set tire pressures with gauge and then drove it for a a few miles. The original post shows my readings prior to lowering pressures. Did I need to do something specific to reset tpms?
I live close to the center of Houston. Unfortunately the roads are in poor condition, due to a confluence of clay soil, heavy rains and large temperature difference, in addition to poor maintenance. I did not see this discussed, in addition to load. Pressures towards the full load, help with bent rims. I have kept the full load pressures across my 996, 997, two 991’s and the current 992, with no bent rims. I will say, I have had some slight center rear tire wear, but nothing out of line.
Just came back from a couple laps of our local Nurburgring and the improvement with the Comfort Pressures is pretty dramatic. There’s the expected improvement in ride quality especially over uneven/broken pavement and squared edged hits - as dramatic an improvement for both as going from Full Load to Partial Load) - but also improvements in on center steering and steering feel not to mention a “stickiness” in the rear end that inspires extra confident in corners. The light, floaty feeling that I thought was inherent to the 911 is gone now. The only downsides is that is that I felt PASM (Sports Plus) grab the inside rear brake a couple of times in tight corners to rotate the car, and my already poor gas mileage is likely to get worse at these lower pressures.
I'll keep extolling the virtues of comfort pressures until the masses realize that performance isn't diminished, it's improved. 😜 Glad to have found another convert! LOL
I'll keep extolling the virtues of comfort pressures until the masses realize that performance isn't diminished, it's improved. 😜 Glad to have found another convert! LOL
Hallelujah, brother! I shall go forth and preach the good pressures now. It's sad that so many owners get a diminished driving experience because Porsche's lawyers triumphed over their engineers.
The +/- pressures shown on the app is the difference between your car’s latest pressures reading and the actual ones that were recorded when you last reset the TPMS. It has nothing to do with the “target” pressures selected.
From the screenshot you show, it seems your tire pressures were at 38psi front and 40psi rear when the TPMS was last reset.
Not sure how I missed your post the first time through, but everything you posted above is incorrect. The +/- values in the instrument cluster and the app are temperature compensated deviation from those specified per the settings in the PCM. The TPMS 'relearn' that occurs when you toggle between tire types in the PCM merely tells the vehicle to look for tire sensor position after being rotated and/or swapped out. It has absolutely nothing to do with 'calibrating' the values reported.
Not sure how I missed your post the first time through, but everything you posted above is incorrect. The +/- values in the instrument cluster and the app are temperature compensated deviation from those specified per the settings in the PCM. The TPMS 'relearn' that occurs when you toggle between tire types in the PCM merely tells the vehicle to look for tire sensor position after being rotated and/or swapped out. It has absolutely nothing to do with 'calibrating' the values reported.
Try it out. Adjust your tire pressures to a different value than the ones prescribed in the PCM, then reset the TPMS and see what it says.
I used to run 32/36psi F/R on my car, which is +2 psi front and +1psi over the comfort pressures for
my car. I reset the TPMS with those pressures and the TPMS on the dash and in the app would have me at 0psi deviation.
I'll keep extolling the virtues of comfort pressures until the masses realize that performance isn't diminished, it's improved. 😜 Glad to have found another convert! LOL
Hi CZS,
So are you at 29 - 32 on your 911 ? I'm going to set to those numbers today and try it.
Ok.........I dropped my pressures this morning to 29 - 32 and drove down the street so the system would measure or show the pressures, what showed is in my first picture 30 - 33. Then in my second picture you can see "Pressure Deviation" which totally confuses me. Based on what the values are in my pressure deviation, do I need to enter or change something?
Ok.........I dropped my pressures this morning to 29 - 32 and drove down the street so the system would measure or show the pressures, what showed is in my first picture 30 - 33. Then in my second picture you can see "Pressure Deviation" which totally confuses me. Based on what the values are in my pressure deviation, do I need to enter or change something?
Thanks
You're absolutely fine. 30/33 is where I set mine. Keep in mind the pressure deviation rounds to the nearest PSI so it's entirely possible (likely even) that you're only "off" a fraction of a PSI. My guess is the ambient temp was over 68F when you adjusted the tires so the PCM is wanting a bit more air to compensate. If you want to really dial it in, add/subtract 1PSI for every 10 degrees over/under 68F when you adjust the tires. Should put you in alignment with the PCM algorithm.
How did you like the feel of the car with the lower pressures?
You're absolutely fine. 30/33 is where I set mine. Keep in mind the pressure deviation rounds to the nearest PSI so it's entirely possible (likely even) that you're only "off" a fraction of a PSI. My guess is the ambient temp was over 68F when you adjusted the tires so the PCM is wanting a bit more air to compensate. If you want to really dial it in, add/subtract 1PSI for every 10 degrees over/under 68F when you adjust the tires. Should put you in alignment with the PCM algorithm.
How did you like the feel of the car with the lower pressures?
Thank you SO much!! Totally different road feel felt immediately. The car is in Naples FL, the outside temp when I adjusted them was 77, and I adjusted the pressures with a very accurate gauge that I've used and tested against other gauges it it seems to be very accurate.
How is tire wear at 30 - 33 ? I know historically the rears wear faster...But I'm wondering how lower pressures affect wear.
Thank you SO much!! Totally different road feel felt immediately. The car is in Naples FL, the outside temp when I adjusted them was 77, and I adjusted the pressures with a very accurate gauge that I've used and tested against other gauges it it seems to be very accurate.
How is tire wear at 30 - 33 ? I know historically the rears wear faster...But I'm wondering how lower pressures affect wear.
Thanks again!
Tire dependent probably. But my last set I was on Goodyear F1s at 29/32psi and it lasted about 21k miles. I've since switched to Michelins and boosted to 32/36psi for a little bit more response.
07-27-2024, 04:56 PM
