Is it me or is the factory reommended tire pressure for the rear tires (44psi) insanely high for street use? Anyone else lower it?

 

It's high because of all that weight in back. My Honda Shadow Cruiser motorcycle has a similar layout: 31/41, because more weight is in back.

 

took deliv of the 997TT thursday....porsche in all of their wisdom didnt have the cold PSI set properly. it was 31F 37R when it should be 37F 44R....well basicly, alrdy need a new pilot sport tire on the left front....wheel pinched the sidewall.

 

In the manual, 33/39 is the factory recommendation for a partially loaded car.

 

Great, I'll go with that. The sticker on the door jamb only has the higher pressure listed.

 

Those are for full load only, you don't want to be driving with pressures that high. I run 33/39.

 

My car came with 35 all around. I never thought the front and back were different. thanks for the heads up.

PS, what is right? 33/39, 37/44?

 

You would think if the pressure were so low to cause damage to the tire that some kind of warning would have been given by the TPM sensors. Is the dealer going to replace for you - warranty??

 

BTW, the PDI guys from my dealer set it at the higher setting.

 

When you are driving alone, 33/39 cold pressure is right.
When you are driving with 3 girlfriends in the car, then 37/44 is better...

 

Try it both ways, you'll notice a difference in the ride quality. The lower setting is for 1 driver, not too heavy, and no luggage. I split the difference and run 35/41.5 unless I know I am going to be alone and on a poorly paved stretch of road in which case I drop down to 33/39. It's fun to watch the temps come up as the tires warm up.

 

3 Girlfriends? Are 2 of the midgets?

 

ok, well went to the dealer today, they are most likely going to replace the tire for us free of charge. We bought that protection plan for tires/wheels. ill see what they have to say about 33/39 then

 

Hey Guys,

So I had a real interesting experience a couple weeks ago. I went to STUNT DRIVING SCHOOL. Which means, I leared to do 180's, reverse 180's, box park, and a couple other tricks, it was pretty awesome.

The instructor is a guy named Bobby Ore, and is a legend in the community. He is an expert witness regarding vehicle dynamics, tire pressure's, etc.

Bobby took a long, long time, explaining to us, how to set the proper tire pressure on the car. His answer was VERY simple. Set tire pressures to the MAX pressure the tire can handle. This will give you, even wear, more grip, no need to ever balance and rotate and the tire will never "roll over."

Now this setting is in direct contrast to the tire manufacturer who wants you to use your tire safely, but also wants the tire to wear out, over time, so it needs to be replaced.

Then there is the car manufacturer who wants a different tire pressure to make the ride, ultimately the most comfortable for the passenger.

-- So when it comes to tire pressure settings, all three of them are right.
1) Bobby:
Max air = better road feel and feedback of tire. More surface area equals more grip and less deteriation of the tire.
CON = A VERY BUMPY RIDE.

2) Tire Manufacturer: better balance between comfort and wear.
CON = Tires wear out sooner and need to be replaced $$$

3) Auto Manufacturer: Ride is most comfortable but does not take into account the longetivity of the tire.

So ultimately, the conclusion I have come to is, there is no specific, defined, answer for tire pressure. There is WAY TOO LOW and WAY TOO HIGH but everything in the middle of those equations are fair game.
Again, what are you trying to acclompish with the tire, longetivity? performance? comfort? -- it's all a balancing act.

(for the record, i will take tire wear instead of max pressure, I just don't like the ride being that bouncy.)

B

 

B,

I don't think Bobby Ore would be a believer of max tire pressures if he did a 180 in the middle of turn 1 at TWS going 130 mph, and experiencing corded tires in the middle of an enduro might also sway his opinion. I don't think the stunt drivers use pyrometers on their tires, rather on their flame suits