Hi all,

So, I have 2 tire pressure gauges and both of them read a different pressure than the TPMS in my '07. When I go and let out some air (they are reading high) the + value changes on the display..Then, when I go to let out some more air, it reads a different value (higher).

I have read that the TPMS in the 997.1 isn't the most accurate. This is obviously the case with my car.

2 questions: Is this a warranty-able issue? Or, is it just an unfix-able quirk of the car?

And, what gauge should I buy that is really accurate? (so I dont have to second guess anymore).

Thanks all in advance!

Steve

 

I have the same problems with my TPMS. From what I have heard, it's just not the best system on the 997.1, so I rely heavily on my tire pressure gauge. As for a recommendation for the gauge, I use a Moroso and find it to be very accurate and very easy to use as it seals tightly with the valve stem and has an effective bleeder valve.

 

Can the Moroso gauge be calibrated?

 

Not sure, but I don't think so

 

Do you know of a gauge that can be calibrated?

Also, what is the optimal tire pressure for me to be running.

Mostly city driving, stop and go, hardly ever on the freeway, never track my car and 85% of the time I am alone. Wheels are 19's. 235 in the front and 295 in the rear. The tires are whatever Porsche has OEM, Continental (cant think of the model number off hand)

Thanks!

Steve

 

There is a Moroso gauge that can be calibrated. Model 89562 if you are willing to spend $150 on a gauge. The analog gauges are also more fragile. Note that there are less precise Moroso gauges (2%) which are not very good.

The digital Accutire gauges are also quite good, accurate and precise (0.5%) and more rugged. This Accutire gauge is quite good. They can be calibrated in ref to atmospheric pressure. The usual issue with gauges is accuracy (bias error) - i.e., how far from absolute reference.

 

I generally drive alone and I am running 34 and 39 on the 19 inch oem tire sizes

 

Porsche N-rated tires cold pressures are:

19" 997.1 - 33/39 PSI
19" 997.2 - 34/39 PSI

for light load - up to 2 people little luggage.

 

I'm using this by Longacre.

http://www.longacreracing.com/catalo...d=1118&catid=8

As for pressures, I personally like to run 36(f) 42(r) in my car.

 

If those are cold pressures what are they when the tires are hot? 40/46? Too high.

 

Why so high?

 

I prefer the handling at those pressures, and the regular pressures recommended ....I just do not presonally care for the sidewall wear when you push the car a small bit.

(Now, when I plan on a highway drive I do lower them, taking into consideration the heat). I prefer to keep the rear below 44 if possible and fronts below 40 when hot. (I keep the longacre and a portable battery compressor with me whenevery I do the local mountain drives.....etc).

But when driving locally (and again, mostly mountain area driving) I always watch the temps and they seem to do fine. (I have the OEM SO2's on mine)

Considering Porsche recommends 33/39 (light)........and then 36/44 (loaded)...... my 36/42 is within their specs anyway......

 

I guess my preference is comfort over handling...considering its a car I drive on the streets of LA daily...