tire pressure vs temperature
 

Hi,

this is purely for my education and maybe someone here knows the answer.
So I bought an aftermarket Tire Pressure Monitoring System from tirerack: http://www.tirerack.com/accessories/detail.jsp?ID=55

The thing works great and already saved me once by alerting me to a slow flat caught by catching yet another loose nail on the street :mad:

Well, this thing not only measures pressure but also temperature.
When driving on the street I have the pressures according to spec:
29 front 36 rear

Now I notice that when I drive the pressure goes up by around 4 ~ 5 PSI equally on all 4 tires but the TEMPERATURE (when the tires are warm) is usually 10 F higher in the fronts than in the rears.

No I am not worried about it but would like to understand it:
If I want to inflate my tires PERFECT should they have the same temperature front and back or not?

Opinions please

Tire pressure vs temp
 

The way I understand it: front tires steering and braking in normal street driving will increase the temp more than rear -- but on the track you may/could see more equal temps. The more important temp is across the tread from inside, middle and out (tells about alignment and correct pressures) This takes the other tool - pyrometer.

IMHO the only thing the remote sensors are used for are low tire pressure and thus overheating of that tire so you know to get it fixed.

The spec Boxster pressures (29/36) should be set cold and will normally raise 3-5 pounds with driving. The raise in temp difference between front and rear should be accounted for in the Porsche spec (?) I would think... :rolleyes:

Take care,
Ed
PS: How are the MOMO's working out?

I agree with sboxin. Front tires see much more loading in street driving than rears. They should get hotter. Also in the Boxster you have to realize that the radiators will heat the front tires as they are located right in front of them. Finally consider that the front brakes absorb 70+% of the braking load and therefore get much hotter than the rears. This heat transfers from the rotors to the hubs to the wheels to the air inside the tire. All in all it is normal and expected that front tires get hotter than rears.

Hi Ed,

thanks for asking, they worked out GREAT :D

Thanks again

yeah, that makes sense
I noticed that on the track where after each session the high temperature alarm goes off for the fronts because of the hot brakes