911SLOW

The sensors of the wheels can not be refitted to the race wheels? I have a system not Porsche that you could fit to any wheel. For bbs e88 I had to enlarge the air valve holes a bit.
Just curious

John

mdrums

I considered adding the TPMS to my CCW track wheels but my Porsche dealer told me I would be wasting my money...yep he actually said this...wow...I had to believe him.....he said since I start out with pressures around 26-28psi with hot pressures around 38psi the TPMS will always think I have a flat and the warning lights will be on and TPMS will not work to show real pressures.

This is on a 2009 Carrera S. Anyone? I thought the low tire pressure warning lights would come on when the car was cold but go off when the tire pressure reached 38psi. Anyone with experience with this?

Laertes

Yes, the low pressure warning (a red exclamation point in the tach) does go on. I run TPMS on my track wheels/tires (lobster forks with Toyo R888's) on my '09 C2S. When I arrive at the track, I drop the pressures to 31Fr/32R. I can't remember if I get the warning right away or after I get the tires warmed up on the track. I think the issue is the computer takes the temperature into account as well as the pressure. And the warning is based on what the pressures would be at standard temp, not the high temps we see on the track. In other words, if at track temps your pressures are 38psi (which would normally be within the range of acceptable pressures according to the TPMS) the computer knows that if you don't add air, as the temps come down the pressures will as well and you will end up below the acceptable range. It's a pretty smart system.

After you acknowledge the warning once the temps are up, the error message in the multifunction display goes away and just the red exclamation point persists. The pressures are then re-displayed on the tach screen, and all is good. I find the TPMS to be remarkably accurate (I know it was updated in '09; the TPMS in earlier cars is apparently much less accurate), within 1 psi when compared to my hand held pressure gauge.

As an aside, I personally wouldn't even think about going on the track without TPMS. I find it extremely helpful to keep an eye on my pressures, as the tires get pretty greasy above about 40 psi, and though this is obvious from how the car handles, it is nice to be able to see on the straight that things are getting higher and know that I shouldn't push it too hard on the left hander coming up at the end of the straight. Plus, if I should ever pick up a nail or anything, I want to know things are dropping so I can get off the track before something catastrophic happens......

Polarporsche

I was at LS this pass weekend and running my Forgeline wheels & R6's without TPMS. Only a few lights on the dash were illuminated, the low tire pressure indicator and the red !. No bells or alarms going off.

I'm going to leave things as is, the lights are not a problem.

911rox

Thanx Polar, I may follow suit then bcoz i'd rather put that money towards tyres for the number of times I'll be using the second set...

TRAKCAR

Well, I've always had them and they don't always work but when they do I like it, you can actually see at what PSI they grip the best and when the grip starts to go away.
Plus the above stated picked up nail, badly mounted tires, leaking, bead wire breaking, etc. I saw it all coming with a flat tire warning.
Seems very accurate too when I check the PSI with my gauge.

One solution I am going to try is do 1 or 2 laps come in. Stop the car and reset. Might avoid warning this way.

deputydog95

Good info. Sounds like I should go ahead and put them on them my new wheels then.