Survey: Tyre pressure warning system.
12-05-2002, 12:08 PM
#16
Burning Brakes
Any system that has a set pressure as a minimum is flawed to begin with. The use of non-OEM tires, differing driving styles, road conditions, and other factors should be considered when determining 'proper' tire pressure. When a car manufacturer lists the tire pressure for its vehicle it should be as a guideline, not as a requirement.
Alhough Porsche says that my tires should be 36 PSI up front and 44 PSI in the rear, I have found (over 12 years of driving 928s) that 38 to 40 PSI all around works best for me. YMMV.
Alhough Porsche says that my tires should be 36 PSI up front and 44 PSI in the rear, I have found (over 12 years of driving 928s) that 38 to 40 PSI all around works best for me. YMMV.
12-18-2002, 12:51 AM
#17
Electron Wrangler
Lifetime Rennlist
Member
Lifetime Rennlist
Member
My '94 GTS has RDK (just a few early '94's had it before I get a slew of mails on this) its fully functional but does give some grief.
Seems to consistently alarm @ 1-2 psi too low.
I also find that in the heat of summer it alarms more frequently - I think the temperature compensation is not really that good - as well as there does indeed seem to more rapid tire air leakage at extreme temperatures (Phoenix in summer = hot). Two seperate issues - one means the RDK should be especially useful in summer the other means its also a bigger pain then.
So a mixed bag - I think Porsche really screwed up in not creating a system that was externally calibrated w/ ability to reset thresholds for different tires. The whole calibration is manufactured into the phenomenally expensive RDK inserts in the wheel and cannot be reset.
However - how many other options for tire monitoring were there back when this was designed?
New systems from Beru (OEM) & Smartire (a few hundred $ retail)have some good features and 2 level calibration (Loss Warn/Emergency). Always wondered if it would be possible to interface one of these new systems into the Porsche dash display.. don't like extra display junk hanging around - never really gave it enough thought though.
For me its still worth it for peace of mind @ speed
Alan
Ed - check out smartire on tirerack.com sounds like what you mentioned
<a href="http://www.tirerack.com/accessories/smartire/smartire_all.jsp" target="_blank">Tirerack/SmarTire</a>
Seems to consistently alarm @ 1-2 psi too low.
I also find that in the heat of summer it alarms more frequently - I think the temperature compensation is not really that good - as well as there does indeed seem to more rapid tire air leakage at extreme temperatures (Phoenix in summer = hot). Two seperate issues - one means the RDK should be especially useful in summer the other means its also a bigger pain then.
So a mixed bag - I think Porsche really screwed up in not creating a system that was externally calibrated w/ ability to reset thresholds for different tires. The whole calibration is manufactured into the phenomenally expensive RDK inserts in the wheel and cannot be reset.
However - how many other options for tire monitoring were there back when this was designed?
New systems from Beru (OEM) & Smartire (a few hundred $ retail)have some good features and 2 level calibration (Loss Warn/Emergency). Always wondered if it would be possible to interface one of these new systems into the Porsche dash display.. don't like extra display junk hanging around - never really gave it enough thought though.
For me its still worth it for peace of mind @ speed
Alan
Ed - check out smartire on tirerack.com sounds like what you mentioned
<a href="http://www.tirerack.com/accessories/smartire/smartire_all.jsp" target="_blank">Tirerack/SmarTire</a>