OK guys, got the TSB for Run-Flat tire pressures on the SC 430.
TSB: PG005-02, Dated: April 4,2002, Title :Adjustment of Tire inflation Pressure.
Intro: Normal condition for R-F tires on SC 430 to lose up to 1.5 psi/month.
Low Tire Pressure Detectiion: Tire pressure is monitored all the time even with ignition off. When ignition is turned on warning light will illuminate if tire pressure falls below 26 psi.
Temperature compensation: The following figures are taken from a chart, so you will have to interpolate for intermediate temp changes.
The chart is based on difference between actual air temp (either in garage or outdoors) and the lowest seasonal temp expected.
Tires are cold=sitting for more than 4 hours.
EXAMPLE: Garage temp=68F
Lowest seasonal temp=14F
Difference=54F so add 4.6 psi to 33 psi or 37.6(38) psi.
I can't reproduce entire chart so I will just list main temp changes.
Temp Difference between garage and Lowest seasonal
0 18 36 54 72 90 108
Tire Pressure increase from 33 psi.(add the following)
0 2.0 3.2 4.6 6.0 7.5 9.0
Hope this helps and doesn't confuse.
Ron

 

Here's a graph using the figures provided by Ron. This may help your interpolation.

If the graph is not helpful, then maybe Ron can fax me a copy of the chart. I'll make a clean image and post it.

 

Will be glad to fax you the info. E-mail your fax number to me and I'll get it off right away.E-mail to: ron@entercomp.com
Ron