[Lightngsvt]

My car was built with performance RFT's, but I had non-RFT performance A/S mounted before delivery. The car now seems confused, it can't tell what tires are installed. The sticker in the door jamb says 38psi all around, I asked Tire Rack and they say to use factory inflation specs since the tires are the same size. IF I set the car to Winter/AS it wants to see pressures at 42/46 which seems way too high. When I set it to Manual it'll show me the pressure but no recommended PSI.

Nutshell, should I leave it set to manual and follow the posted recommendation of 38psi? Or go with the higher psi and set the car to Winter/AS tires (I realize it doesn't affect anything other than this setting)?

[mechman]

Originally Posted by Lightngsvt

My car was built with performance RFT's, but I had non-RFT performance A/S mounted before delivery. The car now seems confused, it can't tell what tires are installed. The sticker in the door jamb says 38psi all around, I asked Tire Rack and they say to use factory inflation specs since the tires are the same size. IF I set the car to Winter/AS it wants to see pressures at 42/46 which seems way too high. When I set it to Manual it'll show me the pressure but no recommended PSI.

Nutshell, should I leave it set to manual and follow the posted recommendation of 38psi? Or go with the higher psi and set the car to Winter/AS tires (I realize it doesn't affect anything other than this setting)?

There is a pretty detailed section in the G42 user manual showing all the recommended tire pressures based on all the potential tire options that the car can be optioned with from the factory.

I imagine there is a similar section in the G20 manual as well.

[jg4c]

Originally Posted by Lightngsvt

My car was built with performance RFT's, but I had non-RFT performance A/S mounted before delivery. The car now seems confused, it can't tell what tires are installed. The sticker in the door jamb says 38psi all around, I asked Tire Rack and they say to use factory inflation specs since the tires are the same size. IF I set the car to Winter/AS it wants to see pressures at 42/46 which seems way too high. When I set it to Manual it'll show me the pressure but no recommended PSI.

Nutshell, should I leave it set to manual and follow the posted recommendation of 38psi? Or go with the higher psi and set the car to Winter/AS tires (I realize it doesn't affect anything other than this setting)?

I had the same issue. Forget the system. The door jamb 38 psi all around, matches the manual 38psi for your set up. Tire Rack is correct.

I replaced the HP summers that came on my car with the same size UHP AS's. I run the recommended 38 and it's perfect. 42/46 is way too high.

[G30M]

thanks for the picture

but all the tires are 225 front 255 rear and the pressures given vary from 32 psi to 46 psi.

i'm confused

anyway i'm running 34 front 35 rear in the 225 front 255 rear summer RFT