I have a 2006 Boxster S and it tells me to put 30 psi in front and 37 psi in back.
Ive noticed the tires can feel very different depending on the outside temperature.
For instance I filled up the tires to spec a week ago when it was in the 40's then here in NJ the weather went to 90s then dropped back to 60s.
Tires felt to hard when in 40's felt really perfect for 2- 3 days during the 90s. then became very mushy when it hit 60s.
I stopped by the gas station yesterday when it was in the 60's to put in more air.
But the meter tells me that the tires are still 30 up front and 37 in the back.
What is going on???? should i up the psi when the temperature is hot or cold?

 

You should check tire pressure when it's cold. Do it in the morning before you go for a drive. Of course changes in temperature will affect tire pressure, that's completely normal.

 

i do go straight to the gas stationg in the morning which is less than a mile from my house.

but what temperature is cold? if it is 60s outside and i cant do anything about it?

does it make sense to bump up the air pressure by 31 38? does anyone do this? custom set your air pressures?