what is the right psi at cold?

 

I stick with the recommendation for 18's, 36/44. 44 is pretty harsh with 19's, but if you live where there are pot holes I'd run 44. I run 42 to take the edge off a bit but SoCal roads are not too bad.

Handling wise I actually think the lower PSI in the rear feels better.

...Joel

 

depends what you are using it for and how you want it to ride. Look at the tire sidewall and see what max PSI is for cold pressure. I usually run about 5 psi lower than this for street use. You can run a lower PSI for a softer ride but have a good chance of running the life of the tire down or blowing out a sidewall for under inflation. For track use (depending on the stiffness of the sidewall) i run them about 28-30 psi the get a soft tire to grip better. Plus the extreme heat a tire will see in track conditions will bring the pressure up significantly.