The 30/30 cold worked for me, too, at the track (Corsa III's). The street
is actually trickier since you can't guarantee getting heat into the tires quickly
or even consistently. I hate hard tires and a softer tire has a larger contact
patch, so I tend to run 'em a little softer than most. Try 29 psi (cold) on the
front and see what you think... it has worked well for me. A softer tire flexes
more and comes up to temp better in the intermittently curvy roads around
here. While you can overheat a tire at the track and make it go greasy, it
is much more difficult to overheat on the street, where the twisties tend to
come and go, or just not last more than a few miles.
The rear can be heated up just by hard acceleration, so a cold starting
pressure of 31-32 seems to work well on the street, though I sometimes go
lower depending on the weather, the type of riding, sun spots, what mood
I'm in, etc.