hmm... i think RSR's should be run at lower pressures... maybe around 28-32 HOT... 595s slightly higher 30-34 HOT.... That's for getting max grip, but you will trade off some handling... Higher pressures makes the car less grippy but more responsive... if your starting out, good idea to use higher pressures first... better handling will do you more good than grip... once ur completely happy and confident with the handling at the limit... drop the pressures... you will notice the increase in grip...
If u dont have a temp guage... use ur hands.... if ur pressures are way out of whack... u can feel it... 10+ deg cel is easy to feel with ur hands...
ie. If the temperature on the face of the tread is L60 C75 R55
you will easily be able to feel the centre is friggin hot and cooler on the edges.... clear indicator to drop ur pressures....