I target 40 hot back at the paddocks. Depending on the tire, the weather, the track - I may be estimating between a 5 and 10psi gain after a session. I've run both BFG-R1's and NT-01's and they both seem to get real greasy north 40, especially the R1's.
I've started my day as low as 28. But starting that cold - you have to warm them up (lap or 2 or more) before any fast laps. Then monitor the sidewall or use shoe polish. Unless you have a good pyrometer, not sure it's too useful (yet).
Having said this, at your first event starting higher - even as high a 5psi above MFG rec could be a good thing. How'd it go?
08 E92 DCT31.1 | JTBLK/BLK/CARBON LEATHER | CF ROOF | TP | PP | 18 | MEDIUM CERAMIC TINT | HARDWIRE V1