93 Octane tuning Q's...

[98 Saleen Cobra]

Hey guys so my car is currently in CA and will be getting tuned for 93 oct that I have here in AL.. I have a couple of questions on what some people are running as far as boost and timing on 93 octane?? Right now I'm set up for15psi and I want to know what is a safe boost level and timing level for 93 oct?

 

[2001Snake]

I'm running 18* on 18-19lbs with 93. I would think 17-18*'s would be good on your set up.