I have a ap2 with a supercharger kit on 10lbs on 91 and was wondering what my af should be at?? What's safe?? And what's to lean??

 

Mid 11's is usually good

 

There is a range that is safe, typically on a SC car I tune for 12.5-12.8 WOT from 2500-5k rpm and start introducing more fuel from there to redline, say low 12's to rich as mid 11's on the most conservative side. You can get away with a learner afr on a SC car because it makes less boost over the rpm range, building boost as the rpms rise, its more forgiving and you can/should take advantage of a more efficient combustion where you can. 91 is a little more volatile and running richer does help keep combustion temps cooler which can be safer. 10psi is in no jeopardy of running into detonation issues if your timing is set right, still pretty conservative so you shouldn't have to run overly rich sacrificing some throttle response and economy.