F1A with a 4.5 pulley is the largest you can go it will make about 14psi*.
House of boost is who I went through. Those guys are great. Race bypass valve is strongly suggested. I would also suggest the race air to air intercooler. These are my opinions based on my experiences and nothing more.
http://www.camaro6.com/forums/showth...&highlight=f1a
http://www.camaro6.com/forums/showthread.php?t=506456