12's are definately possible on the HRC super 16g at around 24 psi. I'd say with slicks, your goals of low to mid 13's are definately possible with 18 pounds of boost.

As far as the regulator is concerned, the best of the best is the Vortech SFMU with the optional bleed valve. It is the most versatile regulator out there allowing you to change the idle/static pressure, WOT pressure, and rise rate to fit whatever setup you have.

Matt
1995 Eclipse GS
2.0L, S16g Turbo, 8 Injectors, 26psi

1998 Eclipse GSX
2.3L Stroker, AEM EMS Converted to Speed Density, FP3065 Turbo, 35psi , and so on...