Tee Bee Aych, you'd be better off telling your SC12/14 to fuck the hell off and run a more efficient supercharger. Unfortunately I can't find a map for them to show how shit it'll be running at 15psi, but you are definitely pushing it well out of its comfort zone.
The screw type supercharger found on those Mazda thingies would be a much more suitable unit. Still 1.2L/rev, but are a hell of a lot more efficient at those pressure levels. Less heat, and less engine power wasted on spinning it = more power at teh weelz