91LX is correct.
The tranny will probably take it for a while better that the short block.
I've seen guys runnin 9-10 lbs of boost OK for a while, but eventually it gets nasty, and its time to pull the engine...
I'm a big believer in the 8lb boost limit for centrifugal blowers on near-stock (ie no engine work) setups. I've had mine for over 2 years now runnin day in and day out. Not even a hiccup....
I would go with either the Vortech with aftercooler or a Procharger with intercooler. Both have proven records on the street and track, and my experience with the Procharger has been quite good overall.
The key is to get a good tune and don't get too greedy!!

__________________
Uncle Sam
"What the hell is up with all the gauges?
Calling Captain Kirk, your ride awaits... Phasers on stun...."