Booster bad?

[demian5]

My truck runs like I have a vacuum leak. The booster feels like it has some sort of boost, however when I pinch off the booster vacuum hose, the truck idles down a bit and the brakes feel like manual and require a ton of foot pressure to operate.

Right now, the truck idle has to be set to a point where the air fuel mixture screws don't effect the idle quality (it actually sounds weird at idle like its struggling to run off the idle mixture screws, almost like a puff puff sound). Off idle, perfect runner. No surging or anything. The only other vacuum line is going to the trans, and I pinched that off with no change in idle.

I just replaced the intake manifold gaskets because the exhaust crossover areas were blown out and it had an exhaust leak at the intake (that's a new one for me). It idles the same before and after, just quieter now...

Its basically a stock 350 with a turbo 350.
Has an edelbrock Q-Jet Carb that I pulled apart and cleaned it up (wasn't dirty).
MSD billet distributor with MSD blaster coil (no ignition box) set to 10+ BTDC in park at 700 RPM. I removed the vacuum advance hose and capped all the vacuum ports off.

Maybe someone has some insight. Thanks.