Took her around the block a few times for the first check ride after many start-ups in the driveway to tweak and adjust stuff. Got on the gas a couple of times just because I couldn't help it. Awesome by the way! Anyway when I got back home the brakes locked up,pedal was down and wouldn't come back to normal position. I've got a brand new brake booster (stock). I disconnected the vac line from the booster and the brakes released and acted normal.Just wondering if anyone else had this problem. I've got a 1990 gmc xcsb with a 2003 5.3 4l60e out of a silverado. Also a car intake and a corvette cam. Just a mild street build. My booster hose is hooked up to the large port at the rear of the car intake. Is my engine making too much vacuum for the stock brake booster? My vacuum guage reads a steady 19" of vac. Thanks guys for any assistance.