Buick V6 Turbo cuts out at high boost ?



I recently purchased a a 1977 Triumph TR7 with a Buick V6 Turbo Conversion. I believe the engine to be out of a 1980 Regal. I'm running a T50 tranny as well. The car also has a 4 barrel Rochester Quadrajet carb. Here's my issue. The car idles erratically from 500-1500 rpms at will. No matter where
I do set the idle in the beginning,but it still does this. Now my biggest issue : When the car is idling, the Boost gauge shows a 20 on the left side if the gauge. When I accelerate at
full throttle in any gear, the boost hits 5-10 and the car cuts out until I let of the gas at least halfway. If I do this, the boost
stays around 10 and functions fine. I can hear the trubo whine like normal, but the problem is driving me crazy. Is there a Buick
Turbo Nut out there that can help me ????
Also, could you tell me the HP of this engine ?,and if the gauge should read on the left side when Idling. Thanks in advance. Ryan / Denver, CO
Buickman, I'm going to also place this in the "before black" tech section, since that's the pre-1984 turbo regal tech section! You may get more answers there!