My car ran 11.53@118 and I wanted to run high 10's stock appearing so I tore the motor down to pocket port the heads. When I got the heads off, I couldn't believe the car had gone 12's let alone mid 11's. The heads were full of ridges of casting flash and mismatch and the port shapes were 1960's. awful.
I also have a TTA so I figured while I was porting stuff, I buy a set of those heads to pocket port and put big valves in. Someone on TB.com was selling NOS TTA head sets for like $200 shipped, so I bought a pair. Those heads (basically FWD 3.8L heads) are WAY better. They were designed by someone who kind of knew what they were doing and cast by someone who gave a crap.
Only 3 years was a huge leap and 3800 is way beyond that.
The Buick V6 was a pig off an engine that responded well to boost and EFI, but you cannot change a pig's nature.
And this is why I sold my Turbo T back in the Spring and am focusing on LS-stuff going forward. The LS platform in its worst confirguration is a fantastic starting point for a performance build.