I've had a bunch of experience building turbo charged Audi 5 cylinder motors and tuning them to over 650hp. (At least one of the Factory motors was at 950 de tuned ie with smaller turbo and different head)
I always thought that the chevy 6 could be fun to turbo charge. The pressurized motors will work better. Boost is hard on crank journal bearings. Audi uses a specific bearing, one shell is one hardness, the other shell is harder. I have seen Audi turbo motors built at home with the wrong bearings, they DO work, for a little while but not long.
Supercharging is probably better since the boost is constant. There is the lack of "Lag". The sudden punch of a turbo is what will kill the babbitt. That said....
Find a turbo that is small, water AND oil cooled, it will last longer. Triple k turbo from an Audi s4 would be a good choice, they are plentiful and have a wastegate in them already.
Jeremy
