well the VLT had a T3 as well, they come on boost around 2500rpm with a big front mount cooler, on a 3lt so be a bit earlier on a 3.8lt, only really effiecent on stock boost of about 7psi.
7 psi would be a great power upgrade, but what about when the power bug hits, it really isn't cheap to put a turbo on a stock motor, IMO, it's cheaper to do an engine convertion, and will be something different, if u do most of the work urself.
gotta think of diff and gear box and brakes, thats where other expences come in that u forget about and have no budget for.
if u go an engine transplant, for instance, an RB26DETT is or even RB25DET both motors are good for 600hp unopened, u give ur car to a performace work shop and 10g u can get a bolt on turbo system for ur VT, or u can get a RB25det conversion which can be doing great power gains with little effort, like a bigger turbo/s, injectors and intercoolers. For 10g u should be able to get motor/gearbox/cooler/piping/exhaust/AM ECU. drive in drive out or for 10g u can put a turbo on your current car with a tune/FMIC/Piping/exhaust and not much u can do once your there because of weak internals and high compression, so would then need a rebuild to get motor power. either way, nothing what i just wrote really makes sense lol!!!