None of our current people have done a 3800. You may be of more help than finding help here. Flyboy81 who's a registered forum member built his Formula with a 3800SC that was supposed to be < > 400 hp. He just had initial problems of keeping everything together under full power. Robbie of the East Tennessee Fiero Club told me that the car would burn both back wheels at 60 mph.
I think the TDC engine has a pretty high rpm range and produced 210 hp at about 5200 rpm, so it would probably go 6000 to 6500 for the red line. Torque was up about 225 lb-ft, I think. I don't know how much goodies you can find for the engine, but from what I read, the timing belt is a major job and even changing the cockpit side plugs is a problem because of how they are placed down inside the valve covers. It requires either lowering the cradle, or at a minimum, tipping it in order to get a spark plug wrench and extension into the hole because the hole sits right under the bottom edge of the rear glass.
The 3800 is more plentiful and even the 3800 NA starts at about the same hp as the TDC engine. The 3800 SC is 240 hp without any mods. Lots of aftermarket stuff for that engine and they are more plentiful.