Ok so far I have a '89 GXL with a S4 TII drivetrain in it. Now I am replacing the N/A motor with a TII engine. Now I want to run a bigger turbo (T04 maybe) front mount intercooler etc, and I had a few questions. First one is I plan on going standalone. Will I have to use a turbo wiring harness in this case or do I need a custom one? Next is I have a TII transmission and driveshaft hooked up to a modded N/A rear diff. The car is a S5 but the rear diff I scored is from a S4 TII. Will they interchange? Also If I am looking to push 400 hp at the crank will a T04 with a street port be able to achieve that? (with the necessary fuel , ignition upgrades)
And last, will my S5 alternator, water pump and housing, fuel rails and power steering pump be able to work with a S4 TII engine?