The Audi 4000 Quattro came with a very simple motor:
Audi JT

-2.2l 5 Cylinder Naturally Aspirated 115 HP

- 8.5:1 Compression

- 5 Window Distributor Ignition (1 spark per Window)

- CIS Fuel Injection (Bosch Mechanical)
In order to turbocharge the motor, we're taking components from an Audi Ur Quattro
Audi WX Motor

- 2.1l 5 Cylinder Turbocharged 160 HP

-7.0:1 Compression

- Single Window Distributor ( Spark controlled by ECU timing determined by flywheel position and speed plus distributor window which gives Camshaft TDC, with adjustable Spark Map based on Boost/Vacuum)

- CIS Fuel Injection (Bosch Mechanical) with Boost Enrichment

The JT did not have the provisions for the sensors and equipment for turbocharging, however, Audi didn't change the overall block layout from the turbo to the non-turbo, the only real differences is what got drilled/tapped and what didn't.

I had to build a single window Distributor, as well as drill out the sensors for the crank position and crank speed, and drill the flywheel to add a pin for crank position set at 60 degrees before TDC, and then custom set the depth for the hall induction sensors.
I also had to splice/replace the engine wiring harness to accommodate the MAC-02 ECU, which primarily drives the ignition timing and provides some minor emissions controls.