Don't do it!
I had an '83 Audi 5000td for 10 years. This motor is not intercooled and it was VW/Audi's first attempt at a turbocharged motor. The key is to watch your oil temperature gauge and what it is doing. There is a "normal" range that the temps sits at, I believe its at 90 C or 195 degrees, which is the first "tick" mark on the gauge. If you drive over about 60 to 62 mph, the needle will come off of that mark and that means your oil is getting too hot and creating problems with your engine.
This car is very heavy, especially for a 2.0 litre motor, and it was designed for when the speed limit in the USA was 55 MPH. You push it much harder and you will have problems. These motors will crack heads betwen the valve seats if run too hard or used for trailering. Even trailering my 2 550 jetskis was too much for my CA Audi 5000 td.
Drive it around town, drive it on highways to 62 or 3 indicated MPH, but if you want the car to last, don't do 75 in it, the tranny is only an "E" 3 speed, and running it much past 2800 RPM continous will heat soak the motor due to no intercooler.
Also, I strongly reccomend that you change out your oil and get MOBIL 1 Truck and SUV 5W-40 at Walmart, as well as use original Mann oil filters.
The Fram 2487's are junk and don't filter out enough, they should be avoided at all cost.
I usually saw 32 to 34.5 mpg in my Audi, I think it had about a 550 to 600 mile range per tank. Still miss it, it was a great ride.