Hey I am considering my 1st Audi A6 that is modded. I wanted something solid and fast with room for improvement. What do you think of it?

Its a 2.7 BiTurbo A6 with 6 speed manual transmission.
The car has about 148k Miles and ALL scheduled maintenance
had been done so far, including Timing Belt and waterpump at 128k.
5 matching Wheels and tires (spare is Full Size wheel)
2 tires Brand New others somewhat used, still good tread on them.


Upgrades:
Stage -3 K04, RS4 inlets, 3inch Downpipes No pre-cats or cats, Auxiliary Thermal Switch (198F)
New Auxiliary After-run Pump,R34 TBB, New Battery, MBC, K&N Filter,
Blauparts full suspension Kit (F+B) , with Shocks and Eibach Lowering Kit
R1 Diverter Valves,HID low beam, High Beam and Fog lights, Custom
Headlights, LED All Tail lights, M3 Spoiler lip, New Brakes with
front Slotted Rotors, Tinted windows, built In Police scanner with Radar detectors.

Cons: CEL comes on for P1117. which is O2 Sensor Bank 1 Sensor 2
easy fix i just didn't have time to look at it. otherwise new sensor is less than $50
Soft Clutch
Paint has some scratches but very minimal.

 

Assuming a stage3 chip or flash, there is not a lot more you can do to that car. You probably won't solve the O2 sensor problem without cats, so I assume you are in a no-emissions-test state. My guess is that it may be due for a clutch soon (I chipped at 75k and wore the clutch and FW by 90k). 128K is late for a TB if it was the first, since these should be done every 75-90k. Also, you don't mention the year. 2002 and earlier did not have as good oil feed to the turbos as the 2003-04, from what I have read.


As a further caveat, these cars are heavy + AWD does not = quick. The drivetrain or transmission become the weak points and are damn expensive to fix. As far as fast, with a chip removing the governor you can exceed 150. I allegedly know that for a fact.

 

Edit: Be wary of mismatched tires. They stress the differentials. All tires should be the same dimensions and, preferably, wear in order to keep the circumference the same.