Senner Tuning has prepared a second performance package for the new Audi RS5, and as you might suspect, the power level on the German coupe has been further increased.
This means that instead of 450 HP (331 kW) and 430 Nm resulted from their previous upgrade, the Senner Audi RS5 is now able to deliver 506 HP (372 kW) and 478 Nm of torque, due to its new valve-controlled stainless steel exhaust system with zero-pressure monitoring.
These new output figures enable the Senner Audi RS5 to sprint from 0 to 100 Km/h in 4.2 seconds and reach a top speed of 300 Km/h. 
At the exterior the Senner Audi RS5 has been enhanced with a new set of 20 inch, diamond black polished alloys wrapped in performance tires, carbon fabric mirror cases plus additional front grille and window frames. Optional carbon fiber and leather interior customisation is also available.
The Senner Audi RS5 price is around 113,900 Euro, which means 18,900 Euro more than the stock version.
Senner Tuning press release :
MAXIM À LA Senner Tuning – Audi RS5 with 506 hp and 478 Nm
The experienced team of the Senner Tuning AG Company from Ingelheim
willingly undertakes any possible challenges. This time it was an Audi
RS5 again – undertake a great power increase – the most powerful version
of the model. And as Benno Senner never leaves things to chance, there
was not an unexpected result.
The Bilstein coilover kit, called B16 PSS10, allows for 10-stage
adjustable damping in both the compression and rebound cycles. For the
demonstration purposes, different left and right rims of the vehicle
were coated with respective coating: diamond black polish in dimensions
of 9.5 x 20 inch at the front and 11×20-inch at the rear. Driver side
spider SC1 and passenger side Varianza T1S admire everyone with the
Vredestein Ultrac Sessanta (XL) front 255/30R20 and rear 295/25R20
wheels.
To increase performance, the valve-controlled stainless steel exhaust
system was added, and zero-pressure monitoring was adjusted. As a result
of such modification, the 4.2-liter V8 FSI engine, which has already
provided 331 KW / 450 hp / 430 Nm ability, accelerated from 0 to 100 km /
h in 4.6 seconds and provided an electronically limited top speed of
250 km / h, now provides 372 kW / 506 hp / 478 Nm and a sprint from 0 to
100 km / h in 4.2 seconds. The maximum speed limit has been raised to
280 km / h. It is possible to reach even 300 km / h, of course, only
with changed tires.
In a kind of elegance, the outer shell of the Audi features mirrors in
shiny black 245 carbon fabric, additional front grille and window frames
in the Black Edition. With regard to the electronics, it should be
mentioned a power converter for amplifying the electronic gas signal and
the possibility of DVD-activation while driving.
In addition, optional carbon fiber and custom leather trim are available on request.
The total cost of the complete vehicle is about 113.900 €, the cost of
reconstruction is 18.900 € including taxes and TÜV-registration.
Incidentally, Senner Tuning AG also gladly assists in the purchase of
new vehicles, and also addresses issues with regard to financing and/or
leasing.

Source: Senner Tuning