Now that Audi has replaced the B8-generation S4, the 3.0 liter supercharged V6 engine has gone by the wayside. Replacing it is a more more powerful 3.0 liter turbocharged V6 in the new B9-gen Audi S4. This new engine makes about 20 more horsepower but also more torque and is far more fuel-efficient. However, despite the increase in power, torque and efficiency, fans still love the older supercharged engine for its sharper throttle response and engine noise. For owners of the B8-generation Audi S4 or S5 with the old supercharged engine, APR has a way for you to boost power up to much higher levels than the new turbocharged engine’s.
The new APR Ultracharger System is essentially a completely revised throttle body system. The original throttle body’s cross-sectional area is 25 percent smaller than the supercharger’s inlet, thus drastically restricting the airflow to the engine, robbing power. Just replacing that with APR’s Ultracharger throttle body system, which is 28 percent larger than stock and even larger than the supercharger’s inlet, you can see gains by as much as 33 hp.
When this Ultracharger System is combined with APR’s Supercharger and Crank Pulley kit and included Stage II APR ECU install, the 3.0 liter TFSI engine can make up to 542 hp, on race 104 octane race fuel. On 91 octane fuel (Premium/Super in US), that combination will make around 478 hp, which is still a crazy amount of power for the B8 Audi S4 and drastically upgraded from the car’s stock 333 hp.
So if you still own a B8 Audi S4 or S5 but want some more power to compete with the more modern sports cars on the market, this APR Ultracharger System seems like a great way to go.