Audi Revamps S4 Engine; Adds Horsepower, Torque

Audi unveiled changes to its 2018 S4. The automaker reworked its 3.0-liter turbocharged gasoline engine, raising the power output so that it now cranks out 354 horsepower and 364 pounds-feet of torque. The powerplant features a broadened torque curve. It is also more responsive.

A few years ago, when you thought of performance, the first thing that popped into your head was the size of the V-8 engine. And, of course, you asked the usual questions: “How much horsepower was available?” “How much torque was available?” and “What was the 0 to 60 time?”

Big blocks, small blocks, the size hardly mattered as tuners – amateurs and professional -- massaged cylinder heads, cylinders, manifolds, exhausts and the like to extract every bit of performance possible. Latching onto blower technology, the tuners added huge superchargers and turbochargers, while also playing with fuel injection.

Open Season For Engine Tuners

It is a situation that began as far back as the 1930s and continues, especially at drag strips, across the country today. The fact is that the tuners have achieved some very impressive results. They have taken automotive engine technology to such extremes that 1,800- or 2,000-horsepower engines are routine at dragstrips. On the road, factories are routines cranking out performance machines, the Hellcat by FCA comes to mind, that put out 760 horsepower routinely.

The same applies to the all-new 2018 Audi S4. The S4 design team, combining enhanced performance and benchmarking technologies, with a more dynamic design, has developed a vehicle that pulls 354 horsepower and 369 pounds-feet of torque from a 3.0-liter V-6 powerplant. The engine development team massaged the 3.0-liter turbocharged gas mill and re-engineered it, increasing the power output by 21 percent.

The revised powerplant now features a broader power curve. Power now comes on as low as 1,370 rpm and tops out at 4,500 rpm; the broadened curve means that the 3.0-liter engine has mor get-up-and-go in each gear throughout the engine’s acceleration range. Audi has replaced the supercharger that been used with a turbocharger. The turbo helps manage exhaust flow to the turbine with a twin-scroll housing design.

For 2018, the S4 features a standard eight-speed automatic – Tiptronic®. The Tiptronic® automatic is well-suited for the new V-6’s low-end torque. It makes it possible for the engine to remain near its ideal engine speed.

Audi Quattro System Installed

Audi equips the S4 with its proven Quattro® all-wheel-drive system. The AWD system allows drivers to experience precise handling as the power is dynamically moved between axles as conditions change. The S4 also comes equipped with a sports rear differential that further refines handling by splitting available torque to the rear wheels even further. The additional ability to direct nearly all the torque to one rear wheel maximizes the S4’s driving dynamics. It also enhances one’s driving experience.

For 2018, the S4 features some chassis and suspension improvements, including:

• A redesigned five-link suspension that offers more precise handling and stability while also offering a comfortable ride.
• A redesigned steering rack whose placement at the wheel centers enables more precise steering and handling
• Standard Audi drive select with four drive modes, comfort, auto, dynamic and individual. The selections let the driver change shift points, steering, throttle response and available damper control. It also enables adaptive cruise control adjustment.

Adaptive Suspension System

• A sports adaptive damping system with a new suspension control unit as part of the S Sports Package. The unit is the control module for the suspension computer. It also houses the suspension and damping unit control software plus sensors that measure acceleration rates.
• Dynamic steering which offers a variable steering ratio that adjusts based on vehicle speed and Audi’s drive select setting. At higher speeds, the system improves straight-line stability. At lower speeds, a more direct steering ratio helps improve steering response, increasing making maneuvering easier.

Source: Audi
