奧迪在巴黎車展前發(fā)布了全新的S3，其中最大的亮點(diǎn)莫過于S3裝備的全新2.0TFSI缸內(nèi)直噴4缸發(fā)動機(jī)，無論是221kW的功率還是380Nm的扭矩均創(chuàng)造了同級別之最。這使得全新S3的0~100km/h加速時間僅用時5.1s，比上一代足足減少了0.7s。

  這款發(fā)動機(jī)相比于之前采用的2.0TFSI來說，雖然1984ml的排量以及氣缸尺寸未變，但是幾乎可以說是完全重新設(shè)計的產(chǎn)品。這款強(qiáng)勁的4缸發(fā)動機(jī)裝備有兩根平衡軸以曲軸轉(zhuǎn)速兩倍的速度旋轉(zhuǎn)，確保了一流的平順性。氣門升程可以兩級調(diào)節(jié)，此外還有可無級調(diào)節(jié)氣門正時的裝置，進(jìn)氣門調(diào)節(jié)范圍有30°，排氣門則有60°。
  此外，這款發(fā)動機(jī)的獨(dú)特設(shè)計還有將排氣歧管集成在了氣缸蓋上，這樣做既可以降低排氣的溫度，還可以提升進(jìn)氣的溫度，以提高發(fā)動機(jī)在尚未達(dá)到工作溫度時的效率。全新的渦輪增壓器將進(jìn)氣壓力提升至1.2bar，奧迪同時也對中冷裝置進(jìn)行了升級。
  在全新發(fā)動機(jī)熱管理系統(tǒng)的幫助下，潤滑油可以在啟動后很短的時間內(nèi)就達(dá)到工作溫度，并且可以維持在85℃至107℃之間，確保發(fā)動機(jī)時刻保持最佳工作狀態(tài)。
  奧迪對發(fā)動機(jī)的主要部件也進(jìn)行了強(qiáng)化處理，從活塞螺栓到連接軸均進(jìn)行了強(qiáng)化，鑄鐵發(fā)動機(jī)缸體在主軸承座以及軸承蓋處均做了強(qiáng)化處理。至于缸蓋則采用了全新的硅鋁合金材料，確保了一流的強(qiáng)度和高溫性能。在活塞表面奧迪則采用了創(chuàng)新的涂層，使得內(nèi)部摩擦得到了進(jìn)一步的降低。
  在一系列創(chuàng)新工程的基礎(chǔ)之上，這款全新的發(fā)動機(jī)自重僅148kg，比上一代足足減少了5kg，使得這款全新發(fā)動機(jī)在具備一流性能的基礎(chǔ)上還有一流的燃油效率和節(jié)油潛力。

The brand-new engine on the brand-new S3

The long-stroke 2.0 TFSI in the Audi S3 has been developed from scratch. The only thing it has in common with its predecessor, which was named Engine of the Year five times in a row between 2005 and 2009, is its displacement of 1,984 cc (bore x stroke 82.5 x 92.8 millimeters). The four-cylinder unit delivers a constant 380 Nm of torque to the crankshaft between 1,800 and 5,500 rpm. Rated power at 5,500 rpm is 221 kW , and the engine redlines at 6,800 rpm.

The S3 delivers impressive performance. The sprint from zero to 100 km/h is completed in 5.1 seconds when equipped with the S tronic (5.4 seconds with the manual transmission). The electronically governed top speed of 250 km/h (155.34 mph) is just a formality. The S3 with S tronic consumes on average just 6.9 liters of fuel per 100 km (manual: 7.0 liters). This corresponds to CO2 emissions 159 (162) grams per kilometer and for models equipped with the manual transmission, an improvement of 1.5 liters compared with the previous version.

The powerful four-cylinder engine features two balance shafts rotating at twice the speed of the crankshaft for tremendous smoothness. The sound is emotion-inspiring and sporty. An electromechanical sound actuator at the bulkhead brings the engine sound to life in the cabin. The exhaust system also includes a sound flap that opens at certain engine speed ranges to give the S3 a sportily sonorous sound.

The 2.0 TFSI boasts groundbreaking solutions in many fields of technology. One of these is the additional use of indirect injection. It supplements the FSI gasoline direct injection at part load to reduce consumption and particulate emissions. FSI injection, which works at pressures up to 200 bar, is used when starting and at higher loads.

The developers achieved new degrees of freedom when it comes to filling the combustion chambers. On the exhaust side, the Audi valvelift system varies the stroke of the valves in two stages; the camshaft on the intake side can be adjusted steplessly through 30 degrees of crankshaft angle while 60 degrees of adjustment is available on the exhaust side. The compression ratio of 9.3:1 is unusually high for a turbocharged engine.

The exhaust manifold is integrated into the cylinder head, where it is bathed in coolant. This solution lowers the temperature of the exhaust and accelerates warmup following a cold start, which lowers consumption during the cold-start phase. This concept also has a positive effect on fuel consumption during sporty driving because full-load enrichment is no longer necessary. The large turbocharger is also a new development. It achieves a maximum boost pressure of up to 1.2 bar for even more spontaneous engine response. A high-performance intercooler integrated into the water circuit greatly reduces the temperature of the compressed air and thus increases the amount of air required for combustion.

With the 2.0 TFSI’s innovative thermal management system, two rotary slide valves consolidated in a single module regulate the flow of coolant. These valves ensure that the engine oil heats up to its operating temperature soon after the vehicle is started; they also maintain the coolant temperature, as per a given driving situation, between 85 and 107 degrees Celsius (185.0° F and 224.6° F). As a result – regardless of load or engine speed – the valves always strike the perfect balance between minimal friction and high thermodynamic efficiency.

The 2.0 TFSI has been designed specifically for use in the new Audi S3. Pistons with stronger bolts and new rings plus reinforced connecting rods with new mounts transfer the power to the crankshaft. The gray cast iron crankcase has been reinforced at the main bearing seats and the main bearing cover.

The cylinder head is made of a new, particularly lightweight aluminum-silicon alloy characterized by high strength and temperature resistance.