Drives: fat cars are still boats
Join Date: Jun 2007
Location: compensating a fat car with horsepower is like giving an alcoholic cocaine to sober him up.
If Audi believes in compressor supercharging why wouldn't it be also feasible in this Toyobaru?
SOURCE Audi of America, Inc.
HERNDON, Va., Dec. 15, 2011 /PRNewswire/ -- Audi today announced that the Audi 3.0 L TFSIŽ supercharged V-6 engine has secured a position on Ward's 10 Best Engine list for 2012. Now in its 18th year, Ward's 10 Best Engines recognizes the latest powertrain technologies that are affordable to most consumers, boost horsepower and torque, sound appealing and integrate well with their respective vehicles.
For the 2012 Ward's 10 Best Engine awards, editors tested 36 vehicles and scored each engine based on power, technology, observed fuel economy and noise, vibration and harshness characteristics. Each engine was required to be available in a regular-production U.S.-specification model on sale no later than first-quarter 2012, in a vehicle with a base price below $55,000.
"With so many engines featuring gasoline direct-injection and forced induction, we're pleased to have a list that is rich in technology," says Drew Winter, editor-in-chief of WardsAuto World. "Plus, every engine reinforces the idea that even fuel-efficient vehicles must be fun to drive."
For 2012, Audi's 3.0 L TFSI supercharged V-6 engine returns to Ward's 10 Best Engine list for a third consecutive win. With 310 horsepower and 325 lb.-ft. of torque, the all-aluminum engine is unapologetically powerful. With peak torque available from 2,900 to 4,500 rpm, power is available at any speed. And, the four vane Roots-style supercharger helps this motor achieve V8 power and torque with the efficiency of a V6.
The Audi 3.0 L TFSI supercharged V-6 engine not only powers the new 2012 A6 sedan, but also powers the new 2012 Audi A7 5-door coupe, the Audi Q7 full-size luxury sport-utility vehicle, as well as the S4 sedan and the S5 luxury coupe.
For 2013, the Audi S5 Coupé will finally have its long awaited move to the 3.0L Supercharged V6 TFSI power plant producing 333 hp, an engine already used in the S5 Cabriolet and S4 Sedan/Avant since the 2010 model year. The other major change under the bonnet is the introduction of stop-start technology for better fuel efficiency. Audi claims an average fuel economy of 8.9 litres/100 km (compared to the current 12.6 litres/100 km in the V8 coupe and 10.7 litres/100 km in the Cabriolet).
American OEM firm Eaton Corporation has announced that its Twin Vortices Series (TVS) supercharger has been chosen by Audi for its new 3.0 liter TFSI V6 engine. The new engine will go into production later this year and will be used for a range of Audi models including the new S4 and possibly even the next RS4. Initial applications will see the forced-fed engine produce a peak output of 290hp (213kW) and 310lb-ft (420Nm).
While many of its rivals have adopted turbochargers in their quest to boost performance without significantly increasing fuel-consumption, Audi decided to go the supercharging route because of the extra available power at lower revs than a comparable turbocharged mill.
The compressor is so compact that it easily fits inside the 90-degree V of the cylinder banks, in place of the intake manifold. Because it’s driven by the engine via a poly-V belt, its full thrust is available from idle speed upwards, producing huge pulling power when driving off. The gas paths after the compressor are also very short, which means that torque is built up extremely quickly.
“Audi engineers did extensive comparative testing and found our new TVS supercharger provided superior throttle response and low-end torque coveted by drivers," explained Eaton's powertrain chief Joao Faria.
The Eaton TVS is an all-new Roots-type positive displacement supercharger that features twin four-lobe rotors that are twisted 160-degrees. The intermeshing, high-speed rotor design pumps air directly into the engines intake system and is more efficient than previous designs. The rotors can deliver 1,000 kilograms (2204.62 lb) of air per hour and force it into the combustion chambers at a boost pressure of up to 0.8bar.
By comparison, the original Eaton supercharger features three lobes twisted at 60 degrees. The fourth lobe and added twist, when combined with redesigned air inlet and outlet ports, creates a smooth, highly efficient flow of air into the engine and has improved noise and vibration characteristics.
2008 PRESS RELEASE:
The new 3.0 TFSI: High-tech V6 with compressor supercharging
* Compressor and direct injection – a compelling duo
* 213 kW (290 hp), 420 Nm and outstanding efficiency
* Superb power from idle speeds up, spontaneous torque buildup
Powerful, spontaneous and ultra-efficient: this is the new top version in Audi's V6 engine range. The 3.0 TFSI develops 213 kW (290 hp) and a huge 420 Nm (309.78 lb-ft) of torque. It combines two state-of-the-art technologies in perfect style – gasoline direct injection and compressor supercharging. The hi-tech V6 will go into production later in the year.
The brand with the four rings has a long tradition of supercharged engines. The legendary Grand Prix racing cars built by Auto Union back in the 1930s already featured compressors, which coaxed as much as 440 kW (around 600 hp) out of the mighty 16-cylinder and 12-cylinder engines. From the late 1970s on, Audi focused its attention on the exhaust turbocharger, which helped it to a succession of noteworthy triumphs in the world of motor sport. It was at this time that Audi's turbo engines began to enjoy resounding market success.
The compressor is now staging a comeback. It is the ideal supercharging technology for the new three-liter V6, the 3.0 TFSI; the T in Audi engine designations consequently no longer exclusively denotes turbo versions.
Extensive comparative tests revealed the mechanical supercharger to be superior to a biturbo concept for this engine. In conjunction with direct injection, its packaging, starting performance and dynamic response were far superior.
The compressor is so compact that it easily fits inside the 90-degree V of the cylinder banks, in place of the intake manifold. Because it is driven by the engine via poly-V belt, its full thrust is available from idle speed upwards, producing huge pulling power when driving off. The 3.0 TFSI delivers its maximum 420 Nm (309.78 lb-ft) at only 2,500 rpm and maintains this constantly until 4,850 rpm.
The gas paths after the compressor are very short; this means that the torque is built up extremely quickly, even more dynamically than on a naturally aspirated engine of the same displacement. The 3.0 TFSI responds sportily to the throttle, with exceptional agility and bite. And it revs up to the maximum of 6,500 rpm with playful ease, achieving its rated output of 213 kW (290 hp) at just under 5,000 rpm.
Top marks for fuel efficiency
The 3.0 TFSI without question earns top marks for fuel efficiency, too. And its pulling power enables it to extend the transmission ratio, further adding to its already superior efficiency. The new 3.0 TFSI will achieve an average fuel consumption of well under 10 liters per 100 km (23.52 US mpg) in virtually all longitudinally engined Audi models, the concept for which it is envisaged. It is designed to run on either premium or regular gasoline and already complies with the future emission standard Euro 5 – a question of honor for every new Audi engine.
The Audi technology of gasoline direct injection according to the FSI principle was what made this trailblazing efficiency possible in the first place. Unlike conventional concepts, it allows the compressor to be located behind the throttle valve. In view of the low density of the intake air at loads below supercharging level and when coasting, its rotors are free-running and the amount of power required to drive them is low.
The engine's high compression ratio of 10.5:1 also plays a big part in its efficiency. The direct injection principle is once again the key, because the intensively swirled fuel cools the combustion chamber, reducing the tendency to knock.
The compressor of the new 3.0 TFSI is what is known as a Roots blower. Inside it, two four-vane rotary pistons counter-rotate at a speed of up to 23,000 rpm, with an air gap between them measuring just a few thousandths of a millimeter. The rotors can deliver 1,000 kilograms (2204.62 lb) of air per hour and force it into the combustion chambers at a boost pressure of up to 0.8 bar.
Two water-to-air intercoolers made from aluminum and connected to a separate coolant circuit are integrated into the housing. Here, the compressed and therefore heated intake air is cooled down again in order to boost its oxygen content for the combustion process. An extensive package of measures reduces the level of noise generated by the compressor to a minimum.
The engine itself belongs to Audi's family of ultramodern V engines. In addition to the standard cylinder angle of 90 degrees, their attributes include systematic lightweight construction – the three-liter version's crankcase, which is made from cast aluminum/silicon, tips the scales at just 33 kilograms (72.75 lb). The entire engine, including the compressor, weighs 189 kilograms (416.67 lb). The bore measures 84.5 millimeters (3.33 in) and the stroke 89.0 millimeters (3.5 in), producing a swept volume of 2,995 cm3.
Reinforcements on the crankcase
Audi has included a whole array of refined hi-tech features on the 3.0 TFSI. The crankcase has been adapted to the higher prevailing pressures and all components are frictionally optimized. The two intake camshafts can be adjusted through 42 degrees crankshaft angle. In the intake ports, tumble flaps induce movement in the incoming air to promote optimum mixture preparation.
The injection system is a fundamentally new design. A common rail system with six-hole injectors injects the fuel directly into the combustion chambers at a pressure of up to 150 bar. The injectors' highly dynamic response permits up to three fuel injections per operating cycle across an extensive range of the characteristic map. They, too, optimize the combustion process and therefore contribute to the impressive performance of the new 3.0 TFSI.