Um... Chris explain this to me.

VW Develops Turbocharged and Supercharged Engine for Mass Consumption
Since When Could Any 1.4-Liter Engine Make 170-Horsepower?

First, there was TDI, Volkswagens version of turbo diesel injection. Over the decades it has become what might now be the worlds best-known diesel engine lineup, a trademark name for some of the worlds most advanced and most powerful diesel engines.

Then, not four years ago, VW introduced another three-letter acronym, FSI, which stands for Fuel Stratification Injection, VAGs version of direct-gasoline injection. The technology that fuels common-rail turbodiesel engines has been adapted for gasoline use, injecting a fine mist of gasoline directly into the combustion chamber to promote better combustion. Compared to traditional fuel injection, FSI engines generally make 10 percent more power, while using 10 percent less fuel. FSI technology proved itself in the 24 Hours of Le Mans, helping Audis R8R racers take 1st, 2nd and 3rd place sweeps three years in a row.

And now for something completely different… TSI. The worlds first “Twincharger” enhanced engine. A powerplant thats both turbocharged and supercharged!

It has long been thought that when considering forced aspiration, a motor could have either a turbocharger or a supercharger. Turbochargers are often used to get maximum potential out of small displacement engines. Theyre also relatively inexpensive, especially if compared to the cost of developing an all-new naturally aspirated engine with similar performance. However, as they rely on the engines exhaust gasses to produce boost, turbochargers often succumb to lag, the annoying pause felt while waiting for the turbo to spool up to optimum boost. While this has since been solved by low pressure turbos or twin-turbos that couple a small, low-boost, lag-free turbo to get the motor up to speed before switching over to a large, high-boost turbo for maximum power.

The other option is a supercharger, a belt-driven blower that provides most of its boost near idle, but is limited in maximum operation speed by heat and friction. There have been a few attempts to mate the two together, specifically Ferrari-tuner Koenig, and its super-tuned Testarossa, but never has such a system achieved mass production.

vehicles aVWs goal with the TSI engine was not to create the ultimate performance engine, for use in the top-line Passat, pricey Touareg or premium Phaeton, but to provide a high-power, relatively low-cost motor without large displacement. With the implementation of European emission controls, wherere taxed on the basis of the amount of carbon dioxide released per mile (or kilometer) driven, it was clear to officials that this reasonably sporty machine must also be affordable to run and purchase. Volkswagen chose the 90-horsepower 1.4-liter FSI engine from the EA111 series as the base for this new engine, the smallest of its FSI powerplants.

The German brands preparation for the Twincharger system included increasing displacement of the engine by 10 cc to 1400 cc even, a more powerful fuel rail capable of delivering gasoline at 2,175 psi of pressure, increasing the compression ratio to 10.0:1, and fitting the engine with an extra-resilient cast-iron crankshaft capable of enduring the engines high pressure for extended periods of time.



And now the complex part: explaining how VWs system works. Adapting the FSI engine for turbocharging wasnt a difficult task for VWs engineers, as a turbo was already fitted to the 2.0 FSI motor to produce the 2.0 FSI-T found in the VW GTI/Jetta GLI/A3 Sportback, etc. The challenging issue was how to get the supercharger to work together with the turbo. In the TSI engine, the two blowers are mounted in sequence with a control valve that allows them to operate together or individually. The supercharger, of course, is the new and slightly unusual component. It is a belt-driven “Roots” type blower, however, unlike regular superchargers that are constantly in use, its belts are operated by a magnetic clutch found inside the water pump that is overseen by the automatic boost pressure control system. The system is designed to enable the supercharger to produce boost at lower rpm, and switching over to the turbo at higher revs.

Together, the supercharger and turbocharger create a power source thats not only extremely potent due to its high boost, but one thats incredibly responsive as well. At just above idle, the supercharger produces 26 psi of boost - more than most turbocharged vehicles are producing at maximum boost! VW claims that power is always on tap, with a minimum of 148 lb-ft of torque available to the driver between just 1,250 rpm and 6000 rpm. The automatic boost pressure control system is responsible for deciding when the switchover from supercharger to turbocharger should take place, and observes engine rpm, and which gear the vehicle is in. With the supercharger providing boost and keeping the engine spinning fast enough, the usual switchover to turbo occurs before 3,500 rpm, a speed where the turbo is capable of sustaining maximum acceleration without any pause or delay.

When working together at a boost ratio of approximately 1.53, the two forced aspiration units create a total boost of about 36.3 psi at 1500 rpm, an astonishing figure considering there is no turbo lag whatsoever. Equally amazing is the total output; the two forced aspirators give the 1.4-liter engine a total of 170 horses, making for an unparalleled specific output of 121-horsepower per liter. VW rates the tiny 1.4-liter engine comparable to that of a naturally aspirated 2.3-liter unit - 177 lb-ft between 1750 - 4500 rpm. If this wasnt a sweet enough deal, fuel consumption is 20 percent less, using just 39.2 mpg in the city and 47.9 mpg on the highway. Carbon dioxide (CO2) emissions, the reduction of which was a critical element of the program, are just 140 g/km. Later in 2006, Volkswagen will introduce a less powerful version of this motor with 140-horsepower and 162 lb-ft of torque for global (non-North American) market Golfs, Jettas and Tourans (VWs Euro minivan).

However amazing this new powerplant is with its high output, efficient consumption and minimal emissions, Volkswagen needs to overcome the black-mark left by the 1.8T engine. Offering such technologies as light-pressure turbocharging and five valves per cylinder, it wowed the globe at first for its responsiveness and performance, but left many a customer vexed with its less than palatable reliability. Volkswagen wants to rebuild its image, selecting high-quality materials that are able to withstand the high pressures and 7,000 rpm redline of the new turbo and the supercharged motor. More than 250 prototypes were created and put through the standard tests including endurance runs of over 186,420 miles. So far, the base EA111 motor has been in production for four years, and has not run into any significant quality issues. Fingers are crossed for the new engine.

The new TSI will make its world debut in the upcoming Golf GT during this years Frankfurt motor show. With 170-horsepower, it bridges the gap between the regular 150-horsepower 2.0 FSI motor and the higher performance 200-horsepower 2.0 FSI-T vehicle. Available transmissions include the 6-speed manual gearbox, or 6-speed DSG twin-clutch unit.

Volkswagen hasnt made any mention about offering the 1.4-liter TSI motor to the North American market, but with the upcoming U.S. Tier II emissions controls and the rapidly rising price of gasoline, the automaker may consider it for an upcoming compact model. And if youre interested in that previously mentioned Golf GT model, stay tuned for a preview later this week.

http://www.automobile.com/vw-develops-turbocharged-and-supercharged-engine-for-mass-consumption.html

 

A 4 banger can make alot more than 170HP...

Using both types of forced induction makes sense....supercharged for low end- non lagging input...and turbo charged for high end input with a spooled up engine....Kind of a best of both worlds thing.



PS- Did I mention...I WANTS....

 

Yea it's pretty cool. Although turbos have come along way and lag isn't as much of an issue anymore.

 

As much...but it's still there...Mechanically it HAS to be there...even if it is miniscule...

 

Well thats why alot of carmakers (BMW comes to mind) is using a twin-turbo set up. Basically a big one and a small one. The small turbo engages quicker than the bigger turbo which cuts down on the lag considerably.

 

Also true. I almost bought a twin turbo supra when I was in college...Now I'm glad I didn't...cause I wouldn't be posting here...I'd probably be dead.

 

I believe they're using TurboSupercharger in place of just plain turbo in that Allison V1710 article.