New VW 122 PS TSI Engine In Detail

In addition to the current twincharged (turbo + supercharger) 170hp and 140hp TSI engines, this third engine is the newest addition to the TSI lineup. It retains the same 1.4 liter iron crankcase as the larger TSI engines, however, it is not twincharged since it loses the supercharger but keeps the turbo. Set to replace the current 1.6 FSI engine (85 kW / 115 hp), the new TSI engine at 122hp (90 kW) makes 200Nm of torque, 30% more than the 1.6 FSI, and reduces fuel consumption by 6 percent. Torque curve is impressive by achieving 80% maximum torque at 1250 rpm and then holding 100 percent torque from 1500 rpm to 3500 rpm. Full details in the press release below.

Press Release

Overview

TSI Engine Offensive

• New TSI with 122 PS: Economical and Powerful

• Economical: New TSI consumes six percent less fuel

• Powerful: Maximum torque of 200 Nm in reserve at a low 1,500 rpm

Maximum power with minimum fuel consumption - this characteristic has, within a very short period of time, made TSI four-cylinder engines a synonym for a new generation of economical and at the same time sporty Volkswagen engines. Performance specifications: 125 kW / 170 PS and 103 kW / 140 PS. The Golf, Golf Variant, Golf Plus, Jetta and Touran are powered by them. In 2006 and once again in 2007 they were awarded the coveted "Engine of the Year Award". Now Volkswagen is presenting the third TSI; this one is 90 kW / 122 PS strong and will be introduced to the Golf lineup this year.

The new TSI will replace the 1.6 FSI with 85 kW / 115 PS in the mid-term. Decisive advantages of the new turbo engine: Besides being able to reduce fuel consumption by about six percent, the engine's power and torque characteristics were also improved significantly. Due to its smaller displacement, vehicle taxes are also lower. Compared to the 1.6 FSI, maximum torque has now been increased by nearly 30 percent to 200 Newton-meter. And this power is already available at 1,500 rpm. In addition, 80 percent of the maximum torque is already available at speeds as low as 1,250 rpm. In the lower speed range the TSI even exhibits Newton-meter gains of up to 66 percent compared to its predecessor.

Another plus when it comes to economy: Since its maximum torque is available over a broad speed range from 1,500 to 3,500 rpm, conditions are ideal for combining the new TSI with longer and therefore fuel-saving gear ratios. That is why in the future Volkswagen is planning to pair it with the first transverse seven-speed dual clutch transmission in the world (DSG). Its debut will also be in 2007.

Key facts about the new engine at a glance:

• Utilized in models up to the Passat.
• 90 kW / 122 PS power between 5,000 and 6,400 rpm.
• 200 Nm maximum torque from 1,500 to 3,500 rpm.
• 80 percent of maximum torque starting at 1,250 rpm
• Maximum torque 30 percent greater than in the 1.6 FSI.
• 66 percent more torque at 1,500 rpm.
• Fuel consumption is about six percent lower.
• Specific torque of 144 Nm per liter.
• 16V in-line four cylinder of the EA111 engine series.
• 1,390 cm3 displacement.
• Cylinder spacing: 82 millimeters.
• Bore and stroke: 76.5 and 75.6 millimeters.
• Compression 10:1.
• Electronic gasoline direct injection.
• Electronic-map ignition with cylinder-selective anti-knock control.
• Advanced combustion process.
• New intake port without charge movement flaps.
• Turbocharger (max. 1.8 bar)
• 220,000 rpm as maximum rpm of the turbocharger.
• Electrically-controlled divert-air valve for turbocharger.
• Water-cooled charge air in intake port.
• Fuel: Super unleaded (95 ROZ).
• Reduced friction losses.
• Total engine weight per DIN: 131 kilograms.

 

TSI Offensive

TSI with 122 PS

• 122-PS TSI was created for models ranging up to the Passat

• Powerful: Maximum torque of 200 Nm in reserve at a low 1,500 rpm

• Economy: New TSI consumes six percent less fuel

Maximum power with minimum fuel consumption – this characteristic has, within a very short period of time, made Volkswagen TSIs a synonym for a new generation of economical and at the same time sporty engines. Performance specifications: 125 kW / 170 PS and 103 kW / 140 PS. The Golf, Golf Plus, Golf Variant, Jetta and Touran are powered by them. In 2006 and once again in 2007 they were awarded the coveted "Engine of the Year Award". Now Volkswagen is presenting the third TSI, this time 90 kW / 122 PS strong. It will be introduced on Golf and Co. later this year. The new TSI is also being built at the Volkswagen plant in Chemnitz.

The new turbo engine replaces the 1.6 FSI with 85 kW / 115 PS. Advantages of the new TSI: Compared to the 1.6 FSI, maximum torque has now been increased by nearly 30 percent to 200 Newton-meter (starting at 1,500 rpm). 80 percent of the maximum torque is already available at speeds as low as 1,250 rpm. In the lower speed range the TSI exhibits Newton-meter gains of up to 66 percent. Despite its decisively improved power and torque characteristics, it was possible to reduce fuel consumption by about six percent.

Operating principle

The new 90-kW TSI

Effective actions taken to reduce fuel consumption and improve driving dynamics are direct gasoline injection, engine charging and reduction of engine displacement. Volkswagen is taking precisely this approach in its TSI engines: Reducing engine displacement, and thereby lowering friction and throttle adjustment losses, results in lower specific fuel consumption and a higher level of efficiency. Depending on the performance class, this is done either by a combination of turbocharger and supercharger, or simply with a specially developed turbocharger as on the new TSI.

The TSI, which is 90 kW strong over a wide range from 5,000 to 6,400 rpm and offers a very high specific torque of 144 Newton-meter per liter, delivers exceptionally agile response even from very low engine speeds without the addition of a supercharger. There is no turbo hole here. When it comes to forming the charge mixture, Volkswagen implements, and this is the case in its TDI engines as well as the TSI, a combination of engine charging and direct injection. Here too it is clearly evident that gasoline direct injection and engine charging complement one another ideally and together enable an unprecedented increase in efficiency.

Engine

The basic layout

The 1.4-liter TSI is an in-line 16V four-cylinder engine of the new EA111 engine generation with 1,390 cm3 displacement, cylinder spacing of 82 millimeters, a bore/stroke ratio of 76.5 to 75.6 millimeters, electronic gasoline direct injection, electronic-mapped ignition with cylinder-selective anti-knock control, turbocharger and intercooling. The TSI exhibits 10:1 compression, which is relatively high for a turbocharged engine and is fueled with more economical super (95 ROZ) fuel. A new generation of pumps ensures optimal buildup of high pressure in the injection system.

A primary focus in the development of the third TSI was to reduce friction losses even further. Advanced development of the combustion process and a redesign of the intake port made it possible to do without charge movement flaps in the intake port. Simultaneously, an absolute requirement set forth in the specification was that the car must be able to achieve a level of agility similar to that of the twincharged TSI engines. And that was not all that was required: The TSI also had to be able to serve as a mass-produced engine for model series ranging up to the Passat.

The 90-kW engine shares the following components with its two stronger brothers:

• Gray cast iron cylinder crankcase in open deck construction (ensures optimal cooling in the upper cylinder area).
• Timing case that integrates the oil filler, crankcase venting and oil filter module.
• Valves are driven by a robust and practical, hydraulically-tensioned toothed chain.
• Steel crankshaft.
• Connecting rod.

TSI weight savings

The hunt for every gram

The 140 PS and 170 PS TSI engines are already lightweight. Yet, standing still is really a step backwards. So consistent efforts were made to reduce the weight of the new TSI even more. Its pistons and valve reliefs were designed as lightweight castings, and the geometries of the asymmetrical stem and wall thicknesses were also optimized to handle their loads. That is how weight was trimmed gram for gram. On the cylinder head, whose fundamental concept is also based on the stronger TSIs, it was possible to reduce weight by about 600 grams with a structure-optimized design.

The Volkswagen engineers also reconfigured the intake port. Based on the large TSI, it was further developed with the goal of achieving a level of swirl or tumble that would not require charge movement flaps, as already mentioned. In addition, the new intake port was substantially modified. The advantage: Over broad sections of the engine's operating range, it was possible to achieve quicker and even more efficient combustion with better fuel economy and a smoother engine characteristic.

Valves on the TSI are actuated by two camshafts, also further optimized, with inlet-side adjustment. Various modifications enabled weight savings here too: The camshafts each weigh 304 grams less. Every gram counts. That is why even the cylinder head cover is 150 grams lighter. Overall, the 90-kW TSI is 14,000 grams or 14 kilograms lighter than a TSI with 125 kW.

TSI Turbocharger

And intercooling

The turbochargers are compact and therefore weight-optimized in design too. In keeping with the overall concept, the best dynamics and lowest fuel consumption were top priorities. The very quickly responding turbocharger and very narrow intake and exhaust cams together with intake camshaft adjuster, are also responsible for making 80 percent of the 200 Newton-meter maximum torque available at a low 1,250 rpm. The refined flow optimization of the integral exhaust manifold and a very carefully optimized exhaust turbine also deliver excellent, low-loss engine charger operation, even at high speeds. The maximum speed of the turbocharger is 220,000 rpm.

Integrated directly in the charger’s compressor housing is the electrically-controlled divert-air valve. Its advantage compared to a pneumatic valve: Its construction is more compact and less complex. In addition, it produces significantly shorter switching response times, so that the turbocharger always operates optimally, even with abrupt throttle adjustments. An electrically-controlled divert-air valve was introduced for the first time on the turbo engine of the current Golf GTI.

An innovation on the new TSI is its water-flow intercooler, which is positioned right in the intake port. It is part of a low-temperature circulation loop that is independent of engine cooling. The advantage here: The charge air system exhibits a lower volume than in conventional approaches that utilize a front intercooler. Numerically speaking, it was possible to reduce the volume from about 11.0 to 4.8 liters. This significantly shortens the time required to reach a charge pressure of 1,700 millibar in the intake port. The results: Improved dynamics due to minimal delays in filling the combustion chamber to its maximum. And the driver of a Volkswagen equipped with the 122-PS TSI can experience this dynamic gain.

Injection

Modified injection technology

Electronic direct injection is marked by a newly developed high-pressure injection valve with six fuel spray holes. Background: A multi-hole high-pressure injection valve of this type was first used on the "large" TSI engines. However, on the "small" TSI the spray behavior was significantly modified. The fuel mixture is distributed more efficiently in the combustion chamber thanks to a new design of the six injection jets that are adapted to the specific needs of this engine. This enabled ignition timing adjustment, and one result of this was significantly lower HC emissions (hydrocarbons). The injector itself is arranged on the intake side between the intake port and the cylinder head gasket level; the maximum injection pressure is 110 bar.

The TSI family

• TSI stands for maximum power and minimum consumption

• TSI engines from Volkswagen revolutionize the world of gasoline engines

• The only volume production engines in the world with turbocharger plus supercharger

The first car in the world to have TSI on board was the Golf GT. The 125 kW / 170 PS power and 240 Newton-meters of torque on this "small brother" of the Golf GTI contrast with a low 7.2 liters per 100 kilometers average fuel consumption. This sporty Golf races to the 100 km/h mark from a standstill in just 7.9 seconds. And at 220 km/h it has reached its top speed. Standard equipment on the Golf GT includes a six-speed transmission, but the technically unique DSG dual clutch transmission is available as an option on this Volkswagen too. Meanwhile, the "large" TSIs paired with DSG are not just reserved for the Golf; the engine and transmission are available today on the Golf Plus, Golf Variant, Jetta and Touran too.

Representing the technical foundation of the TSI –on the new, "small" TSI with 90 kW, for example – is a 1,390 cm3 displacement four-cylinder engine, whose dynamics, in the case of the GT, match those of a 2.5-liter naturally aspirated engine. The TSI already develops its maximum torque at 1,750 rpm, which is then constantly in reserve up to 4,500 rpm.

The second TSI is the engine version debuting in 2006 on the Golf, Jetta and Touran with 103 kW / 140 PS. TSI stands for a new type of downsizing: For less displacement, less fuel consumption, lower emissions, yet more power, more torque and more driving fun. The 140-PS TSI develops 220 Newton-meter torque at a low 1,500 rpm and holds this value constant up to 4,000 rpm. To ensure that driving fun is not spoiled when refueling at the pump, all TSI engines are designed to operate with economical, super 95 ROZ fuel.

Supercharger boosts pressure at low end

To increase torque at low engine speeds, engine developers selected a supercharger that is mechanically-driven by a belt. This charger is based on the Roots principle. A special feature of the supercharger being used is its internal gearing stage located in front of the synchronization gear pair, which enables high supercharger boost performance at low engine speeds.

Turbocharger kicks in at the upper end

At higher engine speeds the turbocharger (with wastegate control) kicks in. The supercharger and turbocharger are arranged in series here. The supercharger is actuated by a magnetic clutch integrated in a module within the water pump. A control flap ensures that the necessary fresh air is supplied to the turbocharger or supercharger for the given operating point. In pure turbocharger operation the control flap is open. The air then takes the route of conventional turbo engines, via the front intercooler and throttle valve and into the intake port.

The maximum charge pressure of the twincharger is approx. 2.5 bar at 1,500 rpm. Only in the lower speed range below 2,400 rpm is the supercharger needed to generate the necessary charge pressure. The turbocharger is designed for optimal efficiency in the upper performance range, and it also supplies sufficient charge pressure in the middle speed range.