Fiat engine technology is coming to the US. It's the concept of "downshifting", achieving the power of a larger engine with a much smaller unit. We've seen this concept of turbocharging a smaller engine to achieve the horsepower of the larger engine before. What is new is the application of MultiAir, the technology that Fiat invented, that boosts torque output, fuel economy, drivability all while lowering emissions.
Previously, these smaller turbocharged engines would make good power when on boost, but suffer from a lack of torque at lower rpm and when off boost, taking away from their drivability and driver enjoyment. MultiAir (which has been described as variable valve timing on steroids) boosts torque and drivability during these periods and truly enable the smaller engine to better match the larger engines drivability.
With the TwinAir, Fiat has taken this concept to the extreme. The TwinAir is a twin cylinder 85 hp, 875cc engine that puts out 25% more horsepower than the 69hp, 1.2 liter 4 cylinder engine that is standard in the European Fiat 500. But what is even more impressive is that the TwinAir matches the performance of the 100hp, 1.4 liter 16v engine and even outproduces the larger engines torque at 2000rpm.
And that's not all, there will be a 105hp version of the TwinAir that really promises to turn the world upside down in terms of what is thought of engines with less than four cylinders.
Will the TwinAir come to the US? Well, that awaits to be seen, but we will see MultiAir and the downshifting technology applied to Chrysler products.
You can read my previous posts on the TwinAir here and below is the official Fiat Press release describing the TwinAir:
A memorable event was organized in Turin, on 4 July 2007 to introduce the new Fiat 500, exactly 50 years after the original Fiat 500. From that day, the second generation of the model that epitomized the history of Italian cars, was quick to win everyone's hearts. For the many enthusiasts and customers worldwide, Fiat decided to celebrate each birthday of the pocket-sized 500 with special events and by introducing a new product bound to appeal to all.
In 2008, for example, picnics were organized in the main European capitals and the mighty Abarth 500 was introduced. The same thing happened in 2009 for the international presentation of the Fiat 500C, the original cabriolet version intended as a homage to the style of the 1957 open-topped car, which has already notched up more than 34,000 orders. In July, to celebrate the car's third year in existence, Fiat chose to launch its 85 HP (875 cc) TwinAir twin-cylinder engine on the 500 model, both saloon and cabrio..
The 500 is the first Fiat model to adopt this forerunner of a new family of engines: an 85 HP (875 cc) turbo two-cylinder with the lowest CO2 emission levels in the world for a petrol engine (92 g/km with a Dualogic robotized gearbox and 95 g/km with manual gearbox). All this is achieved without detracting from performance and driving satisfaction.
This is thanks to the small-sized turbine which, combined with dedicated valve management strategies, minimizes transient response times and, at the same time, keeps maximum power levels high. In this way, despite its small size, the engine ensures excellent performance and an appreciable reduction in fuel consumption: compared with a 1.2 8v, the 85 HP TwinAir records a power increase of 25% together with a 15% reduction in fuel consumption. In fact, the performance of the twin-cylinder unit is not only equivalent to a 1.4 16v, but its fuel consumption is a remarkable 30% less.
A Fiat 500 powered by a TwinAir engine can reach a top speed of 173 km/h and accelerate from 0 to 100 km/h in only 11 seconds. This remarkable performance corresponds to a significant reduction in fuel consumption: 4.0 l/100 km and 4.1 l/100 km with a Dualogic robotized gearbox and manual gearbox respectively. The Fiat 500 with an 85 HP TwinAir also comes with an ECO button – positioned on the dashboard – to cut fuel consumption still further around town and guarantee a genuinely eco-friendly drive by offering driving modes: Normal and ECO.
In the first mode, the ECO function is off and the engine delivers the maximum available torque (145 Nm), guaranteeing verve and a prompt response for a sportier drive. Steering power-assistance is also specifically calibrated for Normal mode. No indication appears on the dashboard in this mode (City is not selected). This configuration is therefore recommended for maximum response and full appreciation of all the available torque.
In ECO mode, on the other hand, the emphasis is on an eco-friendly drive: torque delivery is cut to 100 Nm at 2000 rpm to minimize fuel consumption and promote a driving style more suitable for town traffic. The effort required at the steering wheel is also lighter (CITY mode is automatically selected). The driver only needs to press the specific button on the dashboard to activate the ECO function. The lettering ECO will appear on the panel (the letter “E” will appear on the panel if the car has a Dualogic robotized gearbox). The Dualogic shifting strategy also switches to ECO mode to further optimize fuel consumption when a Dualogic gearbox is fitted.
Compared to a medium-sized four-cylinder unit of equal performance, the new engine is also significantly shorter (-23%) and lighter (-10%), opening the way to further developments, such as methane fuel system or hybrid technology combinations, again with a view to greater eco-friendliness. In particular, a methane version of the TwinAir will soon be available, guaranteeing a further CO2 emission reduction by adopting a pair of special injectors in addition to the petrol injectors on the intake manifold port.
Improving on these fuel saving results using internal combustion engines will be difficult and alternative technologies will need to be developed. The combination of traditional engines and electric motors appears particularly promising. Due to its reduced size, the TwinAir is most suitable for pairing with an electric engine and in general with any device located between the engine and gearbox designed to recover and store the energy that is normally dissipated during braking.
The 85 HP TwinAir unit also comes with Start&Stop as standard. This device temporarily stops the engine and restarts it, ensuring reductions in fuel consumption and noise in the passenger compartment when the device is in operation. The Gear Shift Indicator (GSI) fitted in conjunction with the Start&Stop is a veritable co-pilot that discreetly suggests to drivers when they should change gear, leading to more efficient use of the power unit in terms of fuel consumption. For example, the GSI may suggest shifting up, by means of an indication on the control panel, to allow the engine to burn a leaner mixture, i.e. one containing less fuel, or shifting down to make best use of the available torque.
Nothing short of an engineering gem, the twin-cylinder unit implements the revolutionary MultiAir technology developed and patented by FPT – Fiat Powertrain Technologies, which was first introduced on FIRE power units last year. The heart of MultiAir is a new electro-hydraulic valve management system that reduces fuel consumption by controlling air directly via the inlet valves (without using the throttle).
MultiAir reduces polluting emissions (thanks to combustion control) and also considerably improves performance and drivability with respect to a traditional petrol engine of equal displacement.
In brief, the advantages of MultiAir technology applied to petrol engines are:
- maximum power boosted by 10% with respect to a traditional engine of equal size;
- 15% more torque at low rpm and during transitions by applying early intake valve closing strategies to maximize the air introduced into the cylinders;
- less fuel consumption and consequently lower CO2 emissions, equal to 10% by eliminating pumping losses and precise parameter calibration for optimizing combustion;
- lower polluting emissions from the engine by optimizing valve control strategies during the intake stage;
- a more prompt response to accelerator commands due to the constant air pressure upstream of the cylinders combined with extremely fast control of the intake valves.
The new TwinAir engine also takes the concept of downsizing to an extreme: by combining a small-sized engine with a next-generation turbocharger, performance comparable to – or even better than – that of a larger engine is obtained, but with less fuel consumption and lower emissions.
Not only that, the turbo significantly increases maximum torque, making it available at a very low rpm, with the result of offering greater flexibility and an unrivaled responsiveness compared to conventional aspirated engines. All this comes with a relatively simple build to the benefit of strength and reliability.
Last but not least, the new engine was painstakingly optimized and tuned. For instance, the basic twin-cylinder architecture - combined with the low friction of internal parts - makes this engine best-in-class at a world level in terms of low friction. Furthermore, calculated simulations have been used to identify the best possible unit displacement in terms of thermo-dynamic efficiency, and the best fluid dynamic configuration to optimize and get the best out of the MultiAir system.
Finally, special attention has been placed on the NVH (Noise, vibration, and harshness) aspect to ensure vibration performance at least equivalent to that of a four-cylinder, with equal performance but with a characteristic sound. For this purpose, a balancing counter-shaft was used to maintain optimal vibration levels in all operating conditions of the engine, from idling speed to maximum power.
The Fiat 500 range also offers eco:Drive, innovative software for analyzing driving behavior and helping motorists optimize consumption and emissions by using the USB port of the Blue&Me system.
Finally, Blue&Me – TomTom, the latest evolution of the Blue&Me system, will be appearing on the Fiat 500 along with the new TwinAir engine. This is a fully integrated infotainment system that allows you to manage telephone, navigation and useful driving information functions through the Tom Tom's color touch screen interface. The application of this system on the Fiat 500 will also enable additional functionality that will also allow the media-player to be managed through the touch screen interface. The Blue&Me – TomTom is located in a dedicated housing on the dashboard that combines the safety, convenience and practicality of an integrated solution with the flexibility of portable devices. The device is constantly charged through the dedicated housing and may be controlled by means of steering wheel controls and also the touchscreen interface.
The device is the result of a partnership between Fiat Group Automobiles and TomTom, the European leader in portable navigation systems, and integrates with the car’s other systems via the Blue&Me system developed in collaboration with Magneti Marelli.
Fiat TwinAir Website
With thanks to Fiat Group Press, Chrysler Media