I always find it so interesting that when the Press says gas will go up it does. Now in the Press is the new legislation in the works that will force Manufacturers to up the MPG of vehicles and Wahla! But just like they always say it's just a strange coincidence.


DETROIT-- Ford Motor Co. plans to boost fuel economy by rolling out what it calls "twin-force" technology: Two turbochargers on four-cylinder V-6 and V-8 gasoline engines.

Derrick Kuzak, group vice president for global product development, said the technology will deliver diesel-like fuel economy. Diesels offer a 25 to 30 percent gain in fuel economy compared with gasoline engines of the same size.

The first vehicle to use the twin-force technology is the upcoming Lincoln MKS flagship sedan due in 2008. Twin-force engines also will use gasoline direct injection, which increases power, Kuzak said at a press event here.

He said Ford also plans what it calls its power shift transmission, a six-speed automatic that combines features of a manual with an automatic, and variable displacement V-8 engines

Sure makes you wonder. Why does a World Class Organization need to have pending legislation to induce it to introduce new technology that would be able to increase fuel economy?

I would think, that if this is as good as they say it is, I'd have introduced it and be Hyping to the world!!

Time will tell.

Red

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2005 Titan KC SE, Helwig, True-Track, ARE MX Canopy

It's just a coincidence...........riiiiight. But I am wondering how the twin turbo set up will do for endurance. Turbos require religious maintenance......... As you say, "Time will tell".

The term supercharging technically refers to any pump that forces air into an engine - but in common usage, it refers to pumps that are driven directly by the engine as opposed to turbochargers that are driven by the pressure of the exhaust gases.

Positive displacement superchargers may absorb as much as a third of the total crankshaft power of the engine, and in many applications are less efficient than turbochargers. In applications where engine response and power is more important than any other consideration, such as top-fuel dragsters and vehicles used in tractor pulling competitions, positive displacement superchargers are extremely common. Superchargers are generally the reason why tuned engines have a distinct high-pitched whine upon acceleration.

A supercharger (also known as a blower) is an air compressor used to force more air (and hence more oxygen) into the combustion chamber(s) of an internal combustion engine than can be achieved at ambient atmospheric pressure.

The additional mass of oxygen-containing air that is forced into the engine improves on its volumetric efficiency which allows it to burn more fuel in a given cycle - which in turn makes it produce more power. A supercharger can be powered mechanically by belt, gear, or chain-drive from the engine's crankshaft. It can also be driven by a gas turbine powered by the exhaust gases from the engine. Turbine-driven superchargers are correctly referred to as turbo-superchargers - or more commonly as turbochargers.

A turbocharger (short for turbo-supercharger) is an exhaust gas driven forced induction device used in internal combustion engines to improve engine performance by forcing compressed air into the combustion chambers, allowing more fuel to be burned, resulting in a larger power output.

A lag is sometimes felt by the driver of a turbocharged vehicle as a delay between pushing on the accelerator pedal and feeling the turbo kick-in. This is symptomatic of the time taken for the exhaust system driving the turbine to come to high pressure and for the turbine rotor to overcome its rotational inertia and reach the speed necessary to supply boost pressure. The directly-driven compressor in a supercharger does not suffer this problem. (Centrifugal superchargers do not build boost at low RPMs like a positive displacement supercharger will). Conversely on light loads or at low RPM a turbocharger supplies less boost and the engine is more efficient than a supercharged engine. Turbo-lag is often confused with the term Turbo-spool. Turbo Lag refers to how long it takes to spool the turbo when there is sufficient engine speed to create boost. This is greatly affected by the specifications of the turbocharger. If the turbocharger is too large for the powerband that is desired, needless time will be wasted trying to spool the turbocharger.

Turbodiesels are generally considered more flexible for automotive uses than naturally-aspirated diesels, which have strong low-speed torque outputs but lack power at higher speeds. Turbodiesels can be designed to have a more acceptable spread of both power and torque over their speed range or, if being built for commercial use, can be designed to improve either torque or power at a given speed depending on the exact use.

Turbochargers are in many ways more suited to operation in diesel engines. The smaller speed range that Diesel engines work in (between 1000 and 5000 rpm for a private car, and as little as 1000-2500 rpm for a larger unit in a commercial vehicle) mean that the turbocharger has to change speed less, reducing turbo lag and improving efficiency. Diesel engines do not require dump valves and have lower exhaust temperatures which reduces stress on the turbine blades. The turbodiesel engine can also help with the amount of torque it can give out. Commonly used in trucks, it helps improve the towing capacity of a truck, as well as fuel economy.

Turbo charged engines operating at wide open throttle and high rpm require a large volume of air to flow between the turbo and the inlet of the engine. When the throttle is closed compressed air will flow to the throttle valve without an exit (i.e. the air has nowhere to go).

This causes a surge which can raise the pressure of the air to a level which can be destructive to the engine e.g. damage may occur to the throttle plate, induction pipes may burst. The surge will also decompress back across the turbo, as this is the only path with the air can take.

The reverse flow back across the turbo acts on the compressor wheel and causes the turbine shaft to reduce in speed quicker than it would naturally. When the throttle is opened again, the turbo will have to spin-up for longer to the required speed, as turbo speed is proportional to boost/volume flow. In order to prevent this happening, a valve is fitted between the turbo and inlet which vents off the excess volume of air. These are known as anti-surge, dump or blow-off valves. They are normally operated by engine vacuum or by electronic control.

The primary use of this valve is to prevent damage to the engine by a surge of compressed air and to maintain the turbo spinning at a high speed. They can also be used as a bypass valve to control boost in a similar fashion as a waste gate, but this is rarely seen as it is impractical. The air is usually vented to atmosphere, or can be recycled back into the turbo inlet. Recycling back into the turbo causes the venting sound to be reduced but as the excess volume of air is not removed problems may arise.

I'll be interested to see what they come up with....

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05 KC SE Smoke
01 Suzuki 600 GSF
88 Fiero 2M4

I'd guess they are using two turbochargers so that one can be smaller to provide the almost instant throttle response and the larger one to provide the boost needed at higher RPMs to provide the HP.

Currently, some manufacturers are using Turbos with adjustable vanes in the Stator portion of the turbine section. This allows lower exhaust pressure to keep the turbine spinning at a higher RPM, this equals more boost. Then as the engines RPMs increase, the exhaust volume/velocity increases and the Turbos vanes adjust to provide the desired amount of boost. Essentially, this lets one turbo do the job of a smaller turbo and a larger one all in one unit.

For many years, Ford ran the Thunderbird SC, it was a Turbocharged I4 cylinder. It produced more HP than their V6. I don't recall if they offered a V8 or not, I expect they did. Still one advantage, from a sporting stand point the Turbocharged I4 provided the power with a lower weight. Good for handling as its front to rear weight bias was more neutral. I took one for a few laps, but ended up buying a Honda Accord....go figure

Red

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2005 Titan KC SE, Helwig, True-Track, ARE MX Canopy