He's talking shit mate



The ST engine features a combination of performance engine technologies cleverly packaged under the bonnet. Central to these is the ST's approach to delivering stronger power and torque outputs when needed most by the driver:


New, high-flow aluminium cylinder head with larger inlet valves and higher-lift intake and exhaust camshafts for higher peak rpm levels;
Continuously variable intake valve timing;
High compression, cast-aluminium pistons and forged steel connecting rods
Dual mass flywheel;
New dual stage intake (DSI) manifold, using long runners for low-end torque and shorter runners for higher peak power outputs;
Larger bore free-flowing stainless steel exhaust system, tuned for enhanced performance sound.

To develop the Focus ST170 powerplant, Ford engineers provided a number of engineering enhancements, including improved gas flow characteristics, higher rev capability, combustion efficiency and a higher compression ratio.

Duratec ST's new aluminium cylinder head features enlarged intake ports to increase its flow potential. It is fitted with larger intake valves (33.5mm) to further increase Duratec ST's free-breathing character. Stiffer springs on both the intake and exhaust valves help to facilitate a higher redline. Focus ST170 has an indicated red line of 7200 rpm on the tachometer for continuous operation and rev-limiter intervention beginning at 7400 rpm.

Duratec ST's new dual-stage intake manifold provides additional technology to enhance power and torque. At lower engine speeds up to 6000 rpm, the intake configures itself to enhance the torque characteristics that are central to the ST170 driving character.

Above 6000 rpm it reverts to a higher-power-output configuration.

Constructed of composites, the intake manifold features four tuned runners that can be adjusted in length. In its closed position, for maximum torque, intake air entering the plenum is directed through long runners. At higher speeds, the runners are rotated into an open position, directing intake air immediately into the intake port. This is power configuration at the top end of the rev range.

Duratec ST also features a low-loss air filter to further enhance its breathing flow.

Fuel is delivered to the cylinders via an electronically controlled, high-output fuel pump. With precise electronic control of the fuel delivery to the injectors, no return fuel loop is required. The system contributes to ST170's Euro Stage IV emissions capability.

Variable valve timing technology (VVT) gives Duratec ST combustion efficiency that eliminates the need for a close-coupled catalyst in the exhaust system. This enhances its flow characteristics and performance capabilities further.

Duratec's intake camshaft is equipped with an electro-mechanical control mechanism that allows the cam's maximum opening point, relative to crankshaft degrees, to be varied between 85 and 145 degrees after top dead centre. Variability is calibrated according to engine speed, load and operating temperature. It is accomplished by changing oil pressure on either side of a piston in a helix between the cam and its drive pulley.

On cold start- up, VVT helps to provide a precise combustion calibration that facilitates quick light up of the underbody exhaust catalyst before adjusting to a profile for high-combustion efficiency. As a result, Ford engineers were able to position the catalyst unit (incorporating premium metallic elements), approximately 900mm away from the cylinder head face to give Duratec ST its free exhaust flow with reduced back pressure. A second catalyst unit is located downstream in the exhaust.

The exhaust system is constructed entirely of stainless steel, tuned for its throaty performance sound. Its exhaust manifold, cleverly designed for package efficiency in the Focus engine bay, is created of equal-length tubular headers in a four-to-two-to-one configuration. The design combines the first and fourth cylinder exhaust tubes and the second and third cylinder exhausts, respectively, before the resultant two pipes are combined into one to enter the catalyst. The exhaust pipe diameter is 65mm.

Despite its performance characteristics and the lack of a close-coupled catalyst, the new Focus ST170 retains its Euro Stage IV emissions performance, to comfortably exceed ADR requirements.

Ford's engineers used the production 2.0-litre Zetec engine as the foundation for the Duratec ST performance version. Its cast-iron block provided the ideal strength, rigidity and durability necessary for higher output.

Robust elements were incorporated in Duratec ST's top end to reflect the additional performance demands being placed on the engine. These include stronger, lightweight, cast aluminium pistons with larger, 20mm wrist pins and robust, sinter-forged connecting rods.