Peugeot-208-Hybrid-Fe-03

We first got wind of the Peugeot 208 HYbrid FE at the Geneva show earlier this year, but its presence at the show was only a teaser, with no actual car or real technical details revealed. The 208 HYbrid FE makes a proper debut at the Frankfurt show happening next month, and here are the initial details.

The hybrid 208 is a collaboration between Peugeot and Total. It’s a full petrol hybrid without plug-in functions. Acceleration is relatively brisk – it is said to be able to hit 100 km/h in eight seconds despite having just a three-cylinder engine – this is a big improvement over the 14 seconds that a regular Peugeot 208 with a 1.0 litre three-cylinder engine takes.

The 208 Hybrid FE’s body is 25% more aerodynamic than a regular production 208. Modified body parts include a more aerodynamic body and roof design, a smaller front grille, bespoke low-resistance 19-inch Michelin tyres that are tall and thin, and rear cameras in place of door mirrors. Rear track is narrower by 40 mm.

Peugeot-208-Hybrid-Fe-04

There are big changes to the 208’s 1.0 litre three-cylinder motor in the base car. The engine is modified to use the Miller combustion cycle, and compression ratio is increased from 11:1 to a high 16:1. Such a high compression ratio increases chances of knocking, so Peugeot took some steps to avoid this.

The rate of unburned elements in the combustion chamber is reduced by valves of increased diameter, exhaust pipes are redesigned, as is the manifold, and an adapted valve lift pattern is introduced. Furthermore, the heat exchanges are optimised in the cylinder block by means of coolant passages arranged between the cylinders. The coolant now passes through the cylinder head along its entire length to recover the heat around each source: combustion chambers, between injectors and spark plugs.

Fuel injection switches from regular port injection to direct injection, which allows more precise measurement of fuel. The nitrated steel crankshaft, the titanium con rods and the aluminium-copper alloy pistons are cut from solid so they are lighter. Finally, the engine displacement has been increased to 1,233 cc by increasing both the bore and stroke to 75 mm by 93 mm.

Peugeot-208-Hybrid-Fe-01

The weight of the cylinder head, also cut from a solid block, is halved due to the reduced thicknesses permitted by its design and the characteristics of the aluminium used. The coolant circuit and the inlet line are made by rapid prototyping of resins charged with glass fibres or carbon. To do this, the laser beam of a 3D printer fuses successive layers of aluminium powder. This produces a functional component quickly and more cheaply in the context of individual specialised manufacture.

Peugeot claims friction losses which typically consume 20% of the engine power have been reduced by approximately 40%. A special 0W12 grade engine oil of extremely low viscosity has been developed by Total Lubricants using ultra-fluid based oils and by the addition of friction reducing agents containing molybdenum. Together with the other optimisations, the engine maintains the 68 hp rating of the unmodified engine while being more fuel efficient.

This engine is paired to an electric motor which is said to be built with the expertise gained from racing the Peugeot 908 HYbrid4 race car. The motor is only 7 kg, and develops 30 kW as a motor and 100 kW as a brake generator. Maximum torque is 30 Nm, and it can spin up to 40,000 rpm. It is able to power the car alone in zero emissions mode. It’s powered by a lithium ion battery consisting of 90 V cells, weighing 25 kg. It’s installed with the 20-litre petrol tank on a subframe which is bolted under the rear bench seat.

Peugeot-208-Hybrid-Fe-02

The 208 HYbrid FE’s gearbox also has weight reductions. The casing is cut from a solid block. To reduce friction losses, the teeth of the gears are given a tungsten carbide chrome coating. Greasing is redesigned to reduce the volume of lubricant necessary and prevent splashing over the gears, which also consumes energy. The prototype gearbox oil is developed by Total Lubricants based on bio-sourced oils, of 75W grade with a very high viscosity index (higher than 250). This produces a 3% reduction in consumption.

With all the improvements above, you’ll see why 14 seconds in a normal 1.0 litre 208 drops to 8 seconds with this concept 208 hybrid All in all, Peugeot says the weight reduction, aerodynamics and tyres contribute about four seconds to the improvement in acceleration, while the electric motor reduces another two seconds. The air conditioning is gone too, by the way

We’ll put up a proper gallery of the 208 HYbrid FE when Peugeot releases it.