Tuesday 8th September 2009

Lotus Unveils 'Range Extender'

New three-cylinder Lotus lump designed for hybrid car makers

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It's rare that a three-cylnder 1.2-litre motor gets our juices flowing here at PH Towers, but Lotus Engineering's new 'Range Extender' engine is more interesting than most.

Have no fear, sports fans, as the Range Extender is unlikely to find its way into a Lotus-badged product any time soon - Lotus Engineering's primary focus is to develop technology for other manufacturers to use.

It's been designed as an off-the-shelf engine for any production series hybrid, and could be sold to any number of car companies. Okay, so that's not particularly exciting in itself, but it's surely a rather nice potential money spinner for Lotus - and that means more development cash for proper sports cars.

The Lotus Range Extender could even find its way into a Jaguar, as it's been developed with Jaguar as part of the UK Technology Strategy Board's 'Limo-Green' scheme, a project funded by Lotus Engineering, MIRA, Caparo and Jaguar. If the new engine does end up in a series production Jag, it could be part of the company's project to make an executive saloon with a CO2 output of less than 120g/km.

What's really clever about the new engine, says Lotus, is its design: the cylinder head, block and exhaust manifold are all integrated into one casting, creating what the boffins at Hethel call a 'monoblock'. This eliminates the need for a cylinder head gasket and around 17 other separate parts. The weight of the unit is also reduced, while durability and fuel consumption are both improved.

Technical specification

1.2 litre 3-cylinder with 2 valves per cylinder, SOHC
Belt driven
Construction
Monoblock with Integrated Exhaust Manifold
All aluminium
Balance shaft (optional)
Direct-coupled generator
Bore and Stroke: 75.0 mm x 90.0 mm
Compression ratio: 10:1
Maximum power: 35 kW (47 bhp) at 3500 rpm via integrated electrical generator
Peak torque: 107 Nm at 2500 rpm
Maximum BMEP: 11.2 bar
Maximum Engine Speed: 3500 rpm
Fuel System: Port fuel injection, Lotus EMS
Fuel: 95 RON ULG / ethanol / methanol
Dry weight:56 kg

[stuart-b]

The idea seems good, but power and RPM seem rather limited? How come it only revs to 3,500 rpm?? Surely this will make it pretty tiring to drive? As max power is max RPM.

Not sure what car over 500kg, could make use of this?