Arias Pistons 12.5:1 Compression 82mm Bore Honda B-series on 2040-parts.com

Citroen C-Cactus concept's green secrets

By Tim Pollard Motor Shows 17 September 2007 12:52 Citroen C-Cactus: the lowdown Citroen’s C-Cactus concept car on show at Frankfurt signals the start of a programme to investigate simplifying the construction of its cars –stripping out unnecessary weight, complexity and emissions from its everyday hatchbacks and saloons. And it’s not as far flung as it looks. Its designers told CAR Online that this concept wasn’t about the external design, but rather the way the project was conceived and built.

Think City EV Cup Edition (2010) first official pictures

Manufacturers have been trying to make their racers more economical for some time now; Audi and Peugeot have produced diesel Le Mans winners and CAR reviewed the Porsche GT3 R Hybrid in the June 2010 issue, but this the most recent fully electric offering from Norwegian company Think.   Think has followed the traditional road-racer conversion for this one-off prototype, by stripping out most of the interior and space for the passenger, using Perspex instead of glass in the windows, installing a solitary lightweight bucket seat and lowering the centre of gravity. The company claims the diet reduces the Think's weight by nearly 70kg; that's the same saving as a Lamborghini Gallardo Superlegerra, remember.

ZF boss thinks 9 speeds is enough for transmissions

The nine-speed transmission might be where the race to add gears ends, ZF Friedrichshafen CEO Stefan Sommer said. He referred to nine speeds as the "natural limit" because going beyond that number adds weight and complexity that cannot be offset by gains in fuel efficiency. "There is no hard line, but you have to consider the law of diminishing returns.