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

London's GPS-based speed-limit trial puts Big Brother's foot on the gas pedal

A fleet of 12 Toyota Priuses in London have been fitted with GPS-linked speed limiters to measure how drivers respond to having their speed controlled by a computer rather than their own feet. For now, the trial is local to London, run by Transport for London, the agency that manages the city's roads, buses, subways and trains. The agency is using its own fleet of Priuses for the test and will add a bus and a taxi later this year.

GMC Granite at the Detroit motor show 2010

This is the GMC Granite, a new concept car unveiled by GM at the 2010 Detroit Auto Show. Designed to move away from GMC's current range - which is dominated by pick-up trucks and full-size 4x4s - the Granite is much smaller than any GMC currently on sale. Yes, the Granite is just 4097mm long, making it shorter than a Ford Focus or BMW 1-series.

Mercedes CLS Shooting Brake by Brabus (2012)

Mercedes tuning specialist Brabus has unveiled a raft of packages for the new CLS Shooting Brake. A range of tune-ups, body addenda, alloy wheel designs and sports exhaust packages are to be offered, but the real headline act is the 611bhp option for the flagship CLS63 AMG variant. It's not just a mad-cap power struggle though; Brabus offers a three-year/62,000-mile warranty on all its power upgrades, so bear that in mind if the other half isn't convinced your new family estate needs McLaren 12C-chasing poke.