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

Fiat unveils new 900cc TwinAir two-cylinder engine

Fiats of old used to feature noisy two-cylinders with a fetish for overheating, yet the Italians are at it again, this week releasing details of their new TwinAir two-cylinder 900cc engines. You can see how it works in our video below. The new engines, the first in a series of two-cylinders by the Italians, are designed to trump all other downsizing efforts. Headline figures from the 83bhp twin are 23% more power than the regular 1.2 four-pot and the same as a 1.4 16v - yet with 30% less consumption.

McLaren 650S Sprint revealed – debuts at Pebble Beach

The McLaren 650S Sprint arrives to hit the track The arrival of the McLaren 650S in February (and the end of the 12C, unless it’s being replaced by the McLaren 625C) meant, in all probability, that the various hardcore versions of the 12C would be replicated for the 650S. We’ve already has the new McLaren 650S GT3 at Goodwood this year, and now we get the car that fills the gap between the 650S and GT3 version for McLaren owners to take to the track – the McLaren 650S Sprint. The 650S Sprint – which we assume replaces the 12C Sprint – keeps the 650S’s 641bhp V8 but adds a hefty dose of track specific updates to make the Sprint more focused and with sharper responses.

2014 Citroen C4 Cactus: pictures and full details

The 2014 Citroen C4 Cactus has been revealed ahead of the car's official debut at the Geneva motor show next month. The all-new model is the first in Citroen's new C-Line model range and introduces a world-first, in the form of  'Airbump' - air-filled plastic panels at the front, rear and sides of the car which are designed to protect the bodywork from minor bumps and scrapes . The C4 Cactus production car closely resembles the stiking concept car of the same name that was unveiled at the 2013 Frankfurt motor show and it will be one of the most distinctive cars on the road when it goes on sale in the UK in October.