Harley Davidson Carburetor Main Jet 27417-76 on 2040-parts.com

Suburban Terror: Hennessey offers upgrade packages for GMC SUVs

Lest you think that Hennessey Performance Engineering will only tune up your Dodge Viper or Cadillac CTS-V, feast your eyes on this little number showing one of the company's souped-up SUVs taking on a 2011 Nissan GT-R. It's really an unfair fight: The Cadillac Escalade sports a 6.2-liter V8 which in stock form makes about 400 hp. But Hennessey, not looking for a beatdown, drops a twin-turbocharged 427 cubic-inch LSX engine with high-flow cylinder heads, intake and exhaust upgrades, a performance camshaft and a laundry list of other parts to bring the truck's output to 1,000 hp.

Driving age to be raised to 18?

A government-commissioned report has recommended probationary driving licences are in future issued from the age of 18, not 17 – and that learner drivers would be required to invest big in getting a licence. The new proposals would still see provisional driving licences issues from 17, allowing learners to get out on the road under supervision. However, learners would have to undertake a 12-month ‘learner stage’, in which they’d have to cover a minimum of 100 hours’ supervised driving.

JCB DieselMax

Following its display at the Goodwood Festival of Speed last month, the JCB DieselMax has recently proved itself the fastest yet diesel-powered car during Speed Week at the Bonneville Salt Flats, Utah. Andy Green, who in 1997 broke the sound barrier on land in Thrust SSC, piloted DieselMax to reach a top speed of 350.09mph, increasing the existing record set in 1973 by over 100mph. Helping the JCB DieselMax achieve this is a drag coefficient of just 0.174 and two 4.4-liter four-cylinder engines, each producing 750PS.