The secret behind the new SRT-8 saloon and 4x4 is an overhauled version of the HEMI V8 engine. Usually displacing 5.7 litres, the SRT team has bored out the engine to 6.1 litres. A higher, 10.3:1 compression ratio, revised engine breathing and a redline now pegged at 6,400rpm produce 25% more grunt. Outputs are a hefty 425bhp at 6,200rpm and 420lb-ft at 4,800rpm.
The new Grand Cherokee has ventured into Death Valley to hot weather test the 6.1-litre HEMI. Disguise hides the new twin bulb, Land Rover-esque lamps, but the gaping lower air scoop is impossible to miss. Power is channelled to all four wheels via a five-speed automatic ’box.
A Porsche Cayenne Turbo rival would have been unthinkable on the outgoing big Jeep, but the 2005 edition promises to be far sharper dynamically. The new, independent suspension front and rear combines greater stiffness with increased wheel travel, to improve refinement and on-road precision. The Grand Cherokee also gets rack and pinion steering, for quicker responses and a reduced turning circle.
Other developments include ESP, a crisper look and a fast windscreen to improve aerodynamics. The new model, also running the Cherokee's 208bhp 3.7-litre V6 and a new 3.0-litre diesel, hits the UK next summer.
While the Grand Cherokee SRT-8 is still under wraps, above left is the first official picture of its hot 300C counterpart. Chrysler is predicting a 0-62mph sprint in less than 5.5sec. The suspension is beefed up with stiffer spring and damper settings.
The 300C arrives in the UK in autumn 2005, priced from less than £30,000. The SRT version follows in 2006, priced around £40,000.
300C SRT-8 OUTSIDE...
Body kit includes vents to cool the Brembo brakes and body-coloured grille, mirrors and door handles. Spoiler adds downforce
HEMI V8 bored out to 6.1 litres, while new intake and exhaust systems and a higher redline help produce 425bhp.
Grand Cherokee 4x4 has independent suspension and new steering rack, for sharper dynamics and greater refinement.
Sports seats get suede inserts, while leather trim adorns the wheel and gear shifter.