review from www.fastlane.com.au

Holden Calais Supercharged V6

Most Australians have long been convinced that a V8 is the only real answer to Australia's long distance demands.

Understandably, many vee-devotees were distraught when the oil crisis of the early eighties saw Ford drop V8s completely, leaving Holden to champion the cause alone until 1991, when Ford saw the light and reintroduced a 5.0 litre V8 to its model line-up as an option.

While upgrading its 3.8 litre V6, Holden continued to offer its own lusty 5.0 litre V8, which was carefully nurtured as Australia's only biggie for all that time, so in a way it seems ironic that Holden introduces a 6-cylinder engine that could challenge the V8, basically an "Ecotec" V6 with a supercharger bolted on top.

For the uninitiated, superchargers and turbochargers both do essentially the same thing; provide a quantity of compressed air which is pushed into the engine's combustion chambers along with the fuel, for more efficient combustion and greater power.

The two differ in how the compressor is run, a turbocharger being basically a fan which is driven by the engine's own exhaust gases while a supercharger is driven by belts or gears running off the crankshaft. Some turbos are criticised for being slow to develop their extra power and torque, but superchargers (or blowers) give more of their oomph without hesitation at low rpm, and over a wider range of speeds.

The blown V6 is expected to be optional in the awaited VT model Commodore, but in the present VS model is offered only in the upmarket Calais or Statesman variants. The new engine was apparently a big factor in Statesman being voted 1996's best luxury/prestige car in its price segment by both the NRMA and RACV, but we met it in a Calais - a Commodore in formal dress.

In terms of appearance and interior trim the test car was like any other Calais, which means a bit of opulence, extra sound deadening material and every power gizmo possible. In fact, with no wings, scoops or massive tyres, the only visible signs of something suspicious are the discrete chrome badges and an unusually large exhaust pipe ...Still using pushrod-activated overhead valves in this era of overhead camshaft engines,

Holden's V6 has evolved in its current "Ecotec" guise into an acceptably quiet and smooth powerplant, and the `blower' version feels completely unchanged in both respects, as long as the accelerator pedal is left alone.

But start tromping on that pedal, even lightly, and the difference is obvious.

Although early prototypes are rumoured to have outpowered the 5.0 litre V8, the V6 now pumps exactly the same power and near as dammit to the same torque, enjoys vastly improved throttle-response at lower rpm, and has a decidedly muscular feel to it which proved equally suited to heavy traffic or the open road.

There are actually two different sides to its character. At low revs it feels more like a V8, pulling like a bull in springtime thanks to its healthy torque delivery, yet as the tacho needle climbs further round the dial it feels more like a hi-tech twin cam gadget, with bags of top-end power.

It prefers to run on premium unleaded petrol, and with the automatic in "economy" mode around town it took an uncommonly heavy kick on the throttle to change down at even moderate speeds, so I consequently ran two city economy checks, getting 13.5 L/100km (21mpg) in economy mode and 11.2 L (25mpg) in power mode.

Strange really, but the highway figure of 8.6 L/100km (33mpg) was ample compensation because on the open road the test Calais felt at its best, cruising at 110kmh on 2,000rpm, smooth and quiet with just a discrete whistle from the supercharger when overtaking slower traffic (which never took long).

The V8 has ruled for a long time, but now faces a real challenge in the form of a V6 which can make buyers question whether they actually need eight cylinders at all, a question Ford may be pondering for its own reasons.

It is probably only a matter of time before the supercharged V6 gets the Holden Special Vehicles treatment, to give the Tickford-tuned Falcon XR6 a scare just like the one Fairlane and Fairmont and Fairmont are already being dealt by its use in the plush Statesman and Calais.

Even for those who want to tow heavy trailers, Holden is certainly proving that, in this case, six really can equal eight.