Back in November 2004 we drove the VZ Commodore SV6 (see Holden VZ SV6 Manual Test) and in January 2005 we tested the VZ Commodore wagon – see Holden Acclaim Wagon. Of course, the VZ is the last iteration of the Commodore that began life with the VT model in 1997, but powered by a pair of new high tech, quad cam, 3.6-litre engines rather than the old pushrod 3.8 litre V6. The quad cam had been an engine we were very much looking forward to and well before its launch, we trumpeted its design in Holden’s New World Class V6. However, as the two on-road tests show, the reality was far less impressive than the on-paper spec.

After driving the SV6 we said of the engine:

If you want to pull ahead of traffic, you are forced to take the 3.6 litre V6 engine to high revs. This wouldn’t be an issue if the engine was a sweet, willing revver – but it isn’t. The engine has a gravelly roar and – in manual gearbox versions – high rpm vibration floods through the clutch and gear knob. And it appears that Holden doesn’t want anyone giving the V6 a big rev. Curiously, the marked redline is at just 5500 rpm (1000 rpm below peak power!) and there are no markings beyond 7000 rpm. The rev limiter is squeezed in at 6700 rpm.

And after driving the cooking version…

It’s impossible to describe any aspect of the engine (apart from its electronic throttle control) as a highlight. Idle quality? – poor, and at times (when heat soaked?) astonishingly poor. Economy? – certainly not outstanding. Performance – nothing to write home about. NVH? – hell no.

And talking about fuel consumption, it was relatively poor in both tests – 9.2 litres/100 in the case of the auto wagon driven about as gently in open road cruising as possible and nearly 15 litres/100km in urban conditions in the SV6.

However, the VZ is a good car in other respects – handling, ride, space, equipment. So when I recently needed to hire a large car while interstate, I selected a VZ Commodore 4-speed auto wagon. Unlike the two previous test cars (both supplied by Holden with relatively low kilometres), the hire car had over 30,000 kilometres on it and had probably – like most hire cars – been driven hard for that distance.

Now I don’t know if Holden is responding to widespread criticism of the quad cam engine by making running changes, or it was simply because this car had far more kilometres under its wheels than the previous cars we’ve driven, but the engine in the hire car was clearly improved. Unlike the test wagon, the hire car’s auto trans needed to make far less down-changes when confronted with hills (ie mid-range power was improved) and when the engine was taken to high revs, it was less noisy and harsh than the previous engines we sampled. It certainly wasn’t transformed into anything remotely class-leading, but it no longer stood out like a sore thumb for its appalling behaviour.

And the fuel consumption also seemed better! It’s very hard comparing fuel consumption figures across different types of driving but based on our previous experience, I would have expected consumption around 12.5-13.5 litres per 100. Instead, we recorded 11 – 12.5 litres/100km.

With its high degree of technical specification and all-new design, the Holden quad cam V6 should be the best engine available in Australian-built cars. Instead the Falcon in-line six just kills it, the Camry’s V6 shows a sweetness that age has not dulled, and the Mitsubishi 380’s engine shows what good engineering and a lack of development money can still achieve from a basic design.

So despite the hire car experience, I still don’t think the Holden V6 is anything to get excited about. It’s just that I’d no longer rate it as awful – perhaps ‘workmanlike’ is a better single word description.