BY TIM BRITTEN | 10th Aug 2004
In fact, the new 3.6-litre V6 is so much like the now-departed, 3.8-litre ex-Buick cast-iron plodder that at first one is tempted to check under the bonnet to see that’s not actually the case.
It even drives a bit like the old engine – reasonably meaty in terms of torque output, but not really fond of a rev.
The latter proves to be merely an impression of course the new engine’s 5500rpm redline, when you push it, seems quite conservative when you remember maximum power doesn’t arrive until 6000rpm in the regular Alloytec, and 6500rpm in the 190kW version. And yes, there appears to be a little more acceleration and a little more fuel economy.
The problem is, the differences are incremental only. The overhead camshaft Nissan six (like the Alloytec, also smaller in capacity than its primitive predecessor) dramatically changed the VL Commodore’s general NVH, while adding noticeably to performance and improving fuel economy.
The Alloytec replaces old technology with new, too. A cast-iron, pushrod engine makes way for all-alloy construction and state of the art cylinder head design, complete with twin overhead camshafts and four valves per cylinder.
But if you think it’s going to sound and feel something like, say, Mitsubishi’s 3.5-litre V6 – or an inline Nissan six - think again.
Rather than the refined growl of the Mitsubishi, there’s a distant, pedestrian-sounding rushing sound accompanied by – in some cases – surprising clatter from the overhead gear.
Considering Holden has hung its hat on this locally-built - and in line for exportation - engine, it’s more than a little disappointing it doesn’t do for the Commodore quite what some of us expected.
But, if it’s difficult to judge the Alloytec on a purely tactile basis, at least the figures stack up reasonably well.
In the regular version, power is up from the 152kW (at 5200rpm) of the old Buick engine to 175kW at 6000rpm, and torque rises from 305Nm at 3600rpm to 320Nm at 2800rpm.
Interesting. The torque is greater and is produced at lower rpm despite the smaller capacity, while the extra 14 per cent of power comes more predictably, with quite a bit of extra revving.
The answer, largely, is in the variable valve timing that is standard in both 175kW and 190kW engines, except that the more powerful version uses it on both inlet and exhaust camshafts. It applies to just the inlet manifold on the 175kW version.
The separate ignition coils for each cylinder and – on the 190kW Alloytec - variable-length inlet manifold design play a part too.
Fuel consumption is down marginally, according to ADR 8/10 figures, from an average of 11.3 litres per 100km in the previous engine, to 11.1L/100km in 175kW Executive, Acclaim and Berlina.
Similar small improvements apply across the board - except for the subject of this test, the six-speed manual-transmission SV6.
Both the revised four-speed automatic and the new five-speed auto are better than previous figures by more substantial margins – for example the five-speed auto SV6 returns 11.5L/100km where the previous automatic supercharged model returned 12.9L/100km.
The five-speed auto’s high gearing undoubtedly helps here. The SV6’s six-speed manual is high-geared too (nine per cent moreso in top gear than the previous five-speed), but to no apparent avail where fuel economy is concerned.
Mind you, this may not necessarily be the case in real-world applications – our test SV6 was quite thrifty in a mix of mainly urban driving where it returned an impressive average of 10.5L/100km.
Combine this with a decent 75-litre tank (Ford Falcons hold only 68 litres) and the Holden offers a pretty useful cruising range on country trips, where better than 600km between top-ups should be pretty easy.
So how does the VZ SV6 stack up? Does the 190kW engine mean it can go out hunting non-turbo XR6 Falcons?
Well, yes, it stacks up impressively and yes, it can.
Although torque development favours the bigger-engined Ford (380 versus 340Nm), the Holden has more kiloWwatts (190 versus 182kW) and a 100kg weight advantage.
Tall gear ratios do blunt the SV6’s reactions to a certain extent, but it will accelerate smoothly and forcefully if the wide power band – much wider than the old supercharged V6 - is put to good use. The engine works well from 3000rpm upwards, to the 6500rpm needed to produce maximum kiloWatts.
The six-speed manual shift tends towards heavy but is quite positive and free of any baulking between gears. The SV6 also suffers less passenger compartment noise than, say, a 175kW Executive, although the hoped-for exhaust note is still missing.
The overall impression is of a smooth, quite meaty engine that, even if it lacks the tearaway nature of a real sports sedan, gives the SV6 enough punch to justify the mildly tarted up appearance.
Seventeen-inch wheels, a rear spoiler, larger front air dam, side skirts and a littering of black paint outs separate it from Executive models.
Holden has been working away at Commodore steering forever, and the VZ is better than before.
It’s mainly been a matter of tweaking, including a reworking of front stabiliser bar links and the adoption of a new, lighter power steering pump, but it’s undoubtedly a little sharper, even if it’s still not up to Falcon standards. The impression is that it’s all slightly less heavy and stodgy.
Combined with the SV6’s tighter, lower sports suspension, as well as the standard 17-inch alloy wheels and 235/45 tyres, the reworked steering helps make for a nicely balanced Holden. It’s a confident, non-intimidating car.
For the money – well under $40,000 in standard form – the SV6 is not a bad package that picks up a little more gear than an Executive Commodore.
On top of things like air-conditioning, cruise control, auto headlights, a reasonably comprehensive trip computer, dual airbags, anti-lock brakes (with EBD and Brake Assist), the SV6 gets traction control, a leather-rim steering wheel and the bodykit that also includes front "fog" lights.
Not a bad way at all to go the sports sedan route.