1986 Holden Commodore: No looking back

THE PROSPECT of a Holden Commodore powered by an imported Japanese engine was greeted with derision when it was first mooted early in 1983.

We won't let it happen, said the unions; who's going to buy one, scorned long time Holden customers; even the specialty press wondered if it could possibly be true.

Finally, after rumour and counter-rumour, fuelled by GMH and Nissan's mostly successful attempts to prevent the publication of specific details regarding the engine and its performance, the VL Commodore, with its fully imported Nissan three litre single overhead camshaft straight six, is a reality.

Putting aside the emotion involved in Holden's ceasing production of six cylinder engines after 38 years (not an easy thing to accept for many people who still consider it Australia's Own) the result is a quieter, smoother, more economical car with superior performance. For many people that will be enough and they won't care or know what the motive power behind their new car is, or where it comes from, provided it is reliable, starts easily and performs to the required standard.

The new engine isn't the only important aspect of the release of the VL. The car gets a major facelift, new transmissions, the first real interior-lift since the Commodore was released in 1978 and significant modifications and (mostly) improvements to the suspension and chassis. For the moment the entire range is restricted to just the new engine with either five speed manual gearbox or the four speed automatic transmission (both of which are imported from Nissan in Japan) regardless of model level.

The locally made 4.9 litre V8 engine isn't dead, however, but will be reintroduced in lead-free form in September, and a turbo six a little later. In its quest for a new six cylinder engine to meet the January 1, 1986, deadline for lead-free fuel, Holden searched the world. The Fishermens Bend budget never did stretch to a new locally designed and manufactured engine (not after spending $400 million on the as yet unprofitable Family II four cylinder plant) and despite the vast resources of its parent company none of GM's engines was considered suitable for the Commodore. Opel's existing six is an old design and very heavy; it has also never been tuned to run on lead-free fuel, and its replacement wasn't considered appropriate on technical grounds; the new V6 engines from the USA weren't powerful enough.

The alternative was to approach various competitive car makers in an attempt to find the right unit. Even Jaguar was asked about its new 3.6 litre single ohc six. Finally Nissan, with whom Holden was developing a close working relationship, in late 1982 lifted the lid on its then yet-to-be-released RB/RP straight six engines and Holden's then chief engineer, Joe Whitesell, realised he had found the Commodore's new power plant. A deal was struck and a new development program began on the three litre version for Australia. Will this same engine also appear in the new Skyline in April/May?

Nissan's new engine- it says Holden on the cam cover of the engine, but don't take that too literally - is an in-line six with bore and stroke of 86 x 85 mm for a capacity of 2962 cm3.

While it is being billed as a "new" engine, in reality it is a heavily reworked version of the old Nissan straight six as used in the Skyline and 280ZX, with a shorter block, a new crank and toothed belt drive to the overhead camshaft. The cross-flow cylinder head is alloy (but the block is iron) and it uses Nissan's version of Bosch electronic fuel injection. Despite its apparent new generation specification the engine weighs 218 kg, or 11 kg more than the old injected six when both are fully dressed and ready to run.

An engine management system using a sophisticated microcomputer controls the fuel injection, ignition timing, idle speed control, fuel pressure control, fuel control and self diagnostics. The result is an engine that develops 33 percent more power than the old carby six and yet uses 15 percent less fuel. The VL Commodore develops 114 kW at 5200 rpm and 247 Nm of torque at 3600 rpm, compared to the previous carburettor engine's 86 kW at 4200 rpm and 232 Nm at 2600 rpm, and the injected engine's 106 kW/4400 and 266 Nm/3200.

During the engine development in Australia the key priorities were to secure high torque at low and intermediate speeds, to build in responsiveness and to reduce engine noise and vibration. Nissan sixes have never been famous for their bottom end performance and Holden's engineers worked hard to reach their targets, even at the cost of ultimate top-end power.

The result, however, is a high performance sedan that is going to blow most coupes and European sedans into the weeds and will give Ford cause to ponder an effective answer to Holden's fuel injected challenge. The engine is flexible and responsive and pulls strongly from 1000 rpm in a gutsy manner that will please long time Holden owners who want to believe this is the way all cars should behave. What is very different about this Holden is that the engine will then it pull cleanly, effortlessly to the redline that is a BMW-like 6200 rpm. There is an cooling is provided through if the bumper bar.

Every panel forward of the A-pillar has been changed - even the vent cowl immediately in front of the windscreen - and the bonnet slopes down more steeply although only 25 mm has been added to the overall length. The car looks longer and wider (for obvious reasons not just related to the Falcon) and if it does have a touch of the "final facelift" look that is not surprising.

Technically the body changes include a switch to a bonded windscreen and the use of homofocal headlights that improve high beam intensity by 85 percent and penetration by 35 percent over the VK Commodore.

More welcome than the exterior styling changes are the new instruments and controls. Gone are the horrid square gauges of the VK and in their place are a round speedometer and tacho (on Berlina and Calais) with small rectangular minor gauges. The electronic dashboard of the Calais has been dropped (a last minute decision based on reliability, such is Holden's emphasis on quality these days), and along with it has gone the trip computer though they will probably return with the next model. So the Berlina and Calais share the same instruments, while the SL makes do with a large clock in place of the tachometer and fewer minor gauges.

The top of the dashboard has been drastically changed so that it doesn't look as heavy as the previous Commodores, and even the floor pan has been changed to allow more leg room around the transmission. There are now small satellite controls with touch buttons at the extremes, and they work effectively although they aren't quite at finger-tip length from the wheel.

The Calais carries on with a newly designed single spoke steering wheel of slightly smaller diameter than the new two-spoke wheel of the other models, but it shares the same central console, with its deep bin armrest between the front bucket seats, with the Berlina.

The front bucket seats are new in the Calais and orange warning zone at 5600 rpm but it is a warning only and the 6200 is there to be used (there's an electronic cut-out at 6300 rpm). On Holden's speed bowl the VL Commodore - and remember this is the base fleet owner's car -- proved it was capable of over 190 km/h ...

Out on the winding roads of Gippsland the VL was equally impressive, the performance entirely useable and that similarity with a non-ETA BMW perfectly valid. The engine's marvellously broad rev range means that with the manual gearbox any of the three upper ratios can be used in virtually any driving situation.

Equally, the quality of the gearchange, with its hydraulic clutch, ensures another side of the car has been dramatically improved. It's much slicker and more precise, and far easier and more enjoyable to use. The ratios are tall in the extreme, even by today's standards - second will pull to over 100 km/h and third almost to 160 km/h. But the engine is able to cope so efficiently you come to the conclusion that the gearing is close to perfect. The direct fourth gear ratio gives 32.9 km/h per 1000 rpm while the overdrive fifth with the 3.45 final drive ratio produces 43.4 km/h per 1000 rpm.

The Nissan automatic is even taller in its gearing, the lock-out overdrive fourth gear - its button very conveniently located on the right of the console mounted selector – giving a massive 47.9 km/h per 1000 rpm using the same final drive ratio as the manual cars. Cruising is effortless and quiet, hardly surprising since at 100 km/h the engine is only turning over at 2100 rpm, while even the direct third gear at the same speed only has the engine working at a lazy 3000 rpm.

The automatic is set to change up at 5200 rpm, and while there is some hunting, especially when the overdrive is switched in, it changes up smoothly and complements the engine perfectly. There are two shift patterns controlled by another button for normal and power modes; these alter the part throttle change-up points by about 10 percent.

Holden's performance figures are generally conservative and since they are a mean of a number of tests on a variety of cars we have no doubt that our road test figures will prove to be even more impressive than those quoted by the General's men. The manual sedan should cover the standing 400 m in just 16.7 seconds while the automatic takes 17.5 seconds and the heavier Calais 17.8 seconds.

We've timed the old injected VK auto at 17.2 seconds and fully expect the VL to beat that, while a 16.5 second 400 m time is highly likely from an SL manual. With its crisp exhaust note, sharp responsiveness and quiet, easy manners this car is going to appeal both to the enthusiast and to the tired company man who has to struggle home in the commuter traffic.

The engineers also went noise hunting, using a new method called acoustic intensity which allowed them to measure both the level and direction of sound, much of this work being done on the VL in Detroit. The result was that high noise areas were pinpointed and almost eliminated. Other work aimed at lowering the overall noise level saw additional body silencing used, the exhaust system very carefully mounted, and bracketing strengthened to reduce the risk of vibration. There is no question the engineers succeeded, but in doing so a long-tirqe Commodore noise area has become even more obvious: wind roar from around the A-pillar is now palpably excessive. It seems, however, that a cure will have to wait until the new-bodied 1988 VN model.

The changes to the chassis include switching from linear rate front springs to progressive, while the front geometry has been reset. At the same time the manual steering gear is now of the variable ratio type and the linkages have been relocated forward and down to reduce toe-out and roll steer and make the car more predictable on loose surfaces. There are 4.6 turns lock to lock with an on-centre ratio of 19.7:1 which goes out to 24.5 on lock. The old rack and pinion system was 19.9:1. The power steering, too, has changed to a variable ratio set-up and is now engine-speed regulated. The on-centre ratio is 17.2:1 reducing towards full lock to 11.8:1 while the previous power steering had a ratio of 15.8.

The change has been made because a number of drivers (not, we should add, those at WHEELS) felt the power steering was too sensitive, nervous even, in that first movement away from the straight ahead. We like the instant responsiveness but many people found, especially on gravel roads, that it gave the car an unpredictable feel. On paper the new power steering seems more direct with 2.7, instead of 3.3, turns lock to lock. Certainly the VL is less skittish at the tail but equally it is slightly less quick to respond to tiny steering wheel movements, and therefore less accurate. The real enthusiast will probably be disappointed with the change, at least on bitumen roads, but most people will probably welcome it.

The ride is softer, too, and there is more body roll, but the handling is now so predictable that even people raised on manual steering Falcons will find it relaxing to drive. There is perhaps marginally more understeer in most conditions, but a final judgement will have to wait until we can put it over our road test course.

The other area of major change, obviously, concerns the body. It seems that with its home-grown products Holden will never again fall into the trap of releasing a new model that can barely be distinguished from the old. The VL gets an entirely new nose with distinct differences between the Commodore and the luxury Calais, while at the rear there is a new boot lid that has a small upward sweep to create a mini spoiler. No drag co-efficient, but GMH claims the VL is five percent more aerodynamic than the VK. The new nose brings heated discussion. There are some who think it is ugly, others who find it new and attractive.

The Commodores get Camira-like headlights - shared with the Calais, though the styling disguises this fact - and a small two-bar grille; additional completely retrimmed versions of the old in the other models. The rear seat has been revised around the wheel arches to make it more comfortable for three adults and a dead pedal has been added on all models.

Last year 53 percent of all Commodores sold were the Executive version of the SL - with automatic transmission and power steering - and with the VL it seems this has become a model in its own right. Certainly the Calais, despite the styling differences, doesn't seem to be sufficiently different to the Berlina in equipment levels and interior treatment to justify the price differences anticipated at press time.

But the new engine and gearboxes are a giant step forward, the car's mechanical sophistication is quite outstanding and the changes to the interior sensible and practical, as well as being visually appealing. The Falcon just might have trouble holding sales leadership over the Commodore in '86.