The Holden 3800 V6, as fitted to the VN Commodore.
Before The V6
Holden's had been traditionally powered by the trusty Grey, then Red engines. These were very good motors, easy to work on, easy to find parts, reliable and, while not offering startling performance, they had developed a solid reputation.
But by the mid 1980s Holden knew they needed
something more - particularly due to the intriduction of unleaded petrol. Aside from featuring a completely new front-end appearance, the controversial VL Commodore was powered by an imported Nissan 6-cylinder engine.
The new model, released in February 1986, was heavily criticised with many thinking it sacrilege to give Australia's own car a Japanese powerplant. After driving the VL, however, most critics realised that Holden had given its buyers the best 'six' yet seen in an Australian-built car.
While Ford had made the compulsory switch to unleaded fuel (in February 1986) by fitting the Falcon with a modified version of its old engine, Holden had a considerably better Commodore. Power was up 33 per cent and fuel economy was 15 per cent better.
Among the features in the state-of-the-art engine was a self- ~ diagnostic module designed to detect and memorise mechanical faults. But the best was yet to come, because in the second half of 1986, a turbocharger was introduced as an option across the range. The standard Commodore was quick off the mark but the 150 kW VL Commodore Turbo could accelerate to 100 kph in eight seconds and reach a top speed of 220 kph.
Which Engine To Power The VN?
Later in the year, the locally made 4.9-litre V8 (now modified for unleaded fuel) was re-released as an option on the VL. When the replacement VN was in the planning stage, the aim was to use a modified version of the imported Nissan straight six (rebored to 3.3-litres) plus the V8 with fuel injection, if it could be ready in time. Other alternatives considered, including reboring and rejigging the faithful 3.3 Holden-engine, and slicing the last two cylinders off the V8 to make a 3.8-litre V6. There were even thoughts of welding a couple of extra pots on to the Family II 4-cylinder engine or even producing the Nissan engine locally.
The Buick V6
The route eventually taken, however, was to locally assemble the 3.8-litre V6 used by Buick, Oldsmobile and Cadillac. The American V6 had evolved from a 1962 design but was being completely redesigned by the Americans for a 1988 relaunch. Although still slightly primitive in mechanical specification, this pushrod donk performed well and had bags of torque. In the US it was only being built for front-wheel drive and for use with an automatic, so the GM-H engineers had to turn the east-west engine north-south and adapt it for the two transmissions planned for local use: the M78 5-speed and the MD8 Turbohydramatic slushbox.
One of the improvements the Americans had instigated for the 1988 V6 included the use of a balancing shaft for smoother running. When the American modifications were combined with the locally adapted fuel injection and engine management systems, the result was a powerplant which stacked up very well indeed. Aussie motorists took to the new six enthusiastically but, once again, the best was yet to see the light of day. Although the fuel-injected V6 made the Commodore so quick that some preferred it to the carburetored V8, Holden engineers were busy working on a port fuel-injected (PFI) V8 which was better again.
With 165 kW at 4400 rpm and 385 Nm at 3600 rpm, this V8 turned the VN Commodore into what was possibly the world's fastest family car. Even the off-the-shelf base model was 10 per cent quicker than the Turbo VL or the carburetored VL Group A. And it was quiet, smooth and flexible to boot. Owners discovered it would smoothly accelerate from 30 km/h to 220km/h without a gear change.
