Brock Built: The Brock Car-Enhancement Legend

By: David Morley, Photography by: Unique Cars Files

Inspired and never boring, Brock cars were often one-offs - much to the chagrin of GM

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Brock Cars

Peter Brock’s HDT car-building business was not like other places where raw materials go in one end and cars come out the other. Nope, you see, you weren’t just buying a car when you lined up for an HDT Commodore; you were also buying a slice of the Brock magic. And that counted for plenty.

In line with Brock’s own massive self-confidence, his uncanny feel for cars and his sheer enthusiasm, the HDT operation was to car-making as a back-alley game of two-up is to the Monte Carlo casino. I’m not suggesting for a moment that HDT ever did anything dishonest or underhand (let’s leave that to the casinos, shall we) but a lack of corporate inertia and an ability to tackle customers on an individual basis gave the brand a real edge when it came to making buyers happy. There’s also some evidence to support the theory that HDT under Brock did play a bit loose and fast with the rules that Holden otherwise might have had in mind. But beyond that, the HDT operation’s ability to change direction quickly, engineer things on the fly and respond to individual customer requests meant that it was quite unlike any other car-maker.

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The story starts with a young Peter Brock being talent-spotted by none other than Harry Firth who was then running the Holden Dealer Team whose aim was – and we’re not really over-simplifying it here – to win Bathurst. By 1979, Harry was off the scene and Brock had purchased the HDT race team. Immediately, PB could see the potential synergies in selling cars off the back of race-track success (hell, the big car-makers had been doing it for years) and by 1980, the first Brock Commodore was a reality and HDT Special Vehicles was born.

A pair of Brock Commodore prototypes was built in 1979, based on VB Commodores (although no production HDT car was ever a VB, the earliest being a VC) and at least one started life as a 4.2-litre car which was then fitted with a warmed-up five-litre, a TH350 auto (in place of the Trimatic) and an LSD. The bodykit fitted to the prototypes was pretty faithfully carried over to the production VCs (including the Irmscher wheels) with Bilstein shocks sharpening it up underneath.

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But right away, you could see how HDT did things differently. Where major manufacturers either warehouse prototypes or crush them, HDT actually used one of the two prototypes as transport for HDT staffer, the redoubtable John Harvey, and then consigned it to a Sydney Holden dealer where it was sold to a retail punter. In any case, the rev-heads of Australia loved the whole thing and Brock went on to build more than 4000 cars including VCs, VHs, VKs, VLs and even a handful of WB-Statesman and ute-based cars.

Another important difference between then and now is that many HDT models formed the basis of the race cars that would propel the Brock mystique even further. These days, a Holden V8 Supercar has less production car in it than a robot has stem cells. But back then, Group C (and later Group A) regulations which formed the premier category (and, crucially, the Bathurst race) required a road-going version of the race-car to be built in sufficient numbers for the model to be homologated to race. And that era is where HDT’s cars came in.

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Ultimately, the Brock-Commodore formula became a victim of its own success. That ability to tailor a car to exactly what the customer’s wallet would cope with was, in the end, what killed off the whole thing, sending Brock into the business of modifying Ladas and leading Holden to establish HSV to cater to the same market (broadly speaking). There are some who say it never happened, but there are plenty more who know for a fact that you could order your Brock car with plenty of special bits and pieces including amped-up power outputs and special suspension or brake hardware. On the surface, this was a splendid business model; give the people what they want and make the till ring more loudly in the process. In reality, though, it was unsustainable thanks to Holden’s corporate jitters.

You see, the HDT cars were still being sold through Holden dealerships and carried a Holden warranty. Which was fine by Holden as long as Brock was sticking to the specification-script. But within Holden, there were plenty of nerves at what was seen as Brock supplying off-the-chart one-offs to selected customers which may or, more seriously, may not have complied with all the mandatory government regulations as regards emissions etcetera, as well as General Motors’ own internal requirements for durability and testing.

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I know for a fact there was huge variation between HDT cars. As a young journo, I’d sometimes be sent down to Port Melbourne to pick up whatever Brock car we were testing, usually to be handed the keys by PB himself (no small event for a young fella who cut his teeth on Bathurst races). And I can tell you that some of the VKs and VLs we tested were definitely sharper than others, some had obviously heavy-duty clutches and who knows what else was going on.

Brock, meanwhile, was having none of Holden’s finger-wagging and continued to give the public what it wanted. But he pushed things too far when he invented the Energy Polarizer, refused to add his signature to HDT Commodores ordered without the little box of resin and wires and then stuck two fingers up at Holden by releasing the VL Director complete with an independent rear suspension that Holden had not been able to test or verify for itself. Holden, of course, pushed back and the whole thing came a-tumbling down. Publicly, it was all about the Polarizer. Privately, Holden’s concerns were much broader. Had Brock toed the corporate line, of course, things would have been different. But then, that would have meant that the Brock Commodores we know and love might have been very different beasts, too.

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