Holden HDT Problems

When Peter Brock started his special vehicles operation in 1980 he could not have envisaged its impact on the local car business 25 years later.  Brock admits he used the Shelby Mustang operation in the US and AMG in Germany as models for his HDT Special Vehicles, which in turn provided the model for Holden Special Vehicles and Ford Performance Vehicles that have followed and flourished.The first special was the VC HDT Commodore, released in 1980 to much fanfare. As the first of the genre it's now a classic appreciating in value.Model watchAs with the operations he emulated, Brock's brief was simple. He'd take a stock VC Commodore and modify it to enhance its performance and road-holding without compromising ADR compliance.He chose the top of the range VC Commodore SL/E which already came with plenty of fruit, the perfect base for Brock to build a European-style high-performance sports sedan that was comfortable, but handled well and looked sexy.It came already fitted with Holden's 308 cubic inch (5.05 litres) V8, but Brock and his team blueprinted it and fitted big valves which bettered standard V8 performance.  They also fitted a heavy-duty air-cleaner taken from a Chevy and added a fresh air intake to improve its breathing. It was fitted with the Holden factory dual exhaust system.With Brock's mods on board the Holden V8 put out 160kW at 4500 revs and 450Nm at 2800 revs which had it racing to 100km/h in 8.4 seconds and through the standing 400m sprint in 16.1 secs.  Brock offered the choice of Holden's four-speed manual gearbox or the three-speed auto, and a limited-slip diff was standard.Underneath Brock really worked his magic, fitting uprated and lowered springs and Bilstein gas shock absorbers for a lower stance and much-improved handling.  German Irmscher 15-inch alloy wheels and Uniroyal 60-series tyres completed the grip-and-go picture.A sporting car needs a sporty image and Brock gave it a major cosmetic makeover in the form of a fibreglass body kit with wheel arch flares, front bib spoiler and a rear wing.  Colours were white, back and red, and the package was finished off with some wild red, black and white race stripes down the side.Inside Brock enhanced the SL/E interior with a signed Momo steering wheel, a special gearshift knob, and a driver's foot rest.  Doesn't sound so special today, but in 1980 there was nothing like it.He built 500 VC HDT Commodores. He probably didn't feel it would last but his HDT specials were a sensation, continuing until 1987.  Today HSV builds special Holdens, FPV does Fords. It's unlikely either would exist if Brock hadn't needed funding for his race team.In the shopWhen considering a VC HDT Commodore it's important to remember that the foundations are strictly Holden so the main mechanical components are relatively easy to find to replace, and easy to repair or service.  Check that the special Brock components are there, the signed steering wheel, Irmscher alloys, high-flow air-cleaner.When Brock built those VCs, body kits were rough and ready. Unlike today's body kits, made of durable material to take a knock and fit well, the old kits were fibreglass, didn't stand up well when hit, and didn't fit well.  Check body kit components, such as the wheel arch flares, for cracking around attachment points and distortion between the mounting points.Crunch timeDon't expect airbags in a VC Commodore, they weren't fitted. ABS wasn't an option, but it did have four-wheel discs and rack-and-pinion steering, and the road-holding of the Brock-tuned suspension.VC HDT BROCK COMMODORE 1980Rumbling V8 exhaust notePresence of special Brock partsHigh fuel consumptionSolid performanceComfortable rideReassuring handlingPotential to increase in valueRating15/20 Good looking classic Australian sports sedan with Brock branding that has the potential to increase in value.

Peter Brock’s name will always be synonymous with Holden. The late great driver forged his relationship with Holden with a string of sensational race victories in the 1970s and will forever be remembered as a Holden hero. Never was the bond between Brock and Holden stronger than it was in the early 1980s when Brock set up his own car company and produced a series of race-bred road cars based on the Holden Commodore. There were many great HDT-branded Commodores, but one of the greatest was the ‘Bluey’, the born-to-race Group A Commodore built for the new international Group A racing rules in 1985.MODEL WATCH In 1985 Australia’s touring car racing changed from the home-grown rules that has been in place since the early 1970s to a new formula devised in Europe. The local rules had moved touring car racing away from the street by allowing manufacturers wide ranging freedoms to modify their production cars to suit the track, but the new overseas rules were more restrictive and they reintroduced the requirement to build at least a limited run of production cars to qualify for racing.The VK SS Group A was the first of these so-called ‘homologation’ specials Holden built during the Group A era. It was based on Brock’s HDT SS Commodore, which itself was based on the Commodore SL, the lightest model in the Holden range. All were painted ‘Formula Blue’, hence the nick-name ‘Bluey’ by Brock enthusiasts, and featured a Brock-inspired ‘letter box’ grille and a body kit derived largely from Brock’s previous Commodore racers.Inside it had special blue trim, full instrumentation and a Mono leather steering wheel.Underneath the Group A had a similar suspension set-up to that on Brock’s SS Group Three, with Bilstein gas struts and shocks, and SS springs. Like the regular SS it had a 14 mm rear anti-roll bar, but there was a much heftier 27 mm bar at the front.Brakes were lifted from the Brock SS Group Three, while the wheels were HDT’s 16x7-inch alloys and they were wrapped in Bridgestone Potenza 225/50 rubber.Under the bonnet sat a specially tweaked 4.9-litre Holden V8. Under the Group A rules the Commodore would have been heavily penalised with extra weight had it raced with a regular-sized Holden V8, so the engine’s capacity was reduced from 5.044 litres to 4.987 litres by reducing the stroke to squeak in under the 5.0-litre limit.The rest of the engine drew heavily on Holden’s past racing experience, and included cylinder heads modified by engine guru Ron Harrop, heavier L34 conrods, heavier Chev/L34 valve springs, Crane roller rockers, a lumpy Crane camshaft, Rochester four-barrel carb, matched inlet and exhaust ports, double-row timing chain, lightened flywheel, HM headers, and Lukey mufflers.All up it produced 196 kW at 5200 revs and 418 Nm at 3600 revs, an increase of 19 kW over the regular Holden V8 with equal torque. It was also a more free-revving engine and Holden lifted the red-line by 1000 revs from the standard engine’s limit of 5000 revs. Backing up to the new engine was a stock Holden M21 four-speed manual gearbox.Tested at the time the VK Group A would reach 100 km/h in around seven seconds, and cover the standing 400-metre sprint in 15s. It was quick for its time, handled and stopped exceptionally well, and looked great with an unmistakable Brock road presence.Under the Group A rules Holden had to produce 500 cars before they could race it. These were built on the Holden production line and then shipped to Brock’s factory in Port Melbourne where it was completed.IN THE SHOP Under the Brock skin it’s a Holden Commodore and subject to the same issues that afflict regular Commodores. Under the bonnet look for oil leaks around the engine and power steering. Inside look for wear on the light blue trim as it doesn’t wear well, and check the dash pad for cracks and distortions through exposure to the sun. The good news is that most owners treasure their cars and look after them accordingly. The most important thing is to make sure it’s a genuine Group A model and not a fake.IN A CRASH Safety was in its infancy when the VK Group A was launched, so it lacked the systems now taken for granted. There were no airbags, or ABS, and stability control was still years away from reality. In 1985 cars mostly fell back on body strength and crumple zones, while drivers had to rely on seat belts in a crash. But the VK Group A did have quite good, at least for the time, active safety with its responsive handling and good-sized disc brakes.AT THE PUMP With a highly-tuned V8 under the bonnet the VK Group A is never going to be a fuel-miser, but fuel economy is something few owners would care about. The VK Group A is a sunny Sunday car, it’s not likely to be driven daily, so fuel consumption is of a lesser concern to those who own it. It requires a high-octane fuel, and unless it’s been modified for unleaded it requires an additive. Expect to see economy figures of 15-17 L/100 km, but it depends on driving style.LOOK FOR • Classic Aussie muscle• Brock cred.• Authenticity• V8 performance• Responsive handlingTHE BOTTOM LINE A great Aussie classic muscle car built by a true legend of motorsport.RATING 85/100