Holden HK

Introduction

The HK Holden was the most influential Holden model to date, bringing a large array of options and mechanical features - most importantly of which was the imported Chev V8 engine. Another important milestone for Holden was the introduction of the now infamous 'Kingswood' name for the volume selling model.

The new HK Holden was bigger, lower and heavier than the previous model, and boasted two major model additions to the range. For the first time there was a Holden luxury vehicle, the 'Brougham', and a sports coupe, the 'Monaro'. Most important for these two new models was the V8 engine, although it could be specified as an option across the entire HK range.

The base model HK sedan was the 'Belmont', while the formally known 'Special' was now to be known as the 'Kingswood'. The up market 'Premier' was retained (and featured a different roofline to the lesser models) and in July 1968, the extended version of the HK sedan, the Brougham, was released. It was over 20cm longer than the Premier and featured as standard the Chev 307c.i V8 engine, Powerglide auto transmission, power steering and the most plush Holden interior to date.

In July of 1968 Holden introduced the Monaro sports coupe to the HK range. Based on the sedan, the pillarless Monaro was the first local vehicle of its type and won Holden a legion of new fans. The three Monaro models included the potent 'Bathurst-Bred' GTS 327, fitted with the US-built Chevrolet 5.3 litre V8 engine. With the HK, Holden offered a larger choice of models, engines, transmissions and options than had previously been seen in a massed-produced Australian car. Safety features fitted to all models included an energy-absorbing steering column (another Australian first) and dual circuit braking system.

More Options Than Ever Before

The HK Holden was available in more configurations than any previous model. There were six-cylinder and V8 engines, optional air-conditioning, bench and bucket seats, drum and disc brakes, and any number of Nasco accessories. But more important than the options list was the way it handled, and the HK handled very well, no longer the kneeling, wallowing, swaying car that the HD-HR series had become. The two outstanding points in the HK were the handling and the good, ultra-quiet ride on all surfaces.

When released, many considered the styling a little bland, others thought it looked a little too much like the Falcon, while others thought it borrowed too much from the Chevy II Nova. Regardless of what some thought, however, the Australian buying public liked what they saw, and headed down to their Holden dealership to place an order. When they arrived, they had three models to choose from - Belmont (Standard), Kingswood (Special) and Premier, the Premier being identified by four headlights, an egg-crate grille and squared-off roofline. The engines - 161, 186, 186-S and 307 cu in. V8 – were available through the range, along with most of the sweeping list of options. However, compulsory with the V8 (at release) was the automatic transmission and limited slip differential, while air-conditioning was available only with the V8.

The HK was longer, wider, lower and heavier, but with increased ground clearance, due mainly to a rise in wheel size from 13 in. to 14 in. The Belmont with 161 quickly came to be considered as the “Poverty Pack”, seeing the Kingswood with 186 become the favoured family sedan configuration. In this guise it also proved to be the best value and the best all-rounder. All the models represented a step forward in safety design, mainly the telescoping steering column, knock-out mirror, flexible knobs, shrouded door handles and dual circuit brake system. You would be reminded of the extra safety fitted to the HK each time you drove it, as the seat belts were fiddly to adjust. Another problem on early versions was with the exterior rear vision mirror, which could be thrown out of adjustment way too easily, including by wind pressure alone.

The 120 MPH Holden

For A$600 you could option the 210 bhp and 307 cu.in., that included an incredibly high gear 2.78 final drive. The high gearing was thought by many to be Holden’s attempt to have the V8 put in fuel consumption figures similar to that of the sixes. The high final drive ratio and tyre combination was common-enough engineering on American cars (although 2.7 was virtually the tallest final drive ratio available there) and there were some equivalent cars using 6.91-14 tyres with 2.7 final drives, such as Plymouth's Barracuda with the 318-inch engine, the US Falcon with 289 V8 and the Mercury Montego with 302 inches (albeit with 7.35 tyres). However, it was generally accepted that in Australia you geared a car to favour acceleration between 40 and 60 mph because of the limited overtaking space on atrocious main highways.

The Holden's 307-inch engine was in its sweet spot over 55 mph (near 2000 rpm, or just under the peak torque figure of 2400rpm). Around town the tall final drive made a lazy engine even more lazy – but at least in theory it should have been a little more economical. Holden claimed 22 mpg, but we have heard few that managed to achieve anywhere near that figure. Closer to the truth was a consumption figure of around 18 mpg, which was better than the lower-geared Falcon and Valiant V8s. However, in all the V8 and six-cylinder cars there was annoying exhaust and drive line resonance and vibration periods; at odd speeds the HK could buzz and rattle. Holden marketed the HK as one of the tautest and quietest they had ever built, and that was true – so the annoying buzz was not as a result of some issue with the body itself, rather the engineers must have had difficulty getting rid of the resonances. They were particularly obvious in the V8, which was not a smooth engine.

Both the Six and V8 were very quiet, however, and it was this and the quiet ride that allowed Holden owners to discover noises they had previously never heard. One was rumble from the crown wheel and pinion assembly. Holden’s always had the noise, but you were rarely able to hear it until the HK came along. Another noise was a squeal in the automatic transmission, which manifested itself as a sort of whine in Park and Neutral positions and distinct roughness when accelerating mildly away in Low.

Both the drum and disc brake systems did their jobs well. The HK had delightful light pedal pressure, even on the non-assisted drum brakes. With dual hydraulics, pedal pressures were inevitably high, but on the Holden they were not even as heavy as the Valiant's servo dual-system. The servo-assisted Holden discs produced a pedal height that was much closer to the floor and thus in better relationship with the other pedals, but the servo was, to the minds of most road testers of the time, still far too sensitive. On the other hand, the drums would produce marked fade and a steep rise in pedal pressures, together with unpredictable (but slight) pulling, after six to eight 0.5G stops from 70 mph, however they recovered quickly. GM-H was particularly sensitive to criticism of its drums at the time (on the HK these had increased to 138.6 sq ins. of area) – most believed quite rightly that they should have been a thing of the past and never fitted even to a “poverty pack”, particularly given the increased safety measures Holden had built into the car.

Today we can look back on the 4 wheel drums on the HK and call them “adequate” - except the (temporarily) compulsory drum system on the V8 with air-conditioning – which really never should have hit the showroom floor. The biggest surprise on the HK was the handling. Holden engineers set about creating a better driving position, lowering the steering wheel and shrinking it by half an inch. And by creating a good driving position, a car will “feel” like it handles better without any alteration to the suspension. But the increase in wheel-base and track, the lower roll couples made possible by lower-profile tyres and better weight distribution and the gearing-down of the steering, made the HK exceptionally stable. Don’t be fooled by what any Ford or Valiant aficionado will tell you, at the time the HK was the best handler of the "Big Three" without question.

On loose, wet and grass surfaces you could get the HK into the most incredible attitudes. It was easy to spin deliberately in its own length on wet bitumen; on grass you could get it three-quarters of the way around (through 135 of the 180 degrees) and still get it back into line again; on loose dirt and gravel it was superb except for a slight tendency to over-correct on opposite lock due to the low gearing of the steering. The wheel actually took five turns lock to lock, but all the way it was smooth, accurate, completely devoid of road shock, yet transmitted a lot of road information. The HK's roll angles were slighter, and with the six-cylinder engines had noticeably less understeer. It could be made to oversteer with power - something that made no difference in the HR unless you optioned the limited slip rear end. The V8 made the HK understeer markedly, and with the high gearing we mentioned before, there was hardly enough power on tap low down to balance out the understeer by the throttle. The ride was excellent on all surfaces, with only slight reflected radial ply thump and a lot less underbody noise on gravel than the HR model.

Inside the HK

Unfortunately the standard bench seat was little improved over what was offered in the HR - still thin in spots and hard in others. The reclining buckets, however, were superb. They gave very good grip around the hips and shoulders and good reach up to behind the knees. The bucket-equipped Kingswood was by far the nicest car of the range to drive. The new trim fabrics and designs were pleasant enough, and the dash layout was adequate, if smacking too much of 1961 Chevrolet Bel Air and lacking in real character. But at least everything was where the driver could reach it, and finally there was a Holden equipped with an air vent control that delivered sufficient fresh air. The horn was operated by a flat polypropylene strip across the two wheel spokes. The seat belts required individual - and very awkward - adjustment on both sash and lap straps and were not as comfortable to wear as most. Another poor interior design point was that the big central ashtray was prone to also act as an extractor airstream from open quarter vents. However, the heater/ demister controls were sensibly placed in the dash centre.

Leg room front and rear was excellent, the relationship of door hardware to legs was good, the handbrake in its new spot on the left could actually lock the rear wheels if you pulled hard enough and the two-position door stops were a great idea. The car was easy to enter and leave, the doors sweeping out over low floor sills. It was also reasonably simple to wash, with a minimum of exterior bright-work and a lot of the HR's sharp, knuckle-splitting sheet metal edges removed. The air-conditioning was hailed as a miracle during summer by all those lucky enough to have one fitted, but even though it used ozone depleting CFCs (to our mind CFC aircon always worked better) it was not powerful enough at idle on really hot days.

But if things got hot inside the cabin, spare a thought for your groceries in the boot. The rear expansion box in the exhaust line was mounted transversely under the boot floor, and as a result, the boot floor got very hot. Road testers of the time were left wondering how the engineers had missed this, as almost everywhere else the HK showed evidence of careful thought. But, on a more positive note, at least the boot was big, despite a welcome increase to 16 gallons in fuel tank capacity.