When the HD was released in February, 1965 Holden loudly proclaimed it was a “Leap Ahead”.
There was a new high-performance engine, the 140bhp X2 and the styling ensured it was one of GM’s most advanced designs of the era.
The lines were sharp and crisp and the blade-like front fenders were firmly aimed into the future.
The HD’s radically curved doors and side windows had only just been introduced on GM’s full-sized cars that same year.
They added a full five inches/127mm of interior width but only two inches/52mm of exterior width.
Holden’s product planners recognised that Australian families and baby boomer teenagers needed more space and elbow room.
Trouble was, the HD’s packaging benefits were compromised by the cost driven re-use of the narrow EH chassis, poor brakes, carry over engines, marginal handling and an insistence by engineers of an SUV-like nine-inche ride height.
The outcome was a car that was tall, looked tippy-toed, under-powered (except for the X2) and under-braked.
After a strong first few months, sales declined and it was replaced by the HR in April, 1966.
So, where did it all go wrong?
The genesis of the HD’s styling was a secret GM concept car, the Solaris.
You can read about the Solaris in a previous column.
Solaris was developed by Carl Renner, Don Lasky and Leo Pruneau in 1961.
It was an ideas car which enabled GM’s executives to visualise and consider a number of styling concepts.
When work on the Solaris finished Don and Leo were given the tasks of styling the 1964 Opel Kapitan and the HD Holden.
Leo, who would become Holden’s design director, remembers the design parameters he was given for the HD.
“Holden wanted to sit three full-size adults across the front and rear seats,” he said.
“At the same time they wanted nine inches/229mm ground clearance.
“They also wanted to stand the spare tyre upright in the boot and wanted all of this to fit on a wheelbase of 106 inches/2692mm.”
The bean counters demanded the HD retain the existing EH track to save costs.
Leo says that to achieve this package the solution was to use the Solaris as a template and “go long, go wide and go up.”
The body was raised off the floor by an inch/25mm so that the floor could be flattened to reduce the intrusion of the transmission tunnel and free up legroom.
Curved side glass and doors added to interior space.
The engine was moved forward three inches/76mm, also increasing the space in the cabin.
But that did nothing for handling and braking.
Taller and longer rear fenders accommodated the stand-up spare tyre.
This, in turn, influenced the height of the front fenders.
Although Detroit was developing the styling, Holden executives were not sitting back.
They sent their Chief Body Engineer, Reg Hall, to watch the clay prototypes of the HD take shape.
Reg had strong opinions and was not afraid to voice them.
Leo explains what happened.
“Originally Don and I had the car with flatter front fenders but Bill Mitchell, GM’s design boss, thought the car looked too short, so he told us to make the fenders jut out ahead of the grille. That’s when Reg arrived from Australia.”
“Well, Reg took one look at them and protested that it would be too hard to manufacture and told us cut them back. So, we did what he asked.
“Then, Mitchell ordered us to lengthen them again. And then Reg asked us to shorten them. This argument went on and on during April and May, 1962.
“Of course, Mitchell was always going to get what he wanted because he was the boss. He convinced Holden’s management and that’s the way the car went into the showrooms.”
History has not been kind to the HD.
It was heavier than the EH.
The carry over 149 and 179 engines struggled under the HD’s additional weight.
Fuel consumption increased.
The drum brakes were not adequate.
Moving the engine forward made the handling worse.
The front fender blades were criticised as being a potential danger to pedestrians.
Despite its controversial exterior, the HD’s interior design has never been questioned.
The increased interior space was immediately obvious when compared to the narrower Falcon and Valiant.
But, buyers instinctively knew the car was less than it should have been.
The tippy-toed appearance summed up all the inadequacies.
The wide-bodied potential went unrealised until the HR arrived in April, 1966, with revised styling, bigger brakes and more powerful engines.
David Burrell is the editor of retroautos
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