Holden Monaro Convertible: The Australian Mercedes-Benz SL that is almost

When Holden pulled out of Australia in 2017, several prototypes, design sketches and story lines have surfaced.

That includes the story of what will become Holden Monaro Convertible. Not Marilyn, the Monaro-based convertible built for the 2004 Melbourne auto show, but the original car based on a VN Commodore car.

A phone call about a particular Monaro Convertible piqued my interest. It was an injured car in the hands of a former senior technician, before being sold to a friend of mine.

Not only were we behind the wheel of the car, it also came with comprehensive documentation showing the design, engineering and marketing process that Holden and HSV are planning to follow in their efforts to bring the car to production. export.

While our main focus here is on new cars, this story is too good to be hidden.

History

When it comes to producing a new car model, automakers need a well-thought-out business plan to ensure that it makes sense and ultimately turns a profit for them.

In the late 1980s, Holden Special Vehicle (HSV) was a new player on the block. Founded in 1987 by the late UK race car driver Tom Walkinshaw, the brand’s specialty is in taking Holden products and enhancing their performance.

The late 80s were all about more power and robust design. In 1989, HSV produced its first car: the VL Commodore SS Group A SV.

It is badged Holden and created with similar racing purposes in mind.

Then HSV rolled out the VL-based SV88 and a pair of six-cylinder Commodores. It wasn’t until the generation change to VN that HSV got serious about amending the Goods.

That’s where this story begins.

How was the Monaro Convertible born?

Remember the engine program? Australia has two major shows held every year – one in Melbourne and one in Sydney. This is a great opportunity for automakers (especially domestic automakers) to gauge interest in concept cars before they go into production.

HSV wanted to show off a high-performance four-seat luxury convertible and wanted to use the 1989 Sydney auto show as a testing ground.

Essentially, the company has been working on the HSV SV5000 and the next version of its racing analogue, the VN Commodore SS Group A SV.

In March 1989, HSV came up with the concept of a luxury convertible Commodore with the idea ready to enter the European fray. That contest includes Mercedes-Benz SLin the SL500 guise there’s a naturally aspirated 5.0 liter V8 making 235kW

The business plan includes a prototype that will be assembled in time for the Sydney auto show to gauge public reaction.

The prototype will be based on the Commodore Berlina (midsize specification) and will include a device running the HSV SV5000. That means swapping out the V6 powertrain in sponsor Berlina’s car for a larger, more powerful V8.

The V8 from the SV5000 features high compression pistons, a specific camshaft, an intake system, a header set and dual exhausts. It made an impression (at the time) 200kW of power, and is designed to be able to take it up to the SL500 from a performance standpoint.

Before the concept could progress any further, HSV commissioned a Melbourne design agency called KAF Creative to come up with an artist’s impression of the vehicle and support the business case. The design reveals a refined two-door convertible with a fabric roof.

In addition to the design, HSV also develops a business case that will be assigned to the management to launch the project. It proposes:

• A prototype built for the 1989 Sydney auto show
• 25 cars will be produced in the first year, which can be considered as a low-volume production vehicle.
• 100 cars will be produced in the second year, which will push it into the next compliance bracket and require more compliance work, along with crash testing
• Expected starting price is around 90,000 USD, or about 200,000 USD today

Engineers have been given the green light to invite Maverick Motors in Melbourne to design and build the conversion from a four-door sedan to a high-performance two-door convertible.

Maverick Motors quoted HSV $43,000 for the work needed to execute the prototype. With today’s money just under $100,000, that doesn’t seem like a bad value for the work involved.

Maverick Motors began the transformation in August 1989. It will always be difficult to meet the October deadline for the Sydney auto show, given how much work is involved.

October comes and goes, but the prototype is still incomplete. By the time it appeared in January 1990, HSV was officially dead. The project missed all of its major timelines, and the prototyping process showed that it would be too difficult to get the project to work as anything more than a single implementation.

Despite its challenges, HSV still wanted to complete the prototype. Maverick Motors kept it until March 1990, when the project was officially completed.

The changes are huge. Not only did Maverick cut the wheelbase, they also installed an independent rear suspension (not standard on the VN Berlina, but standard on the SV5000) at the rear of the second body, which is fused to the original. copy. They also swapped the engine and transmission, and made it all work with an aftermarket electric roof.

In total, the changes include:

• The wheelbase is shortened by 140mm and the front door is increased by 220mm
• Windshield lowered by 50mm for improved profile
• The side glass has been reworked to fit the new size
• The electric folding convertible was imported from Michigan and created by a company called Concept Cars
• The bodywork is painted in Maranello red

The vehicle was handed over to HSV for transport to the company’s headquarters in Notting Hill.

The following work was completed after it arrived:

• The V6 engine has been switched to the 5.0-liter V8 from the SV5000
• HSV adjustable springs and dampers
• The four-speed automatic GM TH700 has been switched to a four-speed adjustable SV5000 automatic GM 400
• The Momo steering wheel has been refitted and the interior trim has been updated to include the signature HSV . colors

What happened next?

I know what you’re thinking. Already VN, why is the car here VP?

After being completed in May 1990, it underwent an upgrade of its own.

The car receives 17-inch alloy wheels from VR Clubsport, front face from VN Group A and fender extensions. It was also switched from Maranello red to Heron white with Holden Racing Team (HRT) paint.

It was later used as an HRT and HSV promotional show in the parking lot at several Australian V8 touring motorsport events throughout 1993 and 1994.

Around this time, it is said to have been tested on the Calder motorway in Melbourne’s north by Bathurst 1000 winner and nine-time racing legend Peter Brock, who said it was “awesome, Let’s hope these go into production.”

In 1995 the car was retired and stored at HSV, where it lived until 2012. Since then it has been privately owned before being sold to a friend of mine.

What is it like to drive?

Our time behind the wheel was brief, but I own a 1993 Holden Commodore SS with HSV enhancements so being inside this car is a bit of an oddity – especially when it’s just new 1500 km on the clock. It becomes like brand new, and feels new throughout.

The roof’s action is electronic and there is a manual last latch mechanism to close it. It even comes with a canopy to hide the roof’s components when it falls down.

The shortening of the wheelbase means that second-row passengers have no legroom. Shoulder space is also taken away by the side of the roof structure, but rear-seat passengers got their own window switches for some hair in the face of wind.

Boot space is also reduced to accommodate the folding roof mechanism.

Oddly enough, when you look at the Monaro Convertible from afar, it actually looks like a drop-down plate. It cuts a slim line and an upgrade to VP specs actually rounds out the front edges of the car.

It still has the powerful V8 engine, which is synonymous with the Australian-made 5.0-litre V8.

Can this ever compete with the Mercedes-Benz SL500? Very unlikely. But it’s a shame it never gets its moment in the sun.

The next time Holden tried out a convertible was in 2004 with a Monaro-based Marilyn convertible.

No doubt Holden has faced similar challenges with making the numbers overlap, I think that’s a big shame!

What now?

The new owner hopes to put the car on display, to ensure that it remains a piece of Australian automotive history and is not hidden.

There’s a pile of one-time gems like this about where they’ll eventually spawn on the surface. Let’s hope we get to see the sequel soon.

I’m sure you’re all wondering, what’s it worth? With recent vintage Holden auctions seeing numbers over $1 million, this could be a classic attention span.

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