Automobile [Heron MJ1 Sport]
Maker and role
Heron Cars Limited, Designer
Summit Auto Manufacturers Ltd, Manufacturer
See full details
Model: MJ1 Sport
Manufacturer: Heron Developments Limited
Country of Manufacture: New Zealand
Construction: Unitary Fibreglass/Kevlar with Heron stainless steel patented fixing system, no steel chassis
Engine: Fiat 2 litre, 4-cylinder petrol, twin overhead cams
Output: 112 horse power at 5600 RPM,
Gearbox: Skoda 4 speed manual converted by Heron to 5 speed.
Suspension: Independent front and rear with coil springs/dampers.
Brakes: 254 mm discs front, 240 mm drums rear, unassisted.
Steering: Rack and pinion.
Wheels/Tyres: 175/70 SR 13 front, 205/70 SR 14 rear.
Weight: 720 kgs
Length: 3.9 metres
Width: 1.65 meters
The first Heron vehicle was a sports racing car completed in 1963 by Bob Gee and Ross Baker, founder of Heron Cars Limited (1962). After building one-off sports cars, Baker sought to commercially produce a road-going sports car, completing the drawings for the Heron MJ1 in 1979. The first prototype vehicle was completed in 1983 and went on show at the Auckland Motor Show the same year. As a result, 350 prospective buyers who had expressed interest at the Motor Show were asked to were asked to put down a deposit of $1000 to help with the production costs for the first cars. 30 MJ1 vehicles were subsequently ordered.
To make production commercially viable, Summit Auto Manufacturers Limited purchased shares in Heron Cars and established a manufacturing plant. However, the Board made the decision to add more expensive parts to the first-round of production vehicles and retail costs went up from the first advertised $16,000 to $27,000. This eventually saw Heron Cars placed into receivership by Baker, who had wanted to keep costs lower. MOTAT’s MJ1 is an example of what caused the rising production costs, in part due to the Fiat 2 litre engine, as opposed to the originally planned Skoda or Fiat 1600 engine. The imported Fiat 2 litre engines arrived, but required additional parts and meant some design changes which would add an additional $4000 per vehicle into production costs. The last Heron production car was completed in 1985.
MOTAT’s 1985 Heron MJ1 tells the story of technological development in production materials for the body and chassis of the vehicle. It is a two-seater coupe model with a monocoque design, which means the chassis is integral to the vehicle’s body rather than separate. The choice of fibreglass for unibody/monocoque emerged from Baker’s experience racing fibreglass boats and earlier use of fibreglass to develop an orchard spraying vehicle, the Spraymaster. It was picked for its durability, to overcome vehicle degradation issues, such as rusting. The choice of fibreglass for vehicle production was not new at this time, but other attempts had problems, such as mounting major components like the engine. The design for the MJ1 overcame this by having a steel roll bar to satisfy mounting requirements, and weak spots in the fibreglass were reinforced by Kevlar and/or steel mesh for structural integrity - a production method that was patented by Heron Cars.
MOTAT also holds MJ1 vehicle moulds, plans, pictorial, and a related manuscript collection, for this vehicle model.