Hillman Imp

Introduction

The Hillman Imp was the first mass-produced British car to have the engine in the back, and the first to use a light aluminium alloy die-cast engine.

Slanting sharply from left to right to lower the centre of gravity (and leave room on top for luggage), the single overhead camshaft design had an unusually high compression ratio of 10 to 1.

The first car to use a Diaphragm Spring Clutch, it also featured many standard inclusions that would not become common on other vehicles until much later.

The list included a third rear hinged 'door' (hatch), a special folding bench seat in the back, automatic choke, no grease points, gauges for temperature, voltage and oil pressure.

The engine drove forward to the gearbox, then back through an orthodox differential to independently sprung rear wheels.

Delivering 39 bhp at 5000 rpm, the Imp was good for a top speed of around 80mph (126 km/h). Sitting on 12in. wheels, it had smart but hardly spectacular styling - similar to the Corvair fashion.

It had good all-round visibility with easy to read instrumentation (set inside two same-size dials for speedometer and auxiliary gauges). Trim was simple but practical in the Rootes tradition, but the Imp was one of the few British saloons to have a heater as standard equipment.

Providing an efficient heating system was cleverly developed by the engineers, their devising a system whereby heated water was passed up to the front luggage space via the left hand sill and returned by the right hand sill to the engine bay.

In the luggage bay the water went to a conventional heater fan unit located in either the space beneath the right-hand headlight to that side of the air intake box or to an internal heater on the internal bulkhead with air coming through a fan mounted in the area below the headlight. It is a shame then that the heater was standard on only some models, and most Australian versions were not fitted with heaters.