Project Greetham : Hillman Imp Track Car
The passage of time has served to obscure the significant role played by small, family run automotive tuning firms, the kind which had their heyday in the ’50s, ’60s and ’70s. It was an era when working on and tuning your own car wasn’t so much a hobby as a Sunday afternoon ritual, with garages the length and breadth of the land more than happy to attempt to coax extra performance from your common or garden model, for a fee of course. Many of these firms specialised in one particular kind of car or type of engine, and for much of the period old school tuning was very much the order of the day; think ported and polished heads with enlarged valves, free-flowing manifolds, chunky cams and big, throaty twin DCOE setups.
One example of classic tuning from a small company utterly dedicated to a specific model was Greetham Engineering, a small, Chesterfield based concern dedicated to wringing extra performance from the Imp. Greetham Imps might have never attained the levels of popularity associated with comparable companies dedicated to rival offerings from Ford or BMC, but they their work was undoubtedly effective and retains a cult following to this day.
The Imp’s shell was hiding a number of rot spots, all of which were cut out and replaced with fresh metal
The above was at the forefront of our mind when we were commissioned to undertake a restoration and light restomod on one of the few surviving Greetham Engineering Imps, the freshly prepared shell having been dropped off at Retropower in 2017. The owner, a serial Imp fan, requested that the finished car be enjoyable both to drive and to look at, something reflected in its intended use – part time track day toy, part time living room ornament.
We were initially under the impression that it was ready for print and that it would be a swift restoration, however closer inspection revealed the shell to be in need of attention. There were the usual areas of concern, the kind you come to expect when running a business charged with the recommissioning and restoration of classic cars, but also plenty of evidence that the Imp had a lead a hard, or if you were feeling charitable, storied, life. Getting the Hillman’s full complement of panels to fit in the correct manner took an extended realignment process, with the doors proving especially troublesome.
The Imp received a great deal of custom work before being sent for paint
The owner’s intention to use the car on track dictated much of the custom work required, with a need to add in as much strength as possible a primary concern. The custom cross-mount running the length of the engine bay and attaching to both the motor and the rear bulkhead is one example of this, the corresponding interior cross bar another. The latter (now hidden by custom aluminium panels and mounted alongside the battery and fuel system) used as a harness mount another. These two braces effectively sandwich the rear bulkhead and imbue the bodyshell with some much needed rigidity.
The rear off the Imp including bracing bar and the uprated fuel system
Re-engineered suspension was always going to be a central aspect of the Imp project
The Imp’s suspension received considerable attention, again as a means of further polishing its on-track abilities. New rear swing arms were fabricated from scratch, with eccentric bushes for camber and toes adjustment and coilovers for ride height tweaks. The entire rear assembly is connected to the interior cross-bar and is therefore securely linked to the bodyshell. It’s a similar story at the front, where you’ll now find modified wishbones with kingpins and eccentric bushes for camber and toe adjustment, with billet alloy brackets (for reduced weight and enhanced appearance) and height adjustable coilovers.
Custom offset Revolutions and an incredibly high spec Imp engine – our kind of jigsaw puzzle, basically
The colour now on the Imp is actually a current Vauxhall shade called ‘Sunny Melon,’ an eye-catching hue more commonly spotted on Corsa Ds, albeit one we felt worked well with the Imp’s straight-edged styling. Other exterior changes are a little less apparent, the bonnet vent, remodelled bumpers and custom, plasma-cut grille but three examples.
The freshly built Imp engine and its custom brace
The engine, a water cooled ‘four’ slung out the back, has always been one of the Imp’s defining features so there was never any question of either replacing or relocating it. More importantly from our point of view, the owner had stressed his desire to take to the track in the finished car and had made preparations accordingly. Said preparations manifested themselves in the highly specialised, Rodwell Motorsport built Imp engine dropped at Retropower midway through the build, the spec of which now reads like a like a list of dream ‘go faster’ Imp parts.
The 1200cc motor is based upon a Sunbeam block that’s been machined to house extended wet liners ands a dowelled alloy spacer plate, with a large capacity baffled sump and a block strengthening kit. You’ll now find a quartet of cast, 74mm pistons with NPR rings and billet con-rods nestled in said block, plus a 70mm billet crankshaft.
Rodwell Motorsport built Imp engine should rev all the way to 8200rpm
It’s a similar story ‘up top,’ where you’ll now find a Sport head with Wills Rings, tapered inlet ports, 25mm exhaust ports, multi angled valve seats blended into enlarged throats and reshaped combustion chambers. Maintaining the old school tuning theme, the head also boasts bronze valve guides, enlarged valves, completion springs with Titanium collars and a GE3 race-spec cam, complete with a fully adjustable sprocket and lightweight tappets.
The Greetham Imp is slowly coming together and should be up and running by the end of the year
Few single parts can make as big a difference to a car’s overall appearance as a set of wheels, and we were at pains to pick a set which suited the Imp and its motorsport origins. Four-spoke Revolutions were therefore something of a no-brainer, though getting them to work with the four-pot Wilwood calipers and swing-arms required some creative thinking.
There’s a yellow, black and blue colour theme running throughout this build, though it will be at its most obvious when peeking inside, particularly as there will be no carpet. The dash will eventually get a one-off instrument panel housing all clocks and dials, a product being made for us by Speedhut in the USA, while we’re planning re-purposing many of the recesses and holes to run an aftermarket instrument panel (right) and electronic water pump display (left). The seats are Motordrive, while much of the interior will be clothed in either black leather or black Alcantara and with various ‘Greetham Engineering’ logos dotted about.
