Vintage Thing No.130 - Marshall and Fraser Reliant Kitten Special Saloon

The Marshall and Fraser Reliant Kitten (Photo : Auto Performance)

While perusing old magazine articles about V8 Imps, this oddity turned up. It's a Special Saloon Reliant Kitten, which sounds so wrong but in practice went so well. The Marshall brothers had cut their teeth on Villiers powered karts and graduated to a Mini Traveller Special saloon featuring a monocoque chassis, tubular subframes and a full rollcage.

Beam axles at the rear are ideal lightweight substitutes for the rear subframe. (Photo : Auto Performance)

They developed the A series engine to its limit and not finding their power gains enough searched around for an alternative engine, soon deciding on the Imp. What Imps give away in capacity to A-series lumps they gain in screamability. Do not under-estimate the difficulties of fitting an Imp motor onto a transverse Mini gearbox. It involves a load of welding and machining. The Imp motor is longer and the crank sits deeper in the block. Somewhere I have a photo of an Imp engine in a Mini racer but I can't find it right now. (I did discover this device but that is by the by)

David Marshall is the engineer of the two brothers and he cut and shut and welded and hewed until they had a matched Imp and Mini powerplant. Unfortunately, by the time this car appeared in Auto Performance magazine back in August 1983, driver Ginger Marshall had suffered an errant rod that punched its way through the block.

So they picked up the pieces, made a wooden pattern and cast their own - just like that.

The engine didn't look like an imp any more. (Photo : Auto Performance)

David also used an Allen EN40 steel crank but kept Imp rods to create a bottom end good for 9400rpm. Turning their attention to the cylinder head they originally used a Greetham Imp head but subsequently re-designed it to use a toothed belt instead of a chain and drove the distributor off the end of it. Finding cam swaps and ignition timing  to still be a bit of a chore,  they re-designed the cam carrier further and began to develop a 1.2 litre engine in conjunction with renown Imp tuners like Ian Carter and Hartwell Engineering. a spin off project was a 1.2 litre Imp powered Mini hillclimber.

Dry sumping a Mini with its gearbox in sump sounds like a non-starter but David did it using a two-stage Pace pump dirven off the back the Imp water pump via a Renold  flexible chain coupling. Having gone to all that trouble, they found that warming the oil up took too long so they made a heat exchanger out of aluminium tubes. As the hot water cooled, it heated up the oil the normal thermostatic by-pass kicked in.

It said Reliant but didn't really look like one  (Photo : Auto Performance)

From their experience racing Minis they chose a steel pressure plate and flywheel especially modified to suit the imp crank.  This had a heavy-duty sintered-bronze plate driving through Jack Knight drop gears to a set of dog-type synchro gears, also by Jack Knight, and a Salisbury LSD. Despite dire warnings of catastrophe from those with bitter experience, they used the same driveshafts season after season but had just about become convinced - by the time of the Auto Performance article - that regular replacement would be a good idea. Wheels were a pair of 9 x 13inch Compmotive split-rims at the front with 8 x 13s at the rear shod with Avon covers. 

The driver rested on strategically placed pieces of foam within a cage mounted over the monocoque box sections. Front suspension actually incorporated much of the original Mini subframe as they realised that many people lowered the suspension too much and destroyed the geometry. The rear beam axle was located with radius arms and diagonal semi trailing arms and there were coil springs all round with Koni shocks. 

Braking was by 4-pot, AP racing calipers on 10.2inch ventilated discs at the front and, to achieve the right brake bias with the rear Minifin drums, two master cylinders are operated by the pedal through an adjustable balance bar.  This is despite and all up weight of 8cwt.

After campaigning with a Mini Traveller shell, they bought a Kitten bodyshell (that sounds so wrong to me as a cat lover), took some moulds off it before selling it, chopped them around and then produced some lightweight panels that clothed all the bespoke chassis fabrication.

 

There was more to both these cars than meets the eye. (Photo : Auto Performance)

Choosing a Reliant Kitten body shell - a light weight one of course - added to the whole joke and showed that although their intent was deadly serious, there was a delightful element of self-deprecating showmanship about the whole enterprise.