Like many other Rootes products including the Minx, the Super Minx was one of a badge-engineered series of models, sold under various marques.
The Singer marque was represented by the Singer Vogue which had been announced in July 1961, four months earlier than the Hillman Super Minx.[8] The range was joined in 1963 by a Humber: the Humber Sceptre.[9] The Singer Vogue and Humber Sceptre names would be retained by the successor Rootes Arrow model range. The Sceptre was developed as a four-door replacement for the Sunbeam Rapier, but was re-designated as a Humber shortly before launch, while the two-door Rapier based on the 'Audax' Minx continued unreplaced until 1967.[9] The Sceptre nevertheless was able to be successfully promoted as a more sporty car than the larger traditional Humbers.[9] Unlike the Hillman and Singer versions, the Super Minx-based Humber Sceptre retained the same roof, with large panoramic windscreen and shallow wrap-around rear window with fins, until the model was replaced, in the Humber's case in 1967, by a Hillman Hunter-based successor.
The cars differed in subtle ways, with the Singer being positioned slightly above the Hillman and gaining such extras as quad headlights, and the Humber topping the range, commensurate with Humber's traditional role as a producer of upmarket and luxury models. The styling of the Sceptre (as well as the Vogue) somewhat recalled previous, larger Humbers. The Sceptre marks 1 and 1A had a slightly different grille arrangement and front trim to the Vogue as well as a taller panoramic windscreen, sloping rear roofline and larger rear fins. It had been intended that the Sceptre be a sports saloon until shortly before its launch as a Humber, hence its sprightly performance compared with other Humber models.
Nearly five years after its launch, a Singer Vogue Series IV saloon tested by the Britain's Autocar magazine in August 1966, now with an advertised power output of 85 bhp, had a top speed of 93 mph and could accelerate from 0-60 mph in 25 seconds. An overall fuel consumption of 22.0 mpgimp was achieved. The test car was priced by Rootes in the UK at £911 including taxes, at a time when the Austin 1800 was retailing for £888 and the Ford Corsair GT was offered at £925. The performance was felt to be lively, and the gear change, supported on the test car with an optional overdrive, ‘crisp’ with well chosen ratios. Comfort and fittings were also commended, but the fuel consumption and the tendency of the heavy brakes to fade when used hard disappointed the testers: this would presumably not have been an issue had the road test been of a Humber Sceptre which had its stopping power from a servo-assisted 10 in front disc/rear drum arrangement.[10]
The Humber was also, at launch, fitted with a high tune version of the 1,592 cc and, from September 1965, 1,725 cc oversquare engine producing 80 hp and 85 hp respectively.[9] Early models with the 1,592 cc engine had twin single Zenith downdraught carburettors - later 1,592/1,725 cc engines used a Solex twin choke downdraught carburettor for simplicity. The twin Zenith carburettors had been hard to keep balanced. Other modifications included a water-jacketed inlet manifold, timing adjustments and stronger valve springs to eliminate valve bounce at high engine speeds. The later H120's 107 hp engine is a straight swap for both of these units and looks almost identical - it provides a useful boost in power to an already swift automobile. The unique Sceptre interior featured full instrumentation, including a tachometer marked up to 6,000 rpm, and a four-speed floor-mounted transmission with self-cancelling overdrive (with column-mounted control and indicator) on third and fourth gear for a total of six separate ratios in standard form. The lockout could be removed on first and second gears, and this was often done by Rootes in cars used for competitions such as rallying. In addition, the Sceptre was from the beginning provided with servo-assisted braking control and, unusually in 1963, 10-inch front disc-brakes. The Marks 1 and 1A were not available with an automatic option - although this was rectified with the Mark II cars, using a three-speed unit with automatic kick-down. This was a cheaper option than was usual at the time due to the deletion of the Laycock De Normanville overdrive fitted to the Manual cars.
There was a Singer variant of the smaller Minx as well (the Singer Gazelle) but no equivalent Humber version of the Minx, (except for the Humber 80 version of the Minx released in New Zealand, as is Humber 90 to the Super Minx in order to circumvent the government's maximum import number restrictions) which would have been uncharacteristically small for the Humber marque; conversely there was a sporty Sunbeam version of the Minx (the Sunbeam Rapier) but no Sunbeam version of the Super Minx.
In addition to assembling the Super Minx,[1] Rootes Australia produced variants of the Singer Vogue from 1963 to 1966 as the Humber Vogue and Humber Vogue Sports.[11]
At least six Humber Sceptre development mules were built with the same engine as the Sunbeam Tiger, a 289 cui Ford V8 unit. These never entered production, but at least one of the original cars survives.
