Star of the 1966 Motor Show, the Interceptor-based Jensen FF represented one of the first successful attempts to produce a four-wheel-drive passenger car. 'FF' stood for 'Ferguson Formula', a four-wheel drive system developed by the Harry Ferguson Research Company, which was also responsible for adapting the FF's Dunlop Maxaret anti-lock braking system for automotive use. The FF debuted alongside the new Interceptor and both models used the same basic chassis, running gear and 6,276cc Chrysler V8 engine inherited from the preceding C-V8. With 325bhp (SAE) and 425lb/ft of torque on tap, performance was more than adequate, The Motor recording a top speed of 140mph with 100mph arriving in 19 seconds. Leather upholstery, reclining front seats and walnut veneer were all standard features, while automatic transmission was the choice of almost all buyers (it was the only option for the FF). Mechanical changes to the FF kept abreast of those made to the Interceptor, but although the two models looked indistinguishable from a distance there were numerous subtle differences, the most obvious being the FF's twin side vents.
Priced at 30% above the Interceptor, itself not a cheap car, the FF was the privilege of a wealthy few and when production ceased in 1972 only 302 had been made, 193 of which were to 'MkI' specification like that offered here. This FF was sold new via Charles Follett Ltd of Mayfair, London and first owned by one William Birtwistle of Allied Mills in Blackburn, Lancashire (a copy of Jensen Motors' original invoice is on file). Previously registered 'WGP 17G', the car was purchased by the vendor in 1975 and used until a full restoration commenced in 1985. This involved a bare metal restoration of all sheet metal, the bodywork being lead filled and repainted in the original Regal Red colour. All mechanicals were serviced and overhauled, a MkII engine installed, and a new petrol tank fitted, all of which was done in 1985 by Sturdy & Lowe of Grimesthorpe (mostly ex-Jensen staff). Very little used over the next year, the FF was reregistered in 1988 before being waxed and dry stored. Areas still requiring attention include the original beige leather interior, which is worn and needs re-trimming; the bumper bars, which need re-plating; and the power steering, which needs new seals. The original MkI engine is available to the buyer but has a cracked cylinder block. Sold strictly as viewed, 'SJN 421G' is offered with its original and continuation old-style logbooks, 'Statement of Origin' from factory records, sundry restoration invoices and Swansea V5 registration document.