By the early 1960s Jaguar faced a dilemma. Alongside its successful sportscar offering, namely the E-Type, its saloon range had become confused and commercially inefficient. The Mark II, the S-Type, the Mark X (or '420G'), the Daimler 250 and - as of 1966 - the 420, represented an unwieldy model range with all the associated tooling and production costs. William Lyons realised, from at least 1962, that a definitively new saloon with widespread appeal would be needed if the brand was to remain vibrant and able to produce an exquisitely styled and engineered car with an affordable price tag. Work began the following year on the new project, codenamed 'XJ4' - the XJ being a pseudoacronymn of 'Experimental Jaguar', the 4 simply a reference to the sequencing of this project relative to others undertaken by the Experimental Jaguar team.
The new car came to be known by the XJ6 moniker, all launch models having V6 engines as compared to the later XJ12 cars with V12 units. The majority of Series 1 XJs were equipped with the venerable 4.2 litre XK engines, a smaller proportion (MWK 28G included) receiving smaller-capacity 2.8 litre version of that engine. The ratio was approximately 3:1, with around 60,000 4.2 litre cars produced compared to roughly 20,000 2.8 litre variants. The 2.8 engine was created by shortening the stroke of the 4.2, primarily to appeal to the continental market where tax rules made the smaller capacity cars considerably cheaper. Unfortunately the modifications did little for the engine, which was only marginally more fuel efficient in 2.8 litre guise but which did suffer considerable drop in output (140hp compared to the 220hp of the original engine). Worse, after launch the 2.8 engines were to develop a reputation for unreliability as a proportion of cars required replacement engines having holed their pistons. It would later become clear that the piston crowns of the 2.8 litre cars were prone to coking with short, stop-start journeys. The design problems were attended to, but 2.8 litre cars - already relatively rare by virtue of the smaller production numbers - became rarer still with the passage of time, as their reputation put buyers off and given the attrition rate amongst existing cars.
The XJ6 would be the last Jaguar whose development William Lyons would personally oversee. It was the pinnacle of his career, as he attested to in one of his rare television interviews (speaking to Tony Bastable on Thames Television's Drive In in 1977). Sir William had both a keen eye for what was aesthetically appealing, and a parsimonious approach to developing and building cars which drove him to instil a 'right first time' approach to all aspects of the design and development process. This was an analogue, pre-CAD approach to design which engendered a flowing, organic beauty in the XJ. Development costs were indeed constrained by careful, methodical attention to each stage of the process and an appreciation across the company as to Sir William's disdain for wasteful use of resources. The late Norman Dewis - Jaguar's leading test driver and development engineer for three decades - reminisced about driving Sir William back to Browns Lane from his holiday house in Salcombe when the petrol warning light came on at Southam, some 20 miles from the factory: and Sir William insisting he coast home on vapours ('we don't need petrol Dewis!'), which he managed to do. The car ran out of fuel on passing the factory gates and Norman Dewis coasted in to the petrol pump with yards to spare.
The result was a desirable and unbelievably affordable car. The XJ came to be widely regarded as the most beautiful saloon car ever, inspirational for the generations of car designers who would follow. A 14-year old Ian Callum would later talk about how he was struck by its perfect proportions. The motoring journalists who reviewed it could not believe how competitive the list price was - around half the price of the equivalent Mercedes and BMW offerings. Retrospectively it is clear what a successful and important model the XJ proved to be, as a means of securing Jaguar's future.
By 1968 the design was effectively finalised. As the final step prior to mainline production, a team of apprentice development engineers were tasked with hand-building twenty 'development cars'. This was with a view to devising the most efficient sequence for mainline assembly, and for troubleshooting. Heynes, son of Jaguar's Chief Engineer Bill Heynes, was at that stage a 22 year old apprentice within the team - and was involved in working up chassis No.19 the car which, when registered, would become better known as MWK 28G.
As a development car, No.19 is non-standard in a number of subtle ways. The arrangement of cross-members and component within the engine bay is slightly different to the production cars that would follow; some parts (such as the aluminium door sills, hacksawed by hand) were evidently bespoked; and the reflector arrangement on the boot lid changed soon after production began (they were moved from an inboard position, flanking the boot lock, to sitting down below the lamp clusters). The most noticeable difference however is in the bonnet pressing.
Jaguar had intended the XJ to be launched in V-engine variants, but that was not feasible and instead it was launched with 2.8 and 4.2 versions of the 6-cylinder XK. The 2.8 engine had a shorter block, and could be accommodated under the shallow bonnet pressing that Jaguar had originally conceived with the flatter V12 engines in mind. However it was too shallow for the 4.2, meaning that the bonnet pressing had to be re-tooled. Production cars have a subtle but noticeably more pronounced hump in the middle of the bonnet, when seen alongside No.19.
Incredibly for a non-production car, and impossible nowadays, No.19 was later sold into private ownership in May 1970 having served almost 2 years with Jaguar's Press team and Test team. A replacement 2.8 litre engine was fitted in September 1969, in preparation for sale: not as a result of failure of the original engine, but because it was not judged appropriate to sell a vehicle with 20,000 test miles into private ownership. This, though, appears to have been the only concession - the car was sold to its first private owner with only a few hundred pounds discounted from the list price of a new car.
The response of the press and car-buying public to the newly-unveiled XJ was hugely enthusiastic. Waiting lists grew rapidly, perhaps one reason why No.19 commanded such a small discount from list price despite its gruelling first couple of years. Matters were not helped by the perennial labour disputes that plagued British industry at the time. At one point a strike at Wolverhampton Diecasting - manufacturers of brightwork such as the 'MAZAK' radiator grille - meant that new vehicles had to be supplied with dummy chicken-wire mesh grilles, on the basis that dealers would retro-fit the intended grille when production had resumed. But even these issues did not damp the demand and general fervour for the new car.
Retrospectively it is clear what a successful and pivotal model the XJ proved to be, as a means of securing Jaguar's future: No.19 being an important part of that history.
