1977: Transmission change
January
During the early months of 1977, a significant mechanical change was made when the original Borg Warner automatic transmission unit was replaced by the General Motors GM400 three-speed unit. Manual transmission was still available for customers who preferred this.
June
In the USA, British Leyland Motors Inc. (which afterwards became Jaguar Cars Inc.) took the decision to celebrate the Queen’s Silver Jubilee in 1977 with the introduction of a special XJ-S. There were no mechanical modifications to this model but special features included 14 coats of hand rubbed silver and gold paint, Royal purple stripes, Official Silver Jubilee badges and a silver leaping Jaguar was mounted on the roof just behind the windscreen, and around the Jaguar’s neck was a collar studded with 3 amethysts.
July
For the 1977 season, the SCCA permitted category 1 racing manufacturers/owners to modify their cars to a greater extent. The rules were similar to those of the production series races with the added ability to reduce the body weight considerably and make dramatic modifications to the body styling. The implications of which were to improve the aerodynamics and accommodate wider rimmed wheels. During the winter months, Brian Fuerstenau carried out an engine development programme where the result was a power output exceeding 500bhp and Lawton Foushee engineered a styling programme that meant a complete rebuild of the car.
Various studies of specifications were done, and the power-to-weight ratio of competitive race cars was analysed. This led Jaguar to speculate that a Group 5 XJ-S should not weigh more than 2541 lb (1155kg). However, the Group 5 XJ-S racing project was terminated after numerous hours were spent, including drawing office time, component drawing and fabrication. The termination of the project coincided with the cancellation of BL’s Broadspeed racing programme and Bob Knight’s promotion to Managing Director of Jaguar Cars. Bob Knight remained with Jaguar for two years following his appointment, and retired as John Egan became Chairman. All racing activities and studies ceased at this point, the company had to look at its survival as a maker of road cars and could not spend funds on projects which did not guarantee a return that would secure the livelihoods of the workers, shareholders and ultimately supporting the customers.
Throughout 1977, Jaguar investigated a number of aerodynamic issues concerning the XJ-S. They found that the main problem was excessive front end lift, which they tried to reduce without success. Another problem was the fluid operating temperatures, which had been one of the issues Broadspeed identified on the XJ12C. Abbey Panels became involved with major modifications to the body structure which included a complete rebuild of one of the cars on 20 July 1977 with specific instructions from Malcolm Oliver:
“For the purposes of this assessment, it has been assumed that the vehicle will be built to as competitive a standard as possible without the use of ‘exotic’ materials”.
The XJ-S advertising campaign in America at the time was titled “Thundering Elegance” and it depicted two XJ-S cars, one was the Trans-Am XJ-S that was being raced by Bob Tullius’ Group 44 and the other was a standard XJ-S. The 1977 Trans-Am racing season started for Group 44 chassis 2W 51120 saw five victories in ten races, Bob Tullius won the Trans-Am category 1 championship but had insufficient points to clinch the manufacturer’s title for Jaguar.
September
Production changes to the 1978 model year included the matt black boot lid panel replaced by a body coloured panel and a new quartz time clock was introduced.
November
Michael Edwardes was appointed Chairman of British Leyland in 1977 and began to turn BL around, encouraging individual marques to assume their separate identities once again.






