75 YEARS OF THE XK ENGINE Every manufacturer has an engine that is a staple of the brand. For Ferrari, it’s their sonorous V12, for Honda, it’s their legendary VTEC H2OC and for Jaguar, their breathtaking, reverberating, 75-year-old XK straight six is what established them as a brand. This revolutionary engine lasted 43 years, from 1949 to 1992. In that time, it powered Jaguar’s most iconic and greatest cars, assisted them to championships in racing, and even found itself in use by the military. Such a special engine deserved quite a special birthday. That’s exactly what happened at the 26th Goodwood Revival. Why is this engine so beloved? Let's find out. THE HISTORY OF THE XK ENGINE 1948, the day of the London Motor Show, Jaguar’s first-ever concept sports car, XK120, graced the world. Powering it was a 3.4L 160 brake-horsepower XK straight six, that had begun production during the Second World War. The engine was intended to be utilised in the Mk7 saloon, but owing to the high demand, it was agreed the 120 enter production as a showcase of the engine’s capabilities. And boy was it a showcase. At 126mph, the XK120 quickly became the world’s fastest production car and earned countless victories in many sports car championships. Production increased from 200 to 12,061, and Jaguar became the highest-exporting brand in the UK. Throughout its run, the XK Straight Six went through five displacements (2.4L, 3.0L, 3.4L, 3.8L, and 4.2L), but its philosophy of putting Jaguar at the top remained consistent. Jaguar dominated LeMans in the 50s, with the C Type taking victories in 51 and 53 and the D–type dominating from 55 to 57. And who can forget Jaguar’s Magnum Opus, the E–Type, a legendary beauty that killed all its costlier rivals? Jaguar’s saloons also benefitted from the XK straight six. During the early sixties, the Mk1 and Mk2 were the kings of the Touring Car scene, the Kray Twins could outrun the police in their 420Gs, and three generations of XJ6 consistently utilized the engine from 1968 to 1987. The engine eventually found purpose in the Military Light Combat Vehicle Reconnaissance Tanks before ending in the 1992 Daimler DS420. At 43 years, the XK Straight Six officially became the second-longest-produced engine, a record that wouldn't be surpassed until 2001. THE CELEBRATIONS AT THE REVIVAL From the 6th–8th of September, Jaguar was the brand to behold at the Iconic Chichester Hillclimb. Across three days, iconic XK straight six-powered cars paraded around the race track. One of which was a 1954 D–type prototype owned by the Jaguar Daimler Heritage Trust. “Jaguar Classic,” the company’s classic continuation programme showcased a selection of cars at their stand, including a 1951 XK120, one of their continuation 1953 C–types, the 1988 Le Mans winning XJR-9 LM and a 2024 Formula E winning I–Type 6. “Jaguar Classic” also entered their first-ever race this year with a 3.8L Mk2 Saloon at the St Mary’s Trophy bow. The first on Saturday was driven by Goodwood regular Nic Minassian, and the second on Sunday by Jaguar’s TCS reserve driver Joel Erikson. Neither took the car to a top 10 space. On a brighter note, 5 out of the 16 races saw a classic Jag earn a top 5 position, two of which were actual victories. On Friday, an XK150 FHC won the FordWater Trophy and on Sunday, a Lister HWM reigned supreme in the Ford Water Freddie March Memorial Trophy. Even 75 years on, the XK straight six continues to shine. HOW THE STRAIGHT SIX IMPACTED JAGUAR? Unlike most manufacturers, Jaguar doesn’t build an engine to outperform their competitors. They build one to do so for many years to come. The XK Straight Six is clear proof of this as is their recently deceased, 30 year old V8. Currently, Jaguar are replacing their ICEs with a new range of EVs and judging by their recent 2024 Team’s Championship Victory in Formula E, the future looks bright. After all, the XK Straight Six won races before it ruled the roads. And if history is anything to go by, their electric power plants will last longer than almost all their competitors. CONCLUSION The XK Straight Six’s legacy is legendary, proof that Jaguar is an innovator of preservation. It launched Jaguar as a global brand, establishing them as game changers in the automotive sector. The slogan, “Grace, Space and Pace”, would not exist if not for this world class engine.
