To understate it, Bristols have always been a bit, shall we say, odd. From the BMW-stolenderived inline six to the eccentric styling of their roadgoing contraptions, they’ve always marched to a different drummer. Their appeal lies not in their classical beauty nor in their raw performance, for the simple reason that most Bristols lack either. Where Bristol rightly deserves credit, however, is at the forefront of post-war British innovation. Where their domestic counterparts contented themselves with frumpy traditionalism, Bristol beat alloy into lurid shapes and chased land speed records. One of their finest, and in that great Bristol tradition, most polarizing creations was the 450 Sports Prototype racer, LeMans competitor, recordbreaker, and torch-bearer for windtunnel development.

The 450’s roots lie in an ill-fated attempt to resurrect the hallowed ERA racing brand with a Formula 2 car in the early 1950s. Cursed with an unreliable motor and the failing health of their leader, neo-ERA divested themselves of the project. Bristol was the beneficiary, and the basic geometry of the open-wheeled ERA became the basis of a Bristol factory sports racer program.

Perhaps another company would have just clothed the oval-section tube chassis in enclosed bodywork and called it a day, and headed off to the pub to dissipate leftover energy on downing pints. Some components carried over with relatively little change. The ERA’s deDion rear and double-wishbone front suspensions were retained, but the chassis was converted to round tubes. Nestled up front was the familiar Bristol six, in 1971cc form, making a healthy 155 HP. With those conventional bones in place, Bristol invested some serious engineering into the sports racer, dubbed the 450. A rear-mounted transaxle helped with weight distribution. Inboard brakes reduced unsprung mass.

And at a time when knock-off spoked wheels were de rigueur, Bristol developed a highly advanced wheel arrangement, with a large central “spider” of cast spokes and five lugs, to which the actual wheel was merely the rim and tire. In some ways this prefaced the multi-piece racing wheel of much later. The hub was incredibly large to allow changement of the driveshafts without removing the wheel or the inboard brakes. And most importantly, the company developed a five-barreled pneumatic lug wrench, which removed all of the lugs quickly and at once. It then retained them within the wrench for quick and precise reattachment. This was light-years ahead of anyone else’s thinking at the time, where lead hammers and single-nut-knockoffs ruled the roost.

The most apparent innovation was in the sophisticated, streamlined bodywork fitted to the 450. Bristol was of course mainly an airplane manufacturer, and thus the 450 engineering team had access to the aeronautical wind tunnel. That being said, the initial iteration of the vehicle was awkward at best, with protruding headlights and a shovel-like snout. The rather bizarre enclosed cockpit swept back into a narrow, trailing fastback shape. This initial version ran in anger at the 1953 LeMans race, but both entrants bowed out with trouble early on. After this experience, the Bristol design team wisely decided to do something about the homely and bulbous front end, and smoothed things out by fairing in the driving lamps, with the central pair residing deep within the hood and peering out through a large glassed in section. While it looked odd, it was better and more aerodynamic than the previous iteration. In this second variation, it set several endurance and speed records.
The following year, running minor modifications to the engine, the 450 managed a 1st in class and a 7th overall finish at LeMans, an impressive showing for a repurposed Formula 2 car, although the 450 was really the only competitive can in the 2-liter class that year. The big changes came for 1955, when the 450 got a top-ectomy.

The probably apocryphal story is that drivers were sick of the fogging plauging the dreary 1954 season, but it’s more likely that the extra weight of the top didn’t justify the reduction in drag. Whatever the reason, the Bristol sports racer got a much spiffier-looking roadster body, and let us be honest for a moment and say it had a passing resemblance to the contemporary Jaguar LeMans entries. Imitation = flattery, I suppose. Unfortunately, despite promising top speeds in tests, the entire 1955 season was overshadowed by the horrific disaster at LeMans that year, and no one much cared how the contestants fared in a race that most feel should have been discontinued immediately after the accident. With the end of the season, three of the four 450s were scrapped and one, comprised of the best bits of the other 450s, was retained by Tony Crook, the enigmatic chairman of Bristol and a former racer himself. It survives to this day wearing the open bodywork.
Sources: BOC.net, wikipedia ,