The comedian car guy shows off his own restored sports car powered by a chain-drive transmission
When we think vintage of British sports car with inline-6 power, we typically conjure up images of classic Jaguars and Aston Martins. But this week on Jay Leno’s Garage, the comedian features a much lesser known sports car that fits that description.
That car is a 1934 Frazer Nash TT Replica from Jay’s personal collection. Like other British sports cars from that era, the Frazer Nash has a straight-6, but the rest of its drivetrain is rather unique. The unique part is its use of a chain drive, like you’d find on a bike, rather than a conventional automotive gearbox.
A series of four sequential chains (one for each of the four forward gears) transmit engine power to the rear wheels, and there is no clutch, allowing for rapid gear changes via an external shift lever. According to Jay, the Frazer Nash’s clutch-less gear changes made it the fastest non-supercharged vehicle of the era.
The Frazer Nash also has a few other unique mechanical items. Since its rear wheels are driven by a set of chains along a single axle, there is no differential, meaning the rear wheels are locked (normal cars use a differential to allow the outside wheel to spin faster than the inside wheel). Because of that unique feature, Jay says the Frazer Nash is easy to slide around corners and was a favorite among hillclimb racers in its day for that very reason.
Steering is also extremely quick in the Frazer Nash, which was likely another reason for its popularity among the racing set. In about three-quarters of a turn of the steering wheel, the car’s front wheels go from lock to lock. The cars we drive day to day usually take three or four turns. You can see how quick the steering it and the adjustments Jay has to make because if it when he takes the car for a driver later in the video.
Powering the chain-driven Frazer Nash is a 1.7-liter “Blackburn” straight-6, which was a rare upgrade over the car’s standard 4-cylinder. In fact, Jay says the company built only 26 Blackburns. Jay doesn’t reveal the engine’s output, but it’s likely impressive for the year. The straight-6 features three carburetors, dual-overhead cams, and a hemispherical head. It also sounds wonderful at open throttle thanks to a Brooklands-style muffler. The only modifications to the vehicle are a small tool storage area in the back and an electric fan to keep the engine cool in the California heat.
Although in perfect working order now, the car was a basket case when Jay found it in a collection in Washington state a few years back. The car needed basically everything, but the cracked crankcase and worn out chain drive were the toughest tasks for Jay’s team of mechanics. The crew ended up 3-D printing a new crankcase and modifying modern motorcycle chains to work with the car’s drivetrain.
Don’t go thinking this car is a fake because if its name. Frazer Nash called this particular model Replica because it was a replica of the company’s racing car at the time.
This article was originally published by Motor Authority, an editorial partner of ClassicCars.com.