The Rover BRM Le Mans racer has been restored to running condition so it is possible (in the same way as it is possible that you might find yourself with the world's biggest gold mine in your back yard or that you might accidentally discover cold fusion) that you may find yourself in need of driving instructions for it.

Wonder no more, because I'm going to tell you how.

First though, some tech talk. Gas turbines, like four stroke piston engines, operate on a suck-squeeze-bang-blow process. Unlike a piston engine these four stages happen simultaneously in different parts of the engine. The compressor blades at the front look after the sucking and squeezing, the banging happens in the combustion chambers and then the blowing happens out the back. On its way out the exhaust gas passes through the turbine which powers the compressor blades up front. Rover had the idea, followed also by other automotive gas turbines, of fitting two sets of turbine blades. The first of these drove the compressor as above, the second or power turbine was on a separate shaft and therefore not connected directly to the rest of the engine. It follows then that we've got the makings of a fluid coupling here, with the fluid in this case being exhaust gas rather than hydraulic fluid. The engine can therefore run while the wheels, which are directly driven by the power turbine, remain stationary. No clutch then and we can do without variable gears as well if we have to. Rover did. They fitted a reverse gear to comply with legal and race requirements but drivers were warned never to use it as pausing or sticking in neutral would result in the now unhindered power turbine over speeding. We therefore just have pedals for stop and go to worry about.

Now, to start. This is surprisingly simple, you just turn on the ignition and the starter. This runs the engine up to 20,000 rpm at which point it will begin to sustain itself. The starter stays online until 30,000 rpm at which point it automatically cuts off and the engine then builds up to its idle speed of 35,000 rpm. At this stage it'll begin to creep (remember, the engine acts as if it has a fluid coupling) so you'll need to plant your foot on the brake until you want to proceed. Take your foot off and the car will creep all the way to about 40 mph. Apply full throttle and it'll move away in a fairly gentle way until the engine approaches its maximum of 65,000 rpm and acceleration becomes brisker. Just as an indication of how slowly it builds up power, 30 mph comes up in about 5 sec and 60 in about 11. For a racing start, you have to stand on the brake and then the accelerator, wait for a good head of steam to build up and then release the brake. When racing you have to use both pedals simultaneously in order to avoid losing revs.

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So there you have it. How to drive one particular type of turbine car. For another type, head off to Jay Leno's Garage on You Tube where he'll tell you about his Chrysler.