Merlin-Royce
It was pure co-incidence that, having a book on aero-engined cars in the publishing pipeline, I was able to close the year by experiencing such a hybrid — the most powerful and intriguing motor car I have ever been out in. I refer to the Merlin-powered Rolls-Royce Phantom II built as a fun-car and to prove the versatility of the Merlin aero-engine, by the Jameson brothers, whose father designed and constructed many engines of his own. One recalls his Jameson Special racing cars, with which MOTOR SPORT has dealt recently, a 500cc racing Jameson, a supercharged sleeve-valve power-unit and a flat-four aero-engine. . .
In the Ford Sierra 4×4 workhorse I went to see this Merlin-Royce his sons Robert and Paul started making back in 1976. What a truly impressive piece of work it is! It started out as a normal 1933 12ft 6in wheelbase Pll saloon, which now has a wood-planked two-seater body and in which a Rolls-Royce Merlin engine fits snugly beneath the bonnet — extended to some 5ft 6in to conceal it. I have seen some bonnetfuls of machinery in my time, but this beats them all! The engine is, in fact, a 1945 Merlin series 114, as flown in DH Mosquitos, with the supercharger removed and what was the propeller-end driving the car’s transmission. In lieu of the supercharger, an inlet manifold was made up and a Holley carburetter installed. The drive goes via a Jameson transfer-box which steps up crankshaft speed 2 1/2 times and through a racing Jaguar clutch to the Jaguar gearbox. The back axle is standard and the gearing is now such that 1000rpm in top gear is equivalent to 80mph. Outwardly the car looks like a normal vintage-period Rolls-Royce, until, on closer inspection, it is seen that the radiator has a one inch deeper core, with smaller tubes forming the honeycomb, which increase the cooling area by 60%. There are 1500 of these tiny tubes; this special core was made by a Warwickshire craftsman, by immersing the entire structure in a bath of flux. A cooling fan is belt-driven from the front of the off-side camshaft, and the alternator from the step-up gearbox. To tame this powerful 27-litre Royce, 16in disc brakes have been adapted to the front and back axles, using Aston Martin calipers at the front, Jaguar calipers at the back. You need to see them to appreciate the work involved. The engine, which must develop some 800-1000bhp, is served by two leather-clad tanks behind the seats, each with a quick-action filler cap, the near-side one holding 25 gallons of oil, the off-side one 50 gallons of petrol, a space between them ensuring that heat from the lubricant is not transferred to the fuel. In practice the oil runs very cool and an oil-cooler once fitted between the front dumb-irons is not at present in use. Leaded four-star petrol is the Merlin’s normal diet. The usual 7.00 x 21in tyres on centre-lock wire wheels are retained, and the registration number is AXU 700. The Marchal headlamps could be changed for the correct Lucas P100s if anyone should respond.
The starting-up procedure is as impressive as the car itself. A large foam fire-extinguisher such as is to be found at most aerodromes is placed at the ready. There intrudes a piercing shriek from the boot-mounted pump that primes the dry-sump Merlin before it is started. The starter is then pressed and from the six-branch external exhaust pipes on each side of the long bonnet, which feed into big cylindrical silencers with the most wicked of short upturned trumpet-like bell-mouths, the most immense crackle bursts out. With a modicum of warming-up, the Merlin-Royce is ready for the road. In action the noise is far from excessive, apart from a howl from the transfer-box, but the performance. . ! Oh that we could have some figures; although standing-start acceleration might probably punish the back-axle unduly. Let me just say that the car accelerated like the wind, in great bursts of power, along the flooded Sussex lanes on that long-to-be-remembered, wet, December afternoon. On the wet roads it was perfectly easy to promote wheelspin as a demonstration of the latent power. Yet it seemed a perfectly practical proposition, the disc brakes bringing it quickly to heel, the bucket seats as comfortable as those of any touring Rolls-Royce, the springs smoothing out the road, with some flexing of the long chassis frame. The view down the great expanse of bonnet, from a stance some ten feet from the radiator, and the breath-taking acceleration, were a satisfying reminder of the enormous power of this unique car. It is not everyday that one takes a trip behind 27 litres of aero-engine urge.
You ask silly questions, like “What’s the mpg?”. Perhaps three-to-a-gallon, when heavy-footed. “Maximum revs?” 3000, but 3600 was permissable for five minutes in combat, before disaster might set in, and in the car that would represent over 280mph! “Have you any plans for another?” Well, yes, maybe — with 37 litres of R-R Kestrel power.
Back to the present Merlin Royce; the dashboard instruments seem normal, until you again take a closer look. Then, from this impressive fascia, you note the Ki-gas petrol-primer, with a starting magneto below it, which has to be wound furiously for starting-up, a 240kph speedometer calibrated to read in mph, neat small dials for fuel-pressure (electric feed), water-temperature, and two more for oil pressure for the Merlin’s main-bearings, and the camshafts and auxiliaries, a clock, the ammeter, and a typical aircraft tachometer calibrated 10,20,30,40 for rpm per hundred, very easy to read. Add to this pre-start oil-primer control and the starter-button and it is an imposing arrray on a smart dashboard. The advance-and-retard lever is on the driver’s side of the body, leaving the four-spoke steering wheel uncluttered by control levers. Oh, and I almost forgot that a half-inch steel plate is normally in place beneath the floor in case the clutch explodes. . . An unusual motor car! Who said motoring has now become lustreless? To investigate it was well worth the 468-mile journey from Wales and back over mainly flooded roads. Now, back to mundane things — I must go and bale out the floor of the Ford, still awash with dirty flood water. . .
W B