X-Ray spec: BRM V16
British racing’s great hope in the early 1950s was a BRM with a V16 engine, but its vicious power delivery rendered it hopeless. By Keith Howard
Hangovers from the VJ day celebrations were still a recent memory when, in November 1945, Rolls-Royce generated its first internal report into how its two-stage supercharger know-how — which had made the Merlin and then the Griffon the most powerful aircraft piston engines of WWII — could be adapted to the rather different needs of motorsport. It was the first technical step in a racing project whose aims were as much political and economic as sporting.
BRM’s grand prix challenger, supported by some of the top companies in the British engineering industry, wasn’t contrived just to erase Germany’s pre-war hegemony or subdue the rebirth of the Italian scuderie. In a world where political and economic power had shifted decisively towards the USA and Russia, the BRM V16, as we now know it, was intended to remind everyone that Great Britain Ltd still packed a punch.
When the great hope proved to have a glass jaw, the recriminations began: the car was overly complex and expensive, even though it consumed a fraction of the fortune Germany had spent supporting Mercedes and Auto Union in the 1930s. Worst of all, it was fundamentally wrong-headed. By being, in effect, a reiteration of the ERA E-type in its chassis and suspension, it squandered opportunities that smaller, cash-strapped outfits like HWM would soon exploit. And its centrifugal blower guaranteed an all-or-nothing power delivery that made it unfriendly to drive.
It wasn’t only armchair critics who said as much. Stirling Moss tested the car at Monza in 1951 and afterwards sent Raymond Mays a long list of its faults. In The Design and Behaviour of The Racing Car, co-written with Laurence Pomeroy in 1963, he remembered it as “unstable on the straight” and “impossible to drift in corners” because of the engine’s sudden power delivery. It was “a terrible, not to say terrifying, piece of machinery”.
Yet in his autobiography It Was Fun, the late Tony Rudd — who was seconded to BRM from Rolls-Royce in 1951 to keep an eye on developments there, and never returned — staunchly defended at least one of the car’s most maligned features: that two-stage centrifugal blower. As he recounts, it was chosen for sound engineering reasons, being smaller, more efficient at high boost pressures and more reliable than the Roots or vane alternatives. And, as reported at length in an Institution of Mechanical Engineers paper published in 1964/5, R-R was not unaware of the power delivery issue and went to considerable lengths to design around it.
The reconciliation of these polarised views lies, perhaps, in the timescale it took to iron out the car’s problems. When Moss drove it at Monza he was appalled to find it still unraceworthy after two years of development. Eventually the V16 engine did deliver prodigious power (an estimated 625hp at an incredible 85psi boost pressure) and was made acceptably reliable. Likewise, the worst of the handling shortcomings were at least ameliorated. Had the car delivered something like its final performance in 1951/2, as it should, then it might have written itself a different epitaph. Its potential is confirmed by Rick Hall of restorers Hall & Hall, who talks about it overleaf. Nobody knows the V16 better than H&H, who have rebuilt four of them — two Mk 1 s and two Mk2s — and are manufacturing three new V16 engines.
In its way, though, BRM’s great folly did prove to be an important catalyst. Tony Vandervell resigned from the BRM Trust in disgust in 1951 and determined to mount his own grand prix challenge, involving a certain Colin Chapman along the way. When Vanwall clinched the constructors’ title in 1958, it signalled the beginning of Britain’s dominance of F1. And that — as BRM’s visionaries had hoped all those years before — persuaded the world there were some things GB Ltd could still do supremely well.
Reputation isn’t everything
Rick Hall has driven the V16 extensively, particularly the Mk2 which differs from the pictured Mkl in having a shorter wheelbase, rack and pinion steering gear and a solid de Dion axle. Although he recognises the car’s faults, he believes history has been unkind to it. “Yes, all the parts are overengineered and it would appear they had plenty of time and plenty of money when they made it. There are a lot of things you wouldn’t do that way now, a lot that could be simplified. But they were trying to build a piece of engineering with which to take on the world. In a way it’s daunting to drive because of its reputation. I remember Patrick Lindsay being wary initially but he was seriously quick in it. Once you get to know the car and what you can and can’t get away with, it’s a fabulous machine.”
“We limit ourselves to round about 10,000rpm [the engine was designed to run to 12,000rpm] and use only about 28-30psi boost pressure, but we’ve seen well over 400hp on the test bed. Mechanically, the engine is basically sound and we’ve probably done between 6000 and 7000 miles in Tom Wheatcroft’s Mk2 without a problem, just lapping the valves in a few times.”
Although the basic suspension design — trailing arms at the front and a de Dion axle at the rear — were carried over from the pre-war E-type ERA, designer Peter Berthon ditched the torsion springs and lever arms for an inboard Lockheed strut that combined damper and air spring in one unit. When these were raced they suffered friction problems but at today’s gentler pace they work okay. “I guess when they used them for grands prix they got hot. For the amount we use them, they’re fine, especially when you think there is no actual spring and of the amount of work they are doing. The inner workings are like an Armstrong [monotube] shock absorber. One half is filled with liquid silicone and the other with pressurised air. We find 300psi works well, with a little less on the front. But it’s a bit exciting if you forget to release the pressure when you’re working on them. The check strap is a steel rope: otherwise there’s nothing to stop it pulling apart on wheel droop.”
Initially the V16 was sparked as illustrated here using four coils and four distributors, driven from the camshafts. Today the cars are fitted with the later magneto system. “The biggest problem we have with the engine is with the ignition,” says Hall. “I don’t know why but the Lucas magnetos are a source of problems once you get heat into them. We have had them rebuilt by everybody, but it makes no difference. What happens is that as you get heat soak, you lose revs — every lap there seems to be about 500rpm less available. When I saw Tony Rudd some years ago and he asked how the V16s were going I told him about the problem and, without having to think about it, he said ‘Bloody magnetos!’, so it’s an old problem. If I could put something modern inside those, I think the cars would run a lot better for a lot longer.”
One of Moss’s criticisms of the V16 concerned its cockpit layout, which prevented him using his favoured straight-arm driving position. “It’s a very big car but there’s not a lot of room in the cockpit. Reg Parnell’s knees must have been around his elbows.” Driver comfort was made even worse by the car initially having its twin exhaust systems housed within the bodywork as illustrated. At the British GP in 1951, Reg and Peter Walker both needed medical attention after the race because their feet had been blistered by the heat. “They soon brought the exhausts outside to cure that, but even so it still gets quite hot in the cockpit. When the engine is on the test bed, the short exhaust stubs glow red hot, and sometimes more than that. It must have been like being in an oven with the pipes running inside the bodywork.”
On its first public outing at the 1950 International Trophy race at Silverstone, the V16 suffered its most ignominious mechanical failure when a driveshaft broke at the start. The lesson was not unheeded. don’t know what the first driveshafts were like — I haven’t seen the one that broke — but BRM certainly made sure that this would never happen again. The driveshafts are heat-treated, balanced and polished maraging steel forgings and beautifully made — a work of art, as BRM driveshafts always were after that, right up until the finish. The driveshafts cost a fortune to make but very rarely gave any more trouble. I remember in the early 1970s other teams wanting to buy them because they had driveshaft problems with the Cosworth, but BRM would never sell.”
‘We run the V16 on an 80:10:10 mix of methanol, fourstar and acetone these days, this being a blend that one of the major oil companies recommended to us. We’ve tried all sorts and that’s the mix it seems happiest on. I don’t really know the fuel consumption, but I suppose we get about two or three miles to the gallon. We put 25 gallons in it at the Goodwood Festival of Speed, just to warm it up and go up the hill a few times, and we ran out, so it’s amazing what it gets through.”
“None of the Mk I shave the original three-shoe drum brakes fitted now. In fact, I’ve never seen any of those. They all have the six-pot Mk2 discs instead. The pads are round and bonded directly to the caliper piston. They’re fantastic brakes when you get them right, they really are — extremely effective with very light pedal pressures.” The only brake problem is pad knock-off, caused by hub flexure— a problem that was solved in the Mk2 by the fitment of non-return valves. ‘That’s the biggest problem we’ve had with the Mk1, because those valves aren’t fitted. It can be quite scary the first time it happens, but ifs something you learn to live with it. You just brake a bit earlier and give the pedal a couple of initial jabs.”