We had a request from a reader a few weeks ago, Geert van Herck, who asked for an overview of engines throughout the ages.
In the Sett, we are always happy to oblige our readers, and this may well turn out to be the first in a series. But because Badgers get bored just looking at technical regulations, I’m going to focus on specific examples; engines that made a particular set of regulations great.
A bit of background
But first, some current background. Current F1 cars use 2.4 litre V8 engines, with a maximum of 18,000 rpm, and produce approximately 750-800 bhp. If you’re a kW person, you’ll know that the conversion factor is about 0.75, so around 600kW. For 2014, engines will be 1.6 litre V6 turbos, but as boost pressure pays such a great part in determining output power, it’s impossible to say exactly how many bhp will result, but current calculations are indicating that the power will remain roughly the same as it is now.
The 50s and the BRM V16
So much for the background, time to look at the first F1 engine regulations ever, 1950-1953. Essentially, the rules were based on those of the pre-war Voiturette races, run for lightweight 1500cc cars as an alternative to the full-blown Grand Prix cars where Auto Union and Mercedes completely dominated. Incidentally in those days the GP cars had a maximum weight limit (750kg) not a minimum as it is today.
For the first two years of F1, there are two contenders for the greatest engine: the Alfa Romeo 158 and the BRM V16. The former was totally dominant, and the BRM mental; so it’s the latter that holds most interest in the Badger World.
It’s worth remembering that 1500cc is not big for an engine. It’s the sort of size you get in a Ford Fiesta, and around the time that BRM were building their masterpiece, MG introduced their B series engine (1498cc, which became 1798cc in the 60s for the MGB sports car) which developed 60bhp and powered the Magnette saloon. It might have been quick at the time but I drove one recently and it reminded me just how far cars have come in the last 60 years. Anyway, 60bhp was about what you’d get from a 1500cc road car; in comparison by the end of 1951, Alfa’s 158 (1.5 litres, 8 cylinders, hence the numbering) was throwing out seven times that – 425bhp at 9,250 rpm.
That’s seriously impressive, especially when considering this in the context of the second world war, with limited resources and poor quality materials. BRM were not impressed though, and were convinced they could generate 50% more power from the same engine size. And to be fair, they did. But reliability was always an issue for their V16. Perhaps if they hadn’t been so greedy they may have had more success.
Let’s get technical
In the unlikely case that you happen to have an old 1950s Ford 4 cylinder 1500cc engine lying around in your garage, you’ll know that its piston diameter is about 3.5 inches – 80.97 mm to be precise. Pick up a piston and it feels about the right size for a piston. The BRM pistons were tiny. BRM were using four pistons to every one that Ford used, with the result that the pistons had to be small: 49.5 mm in diameter – about the same size as the old Honda 90 motorcyle that sold millions throughout the world. And of course, there were 16 of these things, all attached to a single crankshaft, spinning at 11000 rpm. A recipe for disaster.
That was bad enough, but the BRM engineers were keen to generate as much power as possible and so they went to Rolls Royce and asked them to build a smaller version of the supercharger used on the Merlin V12 – the engine used in the wonderful Spitfire fighter plane.
Why smaller? Well, the Merlin was a 27 litre engine for a start, although it “only” produced around 1500 bhp in its Spitfire version. Maybe weight was an issue too. But it was damn good supercharger.
Turbochargers and Superchargers
Perhaps it’s worth reminding ourselves of the concepts of forced induction here. Both superchargers and turbochargers (aka turbos) work by forcing fuel/air mixture into the cylinder, with the resultant explosion being larger and thus generating more power than if the engine only sucks the mixture in during the first phase of the four-stroke cycle (as most road cars and current F1 engines do). The key difference is that a supercharger is driven by the crankshaft, whereas a turbo is spun by exhaust gases coming out of the engine. Both have benefits: the turbo uses “free” or “wasted” energy and so is very efficient, but has a “lag” because there is little exhaust gas being produced when there is no throttle applied, whereas a supercharger is always “on” but it constantly saps power that could otherwise be used to drive the wheels.
A typical modern road turbo, like a Porsche, will have a boost of about 1.5 atmospheres. BRM were aiming for a boost factor of six times atmospheric pressure. That’s like turning a 1.5 litre engine into a 9 litre power unit. And as a result there were problems. Cylinders cracked, and con-rods buckled. 1950s electrics couldn’t cope with igniting the fuel (which was presumably of variable quality). In short it was impossible to maintain. And sometimes impossible to start.
BRM failed to get the car running in time for the first race of the World Championship in 1950. But it did manage a few demonstration laps, at which point the spectators, including Britains’s current Queen, were treated to perhaps the most amazing F1 engine noise ever. You can try it here (in car noise starts around 3minutes in):
Returning to Silverstone later in the year (there were non-championship races in the old days, but more of that another day) the car was unable to practice but was allowed to start at the back of the grid. Except it didn’t manage to start, crippled with a drivetrain problem. Disappointed spectators threw coins at the car, still sitting on the grid. Investors pulled out from the venture.
That wasn’t the end though
But BRM didn’t give up and a month later the car became a winner in the hands of Reg Parnell, albeit in a minor sprint at Goodwood. In all over 30 victories were notched up; Fangio drove one to victory at Albi in France in 1953 but none were in championship events. Reliability had come too late, after the decision had been taken to run the 1952 and 1953 championships to F2 regulations.
It’s not inconcievable that the BRM design from 1949 could be used in an F1 car for 2014. It’s about the right size after all. It would surely be possible to produce it now and generate comparable power to modern units. But unfortunately, the regulations do not permit that – and even if they did it would be inefficient in comparison. To reduce cost and ensure a similar level of performance, the number of cylinders, the bore and stroke, and various other parameters have been fixed for the future generation F1 engine. But in 1950, BRM proved that a 1.5 litre engine can make one of the most exciting, and physically painful, sounds known to man. I’m looking forward to hearing the new generation in action.
Hopefully you’ve learned something new in this article – are you excited by the new engine regulations? Let us know in the comments…
