Most of us collect cars, almost no one collects engines. A shame really. But then again, who has that kind of garage space right?
The engine is the heart of any car and like the heart, we would rather it stay in the engine bay unless it has 12 cylinders and red crackle finish on the cam covers.
While V-12 engines are undoubtedly the equivalent of the supermodel in the engine world, it’s the four-cylinder units that are the fat bottomed girls who, according to Freddie Mercury, make the rocking world go round.
So let us look at five legendary four-cylinder engines that keep us motoring along for decades.
In no particular order, the best classic four-cylinder engines of all time are the Alfa Romeo boxer, Austin A-series, Honda E-series, Subaru boxer and BMW’s M10.
Alfa Romeo boxer
The sound that this engine makes is enough to make it a legend. If you have ever been in an Alfasud at full song and not had the hairs on the back of your neck stand up at full attention, then you are dead inside.
The earlier motors with carburettors didn’t just start and idle but had a rhythm, even at idle, that gave an impression that it was a living thing and not just a collection of metal parts.
I remember just sitting and listening to the rising and falling revolutions and thinking how it was possible to make music with just four pots banging.
The boxer revved rather freely and had an exhaust note that crackled under minimal prodding and that music made gearshifting a lot of fun.
Since the engine loves to rev, most drivers just keep it on the upper reaches and enjoyed the music, so if you get yourself an Alfasud, you may find that the fifth gear is underused while second to fourth are well worn.
Sadly, the engine was not particularly powerful; the first batch of 1.2-litre motors cranked out about 75 horsepower and that number increased to 1.7-litres breathing through 16 valves that produced 135 horses and found home in the 146.
This little engine worked for the Turin carmaker for 25 years from 1971 before being replaced in 1997 by a more conventional in-line four.
While Alfa Romeo’s boxer may sound great, it was neither the best nor is it the first one to market. That honour has to go to Subaru and their persistent love affair with the flat-four.
The Subaru 1000 came with a 977cc flat four which was derived from parent conglomerate Fuji Heavy Industries’ horizontally opposed aircraft engine.
The flat four is inherently smoother than an in-line engine and the low vibration was a major consideration in aircraft design where metal fatigue is a critical issue. The low frontal profile of the engine also meant it was easier to make aircraft cut through the air smoothly.
When Subaru introduced the 1000, the car looked pretty conventional but underneath the skin was an advanced lightweight chassis and the engine is a fantastic powerplant.
Maybe it’s their zen approach to engine design and motorcycle maintenance, so Subaru stuck on with the boxer engine and evolved it into one of the finest jewels in the automotive industry, producing great music, fantastic power and awesome torque with the help of advanced turbocharging.
In the world of in-line four cylinders the Austin A-series engine deserves a mention because if you drive a British car from the 1950s till the late 1970s and the very last original Mini in 2000, chances are you have a British Motor Corporation A-series engine under the bonnet.
The engine first appeared in the Austin A30 in 803cc form and grew to it’s final size as the fabled 1,275cc that powered many hot British cars.
The reason why it lasted so long was because it was fundamentally correct from the get-go; the Harry Weslake-designed engine was a tough little cast iron unit that was tough as nails.
Weslake is legendary when it comes to cylinder head and the one he designed for the A-series gave it good breathing so it could be continuously enlarged and improved to keep up with the times.
The engine was licensed by Nissan and became the basis of many of their engine designs since.
Truth be told you can probably trace some of the engineering roots of current Nissan four-cylinder engines to that venerable A-series.
The 50-year lifespan of the engine made it one of the most common engines in the world and almost certainly the most common engine in the classic car world.
Meanwhile in the late 1960s, Honda was looking for ways to improve combustion to produce more power with less fuel.
Actually, no one knows if they were looking for more power but Honda was certainly looking for ways to clean up their engine and pass new emission rules without the need to admit failure and resort to expensive catalytic converters.
Improved combustion is the real way of achieving cleaner burn but that is a lot easier said than done in an engine that has to work at various speeds and under different loads and varying external conditions, from fuel quality to atmospheric pressure to differing ambient temperatures.
They came up with the unpronounceable but cool looking CVCC badge for their cars to tell the world that it had Compound Vortex Controlled Combustion.
Basically, the engine has a pre-chamber to help air and fuel become better friends and work harder in the combustion chamber. The technology came at just the right time, when oil prices spiked in the 1970s and made Honda a popular little fuel sipper.
The final engine on this list is BMW’s M10 series which powered everything from their Neue Klasse until the E30 3-series of the late 1980s.
That’s a run of nearly 30 years
The most impressive thing about this engine is that it forms the basis of the first M3 engine called the S14 and, more impressively, it is the very foundation of the M12/13 motorsports unit that powered even their Formula One engine.
In those heady days of unlimited engines, BMW produced M12s in qualifying trim the mid 1980s seasons that could produce over 1,000hp; some say they went as high as 1,200 hp.
I personally think that the M10 engine is the best of the best because it powered everything from the most basic four-door sedan that BMW built and the most powerful F1 car of the time.