Car engines are strange designs, different at least because they can be appreciated on many levels.
Firstly, there is the aesthetic; appreciating the engine visually, either in situ or out of the car and certainly in dismantled, component form. Then you can appreciate them aurally, as so much has been said and written on the sound effects produced by so many popular performance cars it would be foolish to omit this quality. And lastly, and engine can be admired for the performance that it endows the car in which it is installed in with. The on-paper specifications can be impressive, but ultimately as a design, all the dimensional representations of an engine can amount to naught if it doesn't deliver some level of exhilaration, or at the very least - some satisfaction.
So it is with that introduction that I choose to deliver one of the most pleasing engines that any common man can lay their hands on - the Alfa Romeo, horizontally opposed four cylinder. This engine was introduced in 1971 in its diminutive 1186cc form as the motive power for the then, all-new Alfasud.
The engine was as the rest of the car, a radical departure from most of what Alfa Romeo had always stood for; for starters it was a front-wheel drive car. Secondly, the engine itself had four, horizontally-opposed cylinders with overhead valve gear driven by a single overhead cam. That, for a company who's reputation hinged on their sonorous DOHC 'fours' was unusual. Stranger still, that single overhead cam was driven not by the altogether commonplace duplex chain drive, but by a pair of toothed rubber belts, and induction was courtesy not of the paired Webers that by the early seventies had become de-rigeur on Alfa Romeo engines, but by a single ventura, Dell'orto carburetor!!
The early versions delivered just 63bhp, but it is right here that you develop a fondness for this engine. Its delivery, as a free-revving, aural delight is what really satisfies. As the revs gather, the engine smoothens right up to its lofty 6750rpm red-line. Noteworthy: at the time that the Alfasud was being developed, Alfa's racing arm 'Autodelta', was winning the world sportscar championship with 12 cylinder boxer engines, and whilst it is intangible as to how much of that technology found its way into Alfa's baby, there can be no doubt that some spirit rubbed off.
The flat four grew in size, first to 1.3 litres and then on to 1.5 whilst the fuel delivery was up-specced from the original 32mm Dell'orto to a dual throat Weber, then paired Weber IDA's before the ultimate 1.7 litre versions were gifted with DOHC 4 valve heads and nearly 130bhp.
In any iteration, the engine is a delight to spin out to its rev ceiling, take in the rasping exhaust note and savouring the the power delivery through the front wheels.
Like many boxer engines, it is a visual disappointment when fitted in the car. Early versions are dominated by the large, round tin air cleaner that later became ribbed plastic on Alfasud tis. Later still, the twin carb engines were a slightly prettier sight with a carburetor and manifold sprouting out of each head, joined by a flat, oblong filter arrangement but all the castings and exhaust manifolds remained hidden, under the engine - a legacy of the boxer engine's purposeful design that bestowed it, and the cars that it was fitted in with qualities well beyond their often mundane and utilitarian day to day commutes.
Many frailties can plague these engines, but the thrill of the start up, the enjoyment of exploring its limits and the sound of its exhaust note are worth every headache.
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