Тhe boxer engine stands out in the realm of internal combustion engines for its unique design and distinctive sound. Unlike the more common inline or V-shaped engines, the boxer engine, also known as a flat-four, boasts a configuration where its pistons move horizontally in opposite directions, creating a perfectly balanced force. This configuration is renowned for its smoothness, low centre of gravity, and the unmistakable purr that has become synonymous with the Subaru brand.

It's this exceptional design that makes the flat-four engine a favourite among many automotive enthusiasts. And when it comes to celebrating the art of engineering, no one does it quite like the YouTuber JohnyQ90. In a recent video featured on the channel, we are treated to a mesmerising showcase of precision engineering – a fully functional miniature flat-four combustion engine. The level of attention to detail and craftsmanship that goes into this diminutive marvel is nothing short of astonishing. But what makes miniature engines like this one so cool, and why is this miniature flat-four particularly impressive?

The beauty of a miniature engine lies in its meticulous design and the dedication required to make it fully operational. Just like full-sized engines, these miniatures must adhere to the same engineering principles, making them a true test of an engineer's skill. They require precision machining, careful assembly, and an acute understanding of the mechanics involved, often demanding an unwavering commitment to perfection.

In the case of the miniature flat-four combustion engine featured on JohnyQ90's channel, the attention to detail is awe-inspiring. The video takes us through the step-by-step assembly process, showing how each component, no matter how small, is fitted into place. Every piston, rod, and camshaft is a work of art in its own right. 

One of the most astonishing aspects of this miniature flat-four engine is that it not only looks the part but also sounds like a small Subaru engine when it's fired up. Not everything is perfect from the first attempt but after a few small tweaks, the motor works fine. At full load – at around 10,500 rpm – the little mill produces around 120 watts of power, which is around 0.16 bhp. And hey, that’s enough to power an H7 bulb!