Pulp Friction: BMW Enthusiast Recreates The Iconic M10 Engine Out Of Cardboard

Story by Marc W. Zak
Photography by Daniel Baxter

What’s A BMW M10?

A little background for those that think BMW built an M car out of a 10-series. In a nice bit of confusing nomenclature, BMWs fastest cars are usually those with an “M” preceding the rest of the model designation, while the engines in their more let’s say pedestrian models begin with an “M” too. That’s why the E46 M3 can have an S54 inline-six, while the 325i will have an M52 straight-six. The earliest M cars like the M1, M635csi, M535i, and the European-spec M5s had motors codenamed with “M” prefixes, but they soon bore “S” designations instead, to separate them from the more common mills.

So the M10. The inline-four Hemi with a single overhead cam from Bavaria. The M10 was the bread-and-butter power unit of BMW from the early ‘60s until it was phased out in the late ‘80s. It was first released with the new class sedans, and over its nearly 30-year lifespan it has seen all sorts of modifications and updates that saw it going from 1499cc to 1990cc in road cars, and when BMW needed something to compete with in the insanely powerful era of turbocharged Formula 1, they turned to the trusty M10 base they’d built their M12 Formula 2 engines on. The F1 variant, the M12/13, would continue to develop into the middle of the ‘80s to the point where it could supposedly produce 1,400hp.

In the 1983 Formula 1 season, Nelson Piquet and his BMW-powered Brabham BT52 won the championship, and one could go out to a local BMW dealership and find a variant of the M10 under the hood of the lowliest road cars. The M10 engine family took on many forms and codenames over its career—about 3.5 million were produced—but I’m guessing not many are made out of cardboard.

A Different Angle

Before I ever knew why BMW called their cars Ultimate Driving Machines or understood the importance of power-to-weight ratios, I was first exposed to the muscle and iron coming from Detroit; more displacement was the means to more power, and subsequently, to having fun in cars. In 1980 as a kid watching my older brother drive and work on his 1968 Dodge Charger R/T, it appeared nothing could top this formula.

In that time of my life, the visceral emotions created by 440 cubic inches and the smells of gas, rubber, and oil were the very definition of automobiling. To go fast you had to have a V8—period! Growing up under this pretense led to many 5^th grade arguments with a friend whose father was a proponent of European cars with smaller-displacement engines. The likes of TVR, Saab, BMW, and Triumph in my mind were no better than VW Beetles when compared to the behemoth that was MOPAR. 

It was not until said arguments got noticed by said friend’s dad that things would start to change. He set out to prove to me that you don’t need a massive motor to make a car worth wanting. The stage was set, and still in disbelief that a four-banger could run hard, I agreed to go along as a passenger on a “test” drive of sorts. A 1973 tii was my friend’s dad’s car of choice.

My mind was changed, but I still harbored a love for the cars that got me started so during that summer with nothing to do and still unable to drive a car of my own yet, I wanted to get my hands on anything with a motor in the time being. The build idea came to me while staring at a carton of eggs. To me the 12-pack lid looked a lot like a valve cover on a V8, so I started to collect items to aid in my first attempted scale model engine build. It would not come to fruition. It got as far as the block and heads in the odd shape of a cardboard box with seafoam green Styrofoam valve covers.

Fast forward 36 years. I found myself yet again staring at materials thinking I could use this stuff to build an engine model. Reminiscing about that fateful day riding in the tii as a youth, I wanted to pay homage to the very motor which changed everything for me.

How To Build It

For me it was simple. First I collected all the needed materials like flat stock and rolled cardboard tubes. Next came the idea of using gaskets from a real engine as a datum when making the individual parts. To me it seemed straightforward enough; I had over 20 years working on the real thing as a BMW hobbyist, so making an M10 out of cardboard with a little less functionality than the real thing shouldn’t be insurmountable. In addition, as an industrial designer I know how to work materials and I already possessed handcrafting skills learned in my years of model making. The dice were cast. 

The first step in actually building my version of the M10 began with a head gasket. It provided the foundation on which I built from. Using tubes as bores, the rest followed in what can be considered simple fabrication methods. Layout, measure, cut, and adhere the part to the whole. As the block took form, my path toward completion grew clearer, and the progress was more organic than you might think, and reflected a lot of principles used in the construction of the actual motors. The gaskets were the key piece to get right on the base on mine, as they provided a dimensional reference which dictated the scale and placement for much of the individual parts built and added later. That was the plan: build each part of the motor and assemble like the real thing. 

This endeavor has been a lifelong passion which most likely took root before real automobiles entered my life, as I hand built 1:24^th scale model kits for years prior to receiving my license. Hearkening back to those days of analog model building makes me appreciate an artistic view of technology. Today with digital design and 3D printing taking over what used to be done by hand, we lose a little of the tangible sentiments and subtle artistic expression achieved through sculpting one’s vision in a more direct way. Like Michelangelo’s “David,” when asked how he did it, his reply was “Every block of stone has a statue inside it and it is the task of the sculptor to discover it.” Mine just happened to start with a carton of eggs.