BMW E9 Coupe Was Cut Up To Hide A 394-HP M5 V8

Frankenstein builds don’t have to be pretty, but this BMW E39 M5-based E9 defies the usual convention by looking like it came straight from the factory.

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MKO CS M5 based on BMW E9
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One of the Prettiest BMWs Ever Made

BMW has a lot to put in its greatest-hits catalog, but one could say that the E9 coupes from the ’60s to the mid-’70s are among the best-looking cars Munich has ever produced. Initially styled by Giovanni Michelotti and further refined by Wilhelm Hofmeister, its distinct profile defined an era at BMW and would set the template for its eventual successor, the 6 Series.

It didn’t matter if it was the road car or the race car, the E9 looked great wherever it went. The car had style and substance in spades, and it had a successful racing career to back up its credentials. Without the E9, BMW M might be a different company, or probably wouldn’t exist at all.

With such a classic and iconic shape, the thought of cutting one up is pretty horrifying. But if it’s done right, it can transform it into an elegant hot rod.

1971 BMW 3.0 CS (E9)

BMW

Meet the MKO CS M5

MKO GmbH and Co. is a workshop and car dealer based in Germany that specializes in V8s. As the E9 was never available with eight cylinders, the shop decided to throw one in under the hood of the classic car. However, it wasn’t going to be a simple swap, as it would require two E9 coupes and an E39 M5 to get it done.

The result was the MKO CS M5, completed over a decade ago. It has since appeared in several publications before being sold into private hands. Now, it’s up for sale on Bring a Trailer with a current bid of €42,225 at the time of writing. That’s about $49,000 at current exchange rates.

MKO CS M5 based on BMW E9

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The Build

As mentioned, it took three cars to complete this one special vehicle. Fabricated in Romania. The entire lower half of the car is pure E39 M5 under the skin, while the top half is all E9. The floorpan was then shortened to stay true to the classic coupe’s proportions, and considerable work went into turning it into a two-door.

The car gets the E39’s modern suspension arrangement, and at the heart of it all is the 4.9-liter V8 straight from the M division. It’s unknown whether the engine received any upgrades, but with its lighter body, the 394-hp mill should make light work of going fast. As it’s mechanically an E39 M5, it comes with a six-speed manual and a limited-slip differential. It also has KW adjustable coilovers to keep things nice and planted.

MKO CS M5 based on BMW E9

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Frankenstein Done Right

From the outside, it looks like a 3.0 CSL, and the only giveaway is the quad exhausts at the back. It previously rode on Style 65 wheels straight from an M5, but it’s now on 19-inch Alpina wheels. On the inside, however, the dash is straight from the ’90s 5 Series, along with other mod-cons.

Of course, the purists won’t like what’s been done to it, but we can take a moment to appreciate the effort that went into this car. The final result could’ve easily been butchered, but it’s well-resolved and executed. We’re also pretty sure that completing it cost a lot more than the current bid.

MKO CS M5 based on BMW E9

Bring a Trailer

About the author

Anton Andres

News Editor

Anton Andres is a news editor at Autoblog and a motoring journalist with more than a decade of experience in the Philippines. He was features editor for Top Gear Philippines from 2022 to 2025 and features and road test editor for Autoindustriya.com.