That's exactly what Michael Oberhauser of the German garage MKO did, joining the legendary E9 CS looks with the characterful E39 M5 powertrain to create a perfect modern day classic.
There are restomods and then there's the MKO CS M5. It wasn't just blessed with a simple engine swap or a new set of wheels; this car is so much more than that. In fact, what you see here is a regular late '90s BMW M5 E39 with an original '70s CS Coupe E9 body spread over its modern mechanics like a gorgeous topping covering a tasty doughnut. If you want to call it a restomod project, then this is the ultimate one, the furthest it can go, both in terms of quality of the work and the choice of the cars.
When the BMW 'New Six' CS was shown to the world back in 1968, the world responded in awe, struck by its pure beauty and effortless luxury. Both of these had been present previously in Munich with mixed fortunes, but the model now more widely known as the E9 coupe played a pivotal role in paving the way for the premium performance position BMW holds now. Specifically, CS gave birth to the great lineage of grand BMW coupes, with all of the models to follow bearing the Series 6 designation.
On its own, that's reason enough to put CS in your personal BMW Hall of Fame, and that's even before we get to the faultless looks of this classic two-door. After the 503, 3200 CS and 2000 CS coupes failed to win a unanimous approval of the crowd that would provide a significant sales record, the modern looking E9 series achieved an unprecedented success with the total of more than thirty thousand expensive coupes leaving the subcontractor Karmann's factory gates over the eight-year production cycle. The E9 did that with all the ingredients that had shaped the BMW greatness. Not only did it write the basics of the BMW design rulebook that is still valid today, but it also made the straight-six engine famous and proved its credibility with countless race wins in European Touring Car Championships and Deutsche Rennsport Meisterschaft (the predecessor of today's DTM).
All that happened in the times when our peers got excited by seeing Neil Armstrong landing on the moon, got stoned at the Woodstock festival and was shocked by the Beatles breakup. These were surely memorable times, but by modern standards, the cars then weren't so great or fast, in particular. Even the more powerful 3.0 variant of CS that came out in 1971 couldn't get past 200 bhp, which translated to the 0-60 time of 7.5 seconds and 140 mph top speed. Today, that CS would have been comfortably outpaced by most of the BMW lineup, including the diesel 3 Series city dweller. The "never meet your heroes" saying doesn't apply only to people, you know.
But such a special and lovable Bimmer as the E9 deserves to be still perfect and impressively fast. It needs to be. And, in fact, we're not the first to think so. That's a good thing, as all I could do to make E9s faster was to write a mournful story that won't change thing, but you can always count on some determined and knowledgeable Germans that will take the matters in their own hands. The small garage of MKO is one of those companies that make the German car scene as crazy and great as we know it. It's that kind of place that creates some silly projects with a very serious and competent attitude that somehow makes a fascinating car you won't find anywhere else. And companies such as this one exist into Germany thanks to the petrolheads like Michael Oberhauser, the chief and founder of MKO. In 2007, he decided to sell his prosperous engineering company to fulfill his livelong passion. Four years later, he had a shiny new showroom and a big garage with a MAHA dyno and a few cars to fill it. Michael has a weak spot for V8 engines, both those that he imports to Germany in many old and new American cars, and these few that he puts under the hoods of inconspicuous classic BMWs. The first job of the company named after the initials of Michael and his understanding wife Katherine was a charming classic '75 BMW 1502 with a naturally aspirated M60 V8 engine that used to power 5, 7, and 8 series in the mid-nineties. Good for 286 hp, it made this small vintage coupe a very capable track car, but even more importantly, a very unique car. After finishing the 02, Michael turned to a '88 E30 3 series sedan and armed it with full competition equipment and another of those V8s, now supercharged for 400 hp.
After building these two cars and getting bored with them rather quickly, Michael set out a far more ambitious plan, proving there's more fun in realizing the projects than using them afterwards. The new task was to be far more complex so that he could be sure the fun wouldn't end all too soon. The initial plan was to marry the M5 chassis with the CS body, but it soon turned out that Michael needed more than the two cars he had bought for the project, so he added to his collection another CS. It was a particularly interesting metallic green 3000 CS (in its heyday, owned by a famous German TV producer), but it was to finish its life as a backup source for the body shell parts. Neither of the donor E9s weren't in a concours shape, but then they didn't need to be, as they were to be stripped to bones anyway. As Michael was aiming for a 'factory new' quality of the finished product, he still had to buy some body parts. The good news was that BMW still offered them through the BMW Classic program, but the bad news was they didn't come cheap: the chromed front bumper was a 1100 USD expense, and some new lighting and chrome equipment came at around 10,000 dollars in total.
Spiraling costs often kill ambitious projects, but Michael remained cool-headed whenever necessary. To cut down on the expenses, he decided to pack his M5 and one of the E9s on a trailer and move them to Romania, a country around 1000 miles east of MKO's localization, to have the bodywork done there. After small fixes, the other E9 was good to go there on its own wheels, too. Outsourcing the handicraft to Eastern Europe is not unknown in Germany, France, or the UK, among the private restorers or even big classic car garages. The costs of labor in countries like Romania, Poland or Czech Republic can be as much as three to four times lower, but the skills of the local craftsmen can be, paradoxically, greater. While Westerners are spoiled with easy access to new parts and don't cultivate the art of repairing, the poorer mechanics from the Eastern Bloc have nurtured their skills that today pay off by breathing new life into old cars. The quality of the top workshops there can be so high that it's really hard to tell a renovated car from a factory new one. And Michael is happy that he could limit the costs of the whole project to around 165 000 USD. You can't run away from the fact that it's BMW i8 money, but for that you get a top-quality handmade one-off, which isn't far off the exclusivity of the works of Singer, Mechatronik, or Eagle costing many times more.
Renovating was one thing, but the most arduous task was to dress the M5 underpinnings with the CS body. All three of the cars had to be heavily adapted for their new roles. The M5 floorpan was stripped of its body and shortened around eight inches at the expense of passengers' rear room. The 1990's dashboard stayed, at least the part of it that fitted in the narrow CS's body. The latter, in turn, had to be extended here and there to house bigger components: front wheelarches are 2,5 inches wider, the rear ones four inches wider. Several of the body panels had to be made from scratch, but the quality of the work is so high that you just can't tell which ones were. One of those parts is the abnormally wide rear valance, which hides a pair of big silencers only to leave the four timeless exhaust pipes on display. The "best of BMW" compilation is complete with a set of 18" OEM E39 M5 wheels for clean and balanced looks of an unspoiled classic, spiced with some impressive, not disrupting modern details. It would have been so easy to ruin the perfect E9 looks, but somehow all this works, even with these wheels that, supposedly, had no right to look good here. The paint is not the usual BMW hue, either. In fact it comes from Porsche; specifically, a 996 GT2 that Michael used to own in the past.
After marrying the three BMWs into one unprecedented creation, it was sent back to Germany, where further work ensued. The project was far from finished. It took another seven months to install the drivetrain, the wire harness and thousands of other small components needed for the car to operate. You should know by now that Michael is pleased only with the very best, but he aims even higher than that. Before introducing the five-liter V8 into its new home, Michael took it apart and rebuilt it, for which the engine thanked returning full 432 hp on the MKO dyno. Given the altered dimensions and weight, he decided to retune the suspension as well. He turned over to KW for this job, the company well known in the tuning society. In fact, the German specialists have even a special department that caters for tuning professionals. With KW's help, Michael was able to find the optimum setup for the fully adjustable coil-over set the company usually offers to the M5. As the only change done to the stock ten-spoke wheels was switching their color from satin grey to light silver, the car rolls on the standard Michelin Pilot Sport tires, 245/40 ZR18 in the front and 275/35ZR18 in the rear. The M5's OEM brake system also remained intact, with 13.6-inch vented discs in the front and 12.9-inch rears having enough stopping power to cope with the lighter car. Indeed, weighting 3 686 lbs., the CS V8 is 330 lbs. lighter than the donor M5 and, as opposed to Michael's previous projects, the E9's bigger body allowed the construction to retain a near-perfect weight balance close to 50:50 per axle.
To find out how the car drives, we had no other option but to collect it from MKO's garage in Woerth an der Isar, a small quiet town about an hour's drive north from BMW's HQ in Munich. The local roads are still full of BMW cars, because just a stone's throw away, in Dingolfing, there is one of the biggest BMW manufacturing plants in the world. It's here that some versions of series 3 and 4 are made and all of the 5 and 6 series variants, and yes, M5 included. Coincidentally, the E39 was the first of the M5s to be born here, so it was symbolic for this car to receive its new incarnation here.
While approaching the MKO's creation, you gradually grow to see the surprising details on the spotless charming E9 body. You may be well bewildered by now, but the confusion reaches its peak when the chunky BMW key is turned only to reveal a polished, stabilized V8 rumble of the semi-dry sump double Vanos five-liter Bavarian heart. The surprise quickly turns into fascination, as the modern-yet-vintage-feeling motor beautifully builds on its power, of which it has huge reserves. If the original M30 straight-six engine was to be replaced, this could be done only with the motor of such quality. The shortened chassis didn't lose any of its perfect neutral balance, guaranteeing front-end grip to bite into the corners, and some playfulness of the rear axle when the driver is in the mood for it. With the M5 six-speed manual transmission and M Differential, the chassis has enough talent to become a true drift machine or a serious performance contender. The numbers help: The modern engine allows the car to reach 60 mph in around five seconds dead and cover a quarter mile in just over thirteen seconds. Definitely not something you would expect from a '60s classic impression, but it's not all about straight line performance only: the lighter weight and the spirit of the E9 make the driving a more straightforward experience, purer even than that of the E39.
It's surely a car easier to handle on a daily basis. What could be rather problematic in the CS makes perfect sense in what is virtually an E39 in disguise. The recent 5 series is not only more reliable and still easy and relatively cheap to maintain, but also so much more comfortable, from the perspective of today's needs. In the cabin with the E9's thin pillars and classic door design, the barely fitting M5 dashboard looks somewhat out of place, but offers some goodies like electric window lifts, effective air conditioning, or a Pioneer infotainment system with LCD display. For the seats, Michael chose a neutral timeless design of perfectly supportive Recaro buckets.
Meticulous and serious as Germans are, to register the car, Michael had to go through the special vehicle approval process in which MKO was recognized by the German authorities as a standalone car manufacturer. This answers the questions why there's no BMW branding on the car, as it's been replaced by the new MKO badges. On the other hand, it allowed the company to enter the market and offer the CS V8 as if it were any other car. Yes, you can really buy this one of the most prominent coupes in BMW's history underpinned by one of the finest performance cars. Michael is as willing to sell you the car you see here in the pictures as to build you a totally new one. For him, the job here is done. It's time to look for now challenges. Now, who's in for a restomodded '80s M 635 CSi?