Build, Test, Drive, Repeat
Building the electric drivetrain into the eSLC.
It’s been a while since our last post, but that certainly doesn’t mean nothing has happened in the meantime. On the contrary, we have been busier than ever! Let us talk you through all the steps we have taken from the point that we actually started building the electric drivetrain into the eSLC.
After our car came back from the paintshop in November, we first had to start assembling the eSLC. Together with our partner SL Classics we initially started refitting all the parts that needed to go back on the car. Either complete new parts or restored original parts; from bumpers to lights, glass, weather seals, trim and chrome. At that point the eSLC started to look like a car again, although with a pretty peculiar stance. As you can see below, the SLC looked like a jumping lowrider when it came back to the headquarters in Genk.
Based on the 3D design and engineering, we could start mounting the complete electric drivetrain and all the custom parts we’ve designed and which were tailor-made for the eSLC. All kinds of special brackets, catchtanks, vacuumtank, VCU and PDU housings. Installing and fitting all these components went pretty smooth due to the meticulous preparations in pre-production 3D design phase. Most of the work was fitting both the battery packs in the front and in the rear section. Each pack weighs about 170 kilograms, so it’s not exactly easy to lift the packs in and out. So we first did all the fitment with the empty casings in order to be 100% accurate once the actual packs were installed. Both packs were not only connected to the high voltage harness, but also to a cooling loop. Our electric classic now has two separate cooling loops: one to cool (or heat) both battery packs and the other to cool all the electric components such as motor, inverter and charger.
Suspension and weight
All the major components, suspension, glass and trim were fitted, in order to start weighing the newly build vehicle. It was no surprise to us that the weight and weight distribution was quite different from the original 280 SLC we’ve started with. At the front side of the car we removed the complete engine and gearbox, a lot of old-school auxiliaries such as starter motor and water pump. Underneath the car the full exhaust vanished and at the rear the 90 liter fuel tank and fuel pump. After refitting all the electric components and new battery packs, we’ve restored considerably less weight in the front but added much additional weight in the rear. This turns out to be a blessing in disguise. Since the original car leans towards a 60/40 weight balance front to rear, our electric reincarnation is almost perfectly balanced with a 49/51 weight distribution at the moment of weighing the car. As soon as the full interior and other missing parts will be installed, we expect to be at exactly 50/50 and an overall weight of around 1520 kilograms. This is less than the original car!
Due to the changed weight balance, we needed to adjust the original suspension. Besides a full new set of Koni shocks, we have partnered with Koni specialist Frans Verbaas and Jordi Weckx from Apex Engineering to produce custom springs perfectly fitted for the new weight distribution.
And then the moment arrives that we could first fire up the car. Although “fire up” is not the best term in this context. It’s more like “energize it” for the first time!
Obviously still without any sound proofing or interior, only with the bare minimum of two seats and a steering wheel. After one and a half year of preparation, we must say it’s a victorious feeling to drive the electric iconic automobile we have started dreaming about many moons ago. And it drives great, what a special feeling to be in an electric car that looks the business! Initially only driving back and forth in the garage was already a milestone, afterwards some very short drives on restricted roads around our garage. But the actual full-pull testing started on the 1st of April.
Early April we loaded up the Monceau eSLC and headed to Aldenhoven Testing Center in Germany.
The Aldenhoven test track has quite some interesting test facilities, such as an oval track, Autobahn stretch, hill section, handling course and many other interesting tracks to test every possible characteristic that we need to know. We did all of them! From multiple hours of testing on the oval to hill climbing at 12 and 30%. Plus off course experiencing the new handling which improved considerably due to the better weight balance. We’ve also tested top speed -which is currently at around 160 km/h- and the expected range extrapolated from hours of testing on speeds of 80 km/h and 120 km/h on the oval track. The expected 250-300 kilometer range is very realistic. Accelaration is around 7,5 to 8 seconds with the current differential settings. Since the torque kicks in from the very start, the eSLC feels much faster and powerful than even the fastest petrol W107.
Now we are preparing for the actual launch of our first eSLC on the W107 platform. As we speak, the car is at the upholsterer for the full treatment of a new bespoke and tailor-made interior with high quality leathers and the 300 SL Gullwing checkered fabric. It will also receive custom wheels and some other surprises, but we will keep that for the actual launch.
Keep on following this website and our social channels and expect a stunningly beautiful Monceau eSLC in June 2021!
We will keep you posted in the meantime.