Earlier this week the DS Brand of Stellantis showed their latest concept the DS E-TENSE PERFORMANCE. Its purpose was to promote what they have learned in Formula E racing in what they will be offering from 2024 onward as the brand switches exclusively to electric vehicles.
One thing that caught our eye is the single nut rim, with a center hub reminiscent of what was offered initially on the original Citroën DS and ID up until 1965 when the company switched to 5 lug nut 15” rims, ending the use of the Michelin 165 SR 400 X tire.
Why was the single nut rim discontinued on the original DS and ID? Was it a matter of manufacturing cost? Safety? The fact that garages could better handle 5 lug nut rims? Probably not so much the the latter because the 5 lug nut rims only had a small square center hole which meant they could be put on modern rotational balancing machines (like rims from virtually every other make at the time).
We asked classic Citroën DS engineering specialist Ken Nelson for his opinion on the change. Ken says:
I’m sure back around early ’60s, Michelin realized that the DS single rims were basically outmoded by all the other wheels in the world going to multiple studs, and the 165-400 mm rims were outmoding themselves re size versus the “standard” SAE 15 inch rims.
If as a customer, you were in a place where Michelins weren’t readily available, and NO one else except some Italian brands used 400 mm rims, what could you do? Citroën and Michelin were locking themselves into a corner re availability around the globe. PLUS, the single-bolt hubs had to be hellishly expensive to manufacture compared to simple discs with studs.
They must have realized that the Traction 400 mm rims were a lot cheaper to make than the more difficult to form deep draw single-bolt ones. I’ve always been astonished at the considerable lack of cost/function comparisons that Citroen didn’t seem to be concerned about! The single-bolt wheel was the one item they most likely could have done without, considering the over-the-top production of that part compared to a stud plate like every other wheel but knockoff splined wire ones.
The single-bolt hub was in many ways an ingenious way of attaching a wheel, but economically it had to add a lot of cost to the car.
The DS brand press release for the E-TENSE PERFORMANCE states;
“Our goal is to apply the experience gained in Formula E and the expertise we draw from our international titles to a project that foreshadows the electric high performance of tomorrow. It is a laboratory which will be used to analyze the behavior of the components and to develop them with a view to future industrialization.”
So in keeping with the Formula E single nut wheel hub, the designers seem to have hearkened back to a road-going means to do the same but applying it to stylish 21” avant-garde rims with more than passing resemblance to the single nut hub introduced on the DS in 1955.
Electrically the E-TENSE PERFORMANCE sports two motors totaling 600 kW or 815 hp and a torque… of 8,000 Nm! The front engine has a power of 250 kW while its rear counterpart reaches 350 kW. DS claim this combination is capable of reaching an unprecedented regeneration capacity of 600 kW, which should largely spare the traditional braking system.
Its carbon shell accommodates undercarriages similar to those of a Formula E to ensure efficient and safe behavior in all conditions. This is necessary to cope with the surge of power and torque of the motors.
Bucket seats and the steering wheel are also carried over from a Formula E.
To power everything, the DS E-TENSE PERFORMANCE counts on centrally positioned a battery specially developed for it. Its envelope made of carbon and aluminum hides an innovative chemistry, Quartz EV Fluid, developed in collaboration with Saft, a subsidiary of Total Energies.
For illumination and visual impact, the design of the light signature of the vehicle has daytime running lights of 800 LEDS!
With the DS E-TENSE PERFORMANCE, the brand intends to find solutions to lower costs, make components easier to manufacture and consider applications in series models. The next generations of the E-TENSE range will benefit from these developments,” confirms Thomas Chevaucher, Director of DS PERFORMANCE.
The prototype begins a development phase with the experience and input of two Formula E drivers, Jean-Éric Vergne and António Félix da Costa.