The DeltaWing: The Look of Things To Come?


The rear structure of the car is a bit untidy for several reasons, the proof of concept use of the AMR P1 tub and the use of a production based engine instead of a bespoke racing derived engine.  A production based engine is not designed as a load bearing part of the chassis so a tubular trellis is needed to divert loads around the engine and gearbox. 
The back of the car also had to be quickly adapted to the new Elan Technologies powerplant after Nissan pulled out of the program.  The Elan Technologies team only had 10 days to mate their powerplant to the DeltaWing chassi prior to the start of the season at Sebring, a good reason for some of the workmanship you see. 
The rear suspension is very unusual in itself.  We think the way the DeltaWing works is that the rear is so heavily loaded by both weight distribution and aero load, that the small and lightly loaded front wheels are there merely to point the car whose center of rotation is very rearward.  Thus, the rear suspension is highly loaded. 
The suspension is designed as a pull rod configuration in bump and a push and pull rod in roll due to a low mounted rocker linkage that couples the opposite side shock in a turn.  The effet is that you get the damping of both rear shock absorbers in roll, very different thinking than typical!  The suspension appears to use conventional Penske dampers.

Here is the main rocker and the sorta pull rod upper linkage.  It is unremarkable and the magic stuff is down below.  Unfortunately a carbon buttress that the lower rocker is mounted to blocks the view.  We wish we could show you the push/pull rod suspension configuration as it is a pretty novel idea.

Here is the damper.  Unfortunately the tunnels are blocking a good view of the goods here.

We think that some of the suspension is bolted to this buttress that we think was missing from the car when it was Nissan powered.  You can see the top part of the rocker assembly that translates some motion to the opposite side of the car.  The rocker pivots at the bottom moved via the push rod. In bump motion is not translated from side to side but in roll it is so the damping of one shock in compression and the other in rebound are directly coupled.  It is sort of like a third shock design that some P cars use but without the third shock.  Of course the shocks must be valved specifically for this.

The front suspension is very unusual and very conventional at the same time.  The wheels are suspended by very short A arms configured for very little or perhaps even no negative camber gain.  There is not much thought to minimizing turning scrub in the geometry and the short side links have a lot of side scrub in bump.  We wonder if this doesnt matter much with the lightly loaded front end and skinny tires? 
Since we think the function of the front is to just point the mass of the car in the desired direction, the front does not need to gain mechanical grip in the normal sense of things (again a guess but we think this is the only way the car could possibly work).  The shocks are mounted very conventionally to the rear upright just like in the 60's! 
We wonder if that is a chamber for an inerter at the bottom of the Penske shock.  Since the front of the car is not tuned via roll resistance as that is not the way the car works (we think) there is no anti roll bar.  There is probably not much need for torsional stiffness either!  If the brake cooling duct looks strangely large we will explain why later.

The control arms pivot as close to the vehicle's center line as possible so side scrub and jacking can be kept to a minimum.  This sort of center pivoting arrangement means that the car must have some sort of weird center pick up steering rack to prevent horrid bump steer.  We would love to see it.

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