Lotus SID

Project-SID-Esprit.jpg

Lotus was pretty much the only big-time British sports car manufacturer, until McLaren came onto the scene and made Lotus look like McLaren Light. I find it interesting that a number of manufacturers applied their abilities to recreate pretty much this exact car, albeit only either as a prototype or limited-production model.

The SID—"Structures, Isolation and Dynamics"—prototype, one of the most advanced prototype cars made in the '90s. The original Autocar review of the car by David Vivian has a number of eye-opening passages, but this one is my favourite: "But it's on the fast and bumpy roads of Norfolk…that the true, bludgeoning significance of its technology hits home. It's possible to forget about the rough engine, recalcitrant gearchange, cramped driving position and tatty, research-car cabin. What shines through like a halogen beacon is the sublime effortlessness of it all."

  • So wait, what did Lotus engineers manage to pack under its largely Esprit-like bodywork? 
  • Turbocharged V6 engine and 5-speed gearbox from the MG Metro 6R4 Group B car
  • Fully-removable bodywork with a full composite monocoque underneath
  • Steel subframes for suspension components (double wishbone) but with electro-hydraulic actuators instead of springs and shocks
  • Rear suspension actuator that gives the car active rear steering
  • Active front steering
  • Active engine mounts
  • Active braking
  • …and four-wheel drive

And you thought the Nissan MID4, Ford RS200, Lancia Delta S4 Stradale, Lamborghini Countach Evoluzione, and Panther Solo were some of the only mid-engined, all-wheel-drive cars from that era. 

In period, Lotus itself probably believed that the "next Esprit!" would have entered production using much of the tech found in the SID; I mean, here's a car that was capable of leaning into corners, like a motorcycle! Finally, the Citroën Xantia Activa would have had some competition on the slalom…

On the lumpy and patched back straight at 90mph, a tough ride test for a luxury saloon, SID obliterated the contours at the expense of neither harshness not float. And on the straight at 60 mph, a violent right-left-right flick to simulate an emergency lane change gave a g-force range of plus 1g to minus 1g, all within about half a second. Same streaming wet surface, but still the same ferocious turn-in, grip and neutrality.
— Bob Murray, Autocar September 1992