SID's too sexy for his clothes
Never mind the Esprit-style apparel - what's underneath will rewrite all supercar rules, says David Vivian after driving 'SID' on the road.
Jaguar XJ220, Bugatti EB110, McLaren F1 and Yamaha OX99: the strangest and most fabulous objects in the automotive firmament; the black holes of the supercar cosmos. Until a few years ago they didn't exist, but we now know that from their gravitational clutches no fertile imagination can escape and behind their event horizons cash is crushed out of existence. So the question is this: what makes these cars worth in the region of half a million quid a piece?
Dunno. No matter how much I juggle with advanced aerodynamics and lightweight materials, exotic seating arrangements and outrageous styling, 500 horses and race car suspension, 200mph-plus top speed and time-warp acceleration, large (Jaguar XJ220 and Bugatti EB110) and small (McLaren F1 and Yamaha OX99), none of the hyper-priced newcomers has furnished me with anything that suggests it will significantly improve the state of the art as defined by Porsche's 1988 959. At least not by the thick end of £300,000.
A few people have shelled out £415,000 or so for XJ220s, but some have sold on their deposits, and Yamaha has been forced to put its project on hold through lack of firm orders. Perhaps the buyers decided that a Lamborghini Diablo was what they wanted after all. But perhaps they're just waiting for the supercar that really rewrites the rules to show up, the one that doesn't just expand the performance envelope but changes its shape.
Perhaps the people with half a million at their disposal would never consider buying anything as commonplace as a Lotus, but if any one of them could persuade the Norwhich-based car maker to part with the one and only SID - Structures, Isolation and Dynamics - research car they would own a car with technology far in advance of anything currently available, some truly new and exciting moves, a unique feel that once experienced is never forgotten and simply the best ride there has ever been. No one will, of course. SID, an ever-evolving testbed, isn't for sale. What it has demonstrated with breathtaking clarity at Lotus Hethel track is that the art of the possible and the art of the probable are separated by a few brushstrokes but those brushstrokes might be separated by a few years.
Driving it on the track last September, Bob Murray explored the sort of dynamic behaviour previously incarcerated by the limits of conventional chassis theory. After driving it on the road, my advice to anyone with a notional half million is to hang on to it. Lotus's managing director, Adrian Palmer, says 1995's new Esprit will be technology led and "go straight to the top of next century's supercar league". SID holds most, if not all, of the clues. The confusing thing is that it looks a lot like the current Esprit - but this could hardly be more misleading. The modified Esprit body - note the lower front spoiler and skirt, deep bonnet scoop, blocked-off three-quarter panels, elongated tail and special wheels - was used for convenience and not as a stylistic signpost to the future.
Underneath (and the major body panels are detachable so you can have a good look), SID makes you gulp. For a start, it has full active suspension - no springs, no dampers, no anti-roll bars, just a collection of computer-controlled electro-hydraulic actuators that control the body's movement and attitude in a 'closed loop', irrespective of road surface or cornering speed.
Moreover, an additional rear actuator translates various parameters (steering wheel angle, yaw rate and lateral acceleration) into active control of the rear steering angle - and it has a huge 15 degrees to play with. Add four-wheel drive and the combination of hardware looks electrifying, even on paper. In Lotus's hands, you suspect the result is going to be even better than that. And SID eschews the Esprit's backbone chassis for a monocoque made of glass-fibre and epoxy sandwiching Nomex honeycomb. Light 'n' stiff is always the aim but this stuff is exceptional (158kg, 16,000Nm/deg) and provides a superbly rigid platform for research purposes. The options, here, are startling. Steel subframes support the double wishbone suspension, mounted Elan-style on 'rafts' for optimum control of longitudinal motion. Suspension loads can be borne either by the body - via bushes between the powertrain and subframes - or, like F1 cars, by using the reinforced drivetrain as stressed part of the structure. In this case, the bushes between the subframes and the monocoque can be made very soft.
After all this ('all' is a relative term, here, sonce Lotus is also working on active front steering, active four-wheel drive, active engine mounts, active engine valves and active braking), the Metro 6R4 V6 engine and five-speed gearbox are a conspicuous letdown, not so much because of their pedigree but because, during my drive, one is misfiring and the other baulking. Besides, the claimed 300bhp feels decidedly optimistic. Project chief Richard Hurdwell, sitting in the passenger seat, doesn't seem too moved to make excuses for a drivetrain that was only ever intended to move SID sufficiently fast to explore the potential of its structure and chassis. And it certainly does that, even if the regular Esprit Turbo SE I just drove round the Hethel circuit felt comfortably quicker down the straights and considerably more refined.
Streaking down the straights isn't a priority in SID, anyway. Hurdwell uses the wide open spaces to demonstrate the full repertoire of active options - all implemented from the slim computer sitting on his lap that's plugged into the Lotus's central nervous system. The show embraces the usual active suspension tricks - no-roll cornering, negative-roll cornering (where the car leans into the bend motorcycle-style: weird) and the negative-dive braking (where the nose actually lifts when you stand on the anchors: even weirder).
Still more dramatic, however, is the way the fundamental character of the handling can be altered. Moving the effective yaw centre forwards and back, for example, has an astonishing influence on the way the car responds to the steering, changing turn-in - optimally quick and precise and married to unparalleled bite - from hair-trigger, where just the act of breathing seems to change direction, to never-ending, where the front wheels seem forever to be peeling away from the apex. Alternatively, you can dial in a degree of body roll to 'normalise' the feel of the handling. I'm reminded of BMW's active rear axle kinematics on an 850i, the impression that however injudicious your entry speed or steering inputs, the chassis is filtering out the 'idiot factor', only allowing itself to act within prescribed limits. With SID the limits are so high that it's almost impossible to get it to misbehave.
Hethel is fine for probing such things and establishing SID's extraordinary baseline abilities: it's amazing stability, traction and grip, unparalleled steering speed and bite, uncannily flat and disturbance-free ride and unprecedented adaptability. For these attributes alone, it blows all known references out of the frame. But it's on the fast and bumpy roads of Norfolk - set up just as Lotus suspension guru John Miles likes it (with a tad more understeer than most of the development drivers prefer) - 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.
This isn't 'effortless' in the way a Lexus or XJS is effortless. It has little to do with refinement. Ni, it's the way SID takes all the extraneous behaviour - all the little fidgets, squirms, structure-born shudders and sundry expressions of strain and imbalance - clean out of the driving experience. What's left is frighteningly pure and direct; like being given a glass of spakling Perrier after years of drinking ditch water. So stiff is the structure you're harnessed into and so mathematically correct the actions of its chassis that the sense of oneness is almost overwhelming. You think you know what accurate, communicative steering is, but SID shows you that you don't. It demonstrates that writhing, gratuitous feedback only blurs the picture. Once you've got rid of the information that doesn't contribute to feel, there isn't much left. But what there is feels wonderfully right. A Caterham's helm seems crude, grubby and corrupted after this. Look at it another way. SID is the automotive equivalent of an infinitely powerful and distortionless amplifier: everything it does is accomplished with an iron grip. Yet there's great finesse and focus, too: it resolves dynamic nuances other cars only hint at. ANd it resolves them whatever the road surface.
It's the same with the ride. With it's comfortable in the conventioanl sense is impossible to answer. you wouldn't call it supple or cosseting and yet it's flatter and less ruffled than anything you've experienced and phenomenally consistent. As such, it ceases to be an issue - other than being one less thing to worry about when you're going hard on a bad road.
And if you think that makes SID the best supercar I've ever driven (XJ220 included), you'd be right. What excites me is that the best Lotus is yet to come, and you'll be able to buy it.