Mark Hales on Technique: the Lotus Elise

A Lotus, tricky on the limit? Yes, really, if we're talking about the Mk1 Elise...

The object of these articles is hopefully less about the physics which govern a car's handling - there are many better qualified people who know more about that - and more an investigation based on practical experience. That said, there's no doubt that a different layout will inevitably offer the driver a different starting point; if the major masses - engine, transmission, fuel tank, driver etc - are in a different position, a similar control input may well elicit a different response. I still firmly believe that where the weight is, and how much there is of it, are the biggest determinants when it comes to a car's basic handling, and most of the stuff engineers do to suit a car for the track is intended to control that mass, or direct its influence somewhere else. Creating a balance on which the driver can rely is so very important - the top level bike racers talk about the "feeling" they have, which translated, means they feel confident to take extra speed into the corner because the bike won't do something unexpected.

Super Touring cars are relevant here, honest...

I finished the last one with a question; does the front of a front-engined car swing? The answer is a qualified yes, and it's one of the reasons why some Super Touring cars in the past featured weights just ahead of each front wheel. Think of it as rotation rather than a swing and I will delve in to that in more detail soon, but I'd like to continue our study of weight behind the driver and its effects. The wonderfully compliant Elite which was my last subject was from a time when Lotus weren't quite so reliant on a company parts bin for economic reasons, but ingenuity being the brand's DNA, such strictures probably helped shape the brilliantly simple Elise. One of the engineers who helped in the design once told me his approval from management was pretty simple. "Yes, you can make it" they said, "but you can't spend any money..."

That was more than two decades ago and the Lotus Elise is still with us, and remains a track day favourite for good reason. Colin Chapman's original mantra of light weight above all else also lived on in the company's DNA and the Elise will circulate all day and still be perfectly safe and legal to drive home on the public roads at the close of play. That is, as long as you haven't unintentionally modified it in the meantime... The Elise's handling is defined almost entirely by the location of its power unit and there was a tendency amongst my colleagues to describe the Elise as mid-engined, but given that the engine (and gearbox) is hung right across the back of the car, it's not, any more than the 911 is. And it is exactly that lump of mass right at the back which endows both with their distinctive handling balance. I read somewhere that the Elise possessed, "handling by God..." Well, we'll see about that, but rather than have a theological discussion, let's start instead with the plastic one, in its original Mk1 form, at Silverstone's Stowe corner which lies at the end of the Hangar straight.

On the road the Elise remains lovely...

Down that long length once more with the willing K-Series Rover rasping nicely through closely stacked ratios. Eye up the corner to the right, looking for the slight crest which hides the apex, then shuttle the gaze between there and the turn-in point which is becoming more familiar with experience. Time to brake, and immediately notice the firm pedal which doesn't have any servo assistance, sense the car's lighter overall weight which loses the energy of speed that much more easily. Snick it swiftly down to third gear and ease the wheel towards the turn, at the same time releasing the pressure on the brakes. The steering feels sharper than I was expecting given the weight in the rear, or maybe it's because of that strange little corkscrew which dips one rear corner, then lets it sit up again as the car begins to point in. I'm a little surprised in fact, just how well it does point. In fact it's a bit too damn sharp... The nose is pointing firmly towards the infield. Instinctively I'm piling on the opposite lock, but it doesn't seem to be working. It's as if a rear tyre has suddenly gone flat - damn. And I'd read about how the Lotus was possessed of the engineering answers...

Suitably smacked on the wrist by the track day organisers, not to mention my passenger, and lucky because the Elise pirouetted mainly within its own length - and of course because I remembered to get on the brakes once it was properly lost - I resolve to be a bit more careful as I turn in. This time, brake earlier and take a split second to let the car settle before I turn, the slightest of pauses which the passenger can't see and only the driver will feel as weight lifts from the front wheels. Then, ease the car towards the apex. The chassis settles, the steering settles, then writhes gently in response as we float through the corner, weight shuttling across the car and feeding back through unassisted steering. It's better this time. I feel more in charge of the process. Accelerate smoothly through the turn, enjoying the information coming via the wheel's rim and the gentle bobbing about which says the engine is behind rather than in front. Meanwhile, the slightest touch of reassuring understeer allows me to keep the foot buried hard all the way from apex to exit where the kerb comes sweeping smoothly to meet the nearside wheels.

... but having the engine so far back causes problems

Encouraged by the obvious benefits of such smooth technique and the lightweight agility of the Lotus, I feel confident enough to up the pace again. The last spill must have been a freak mix of circumstance... Down the straight we rush, eye up the apex, count to one then brake later and harder. Still no problem, pedal stays firm and the brakes bite nicely. Point the car in, taking care to maintain the measured approach and careful input which worked last time. The chassis corkscrew comes and goes, but the frequency has altered, the down and up seems to take a bit longer. There's still a bit of understeer to follow, so tread the right pedal and the Elise attacks the corner, bobbing and weaving more urgently now. All is still apparently well.

Then as we approach the apex, I can feel the back beginning to roll into gentle oversteer. I can get away with it surely, adding a touch of corrective lock which checks the slide but that makes the line wide. The Elise seems to be using up more road, edging ever wider... I've held the slide but I don't want it to get any bigger and yet we're running out of grey stuff. I read somewhere that you shouldn't lift off in one of these, not when you're going this quick. What the hell do you do then? Confused by the messages the car is sending, I feel like I've run out of options. Now there really is nothing for it but to cut the power.

In an instant, the back is slinging wide. Frantically I pile on the opposite lock, but again it seems to make no difference. The back end is on castors and it's on its way... Fortunately, there's still plenty of run-off area and I make my way back the pits, slightly bewildered because I thought I'd learnt my lesson. Didn't think I exactly asked for this particular incident. In the absence of any further inspiration I resolve simply to reduce the commitment again, especially now it's starting to rain... Down we go towards Stowe, adding a good few car lengths to the previous braking point. Squeeze the pedal gently... and... the fronts lock solid. No ABS here then! The steering freezes. By the time I have the wheels unlocked and rolling again, I'm past the turn in and I have no option but to get into Stowe completely off the power. Round comes the tail. Dammit, this is less than satisfying.

20 years later and Mark can still tell you all!

Another interview with the organizers and I try yet again, braking silly early and then easing into the corner with the fingertips but even at this pace the front begins to run wide. I back off again and because we are now going quite slowly, I catch the inevitable straying tail, but it's messy. The body slops back and there's a bit of a fishtail. The steering seems to have lost its feel and the car reverts to understeer yet again as I try to salvage the corner. This can't be right, surely. It's an Elise with divinely inspired handling. What on earth am I doing wrong?

The answer is, not very much. Elises, particularly early ones, could be extremely tricky on the limit, and in some cases almost undriveable with any kind of commitment when the surface beneath was slippery. The practical consequence is that the car is ever willing to suck you into a situation from which it is very difficult to recover - a fact which Lotus themselves acknowledged by the introduction of the wider and stiffer Mk2, which featured smaller front tyres in an effort to avoid setting off the back end. The Exige goes another way by shifting the characteristics beyond the point where they will trouble most people thanks to stiffer suspension and a degree of aerodynamic assist from the body and wing, and most important the extra grip from bigger wheels and sticky tyres.

But before anybody writes in, there's no doubt that the Elise family is extremely entertaining and any of them makes a fine track day car. The tricky bits are exactly what you need to hone your skills and the car has stamina which comes from the aforementioned light weight, and that allows you to do it for as long as you want, or at least until you hit something. Or the organisers decide you are a liability to front engined track users. The technique to be practised is to try and avoid provoking the thing. Keep it in balance as much as possible and try and avoid any situation where you will have to change your mind or do anything sudden.

Don't forget where some of those parts came from!

The dynamic problem is the same as always; when you lift off, mass is effectively transferred to the front tyres, at the same time reducing that which presses the rears to the track. In the Lotus, those rears are already dealing with a large lump of engine and gearbox which is a long way from the centre of the car - the original dumb-bell effect - and which is ever willing to swing around the car's central axis. Bear in mind too that when the tyres are within their limits and able to cope with it, the weight in the rear is what presses the back of the car to the ground and makes the front push on. The trap with cars like the Elise is the shift between the two. The upside is that the car is light and if the mass distribution is undeniably extreme, the amounts distributed are lesser and in theory easier to manage.

There are a great many specialists who have modified Elises over the years - not to mention Lotus themselves - and most have been successful in shifting the car's balance to suit a particular role, usually at the expense of tyre life. Hey, they're cheaper than mending the bodywork... It's also worth noting that the Rovers and MGs from which the Elise's motive parts were borrowed possessed a completely different handling balance. Obvious yes, but it does rather underline the point.

Previous stories:
Shifting the weight about
Moment of inertia

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