Pat Devereux20 November 2013

First drive: Nissan BladeGlider mule

Nissan recruits TG in the making of its bonkers DeltaWing-for-the-street concept…

Standing in the middle of a black lake of Tarmac somewhere in the Arizona desert is not the sort of place you might expect to have a motoring epiphany. But, unless I'm very much mistaken, that's what has just happened. I've been swapping between two Ariel Atoms for the past 30mins or so, just to make sure, but without a stopwatch to give me the empirical answers, I'm going to have to go with my gut.

And, despite everything I've ever learned or thought about lower, wider cars being better handling than taller, narrow ones - and I have the scars to prove my beliefs - the funny looking Atom with the narrow front end has handling that is not only equal to but probably better than the regular one.

I say probably better as it's only a suspicion at this point, a seat of the pants feeling that I've been trying to assimilate while still freaking out over driving what feels like a headless horse. A headless horse with knackered wheel bearings and a roll cage.

But it's important we get it right as there are a lot of people at Nissan who are waiting to hear what we think. Nissan high ups have already taken their pound of flesh from the two test mules, and the chassis teams have done their worst to them to see how they stack up under extreme load. Now it's time to get TG's opinions.

In reality the project has probably already been green lit, but that's not the story at the moment. There's still a paternal, project-deciding level of interest in our thoughts from TG's favourite chassis guru, Ben Bowlby, Nissan's Director of Motorsport Innovation and father of the Deltawing which started all this.

But before we get to Ben, a few details about how and why we are here. We all know about the Deltawing at Le Mans, the electric Zeod version that's going next year, and we've all seen the pictures of the bonkers BladeGlider concept car that uses the same narrow front track/rear weight bias, that's just been unveiled at the Tokyo Motor Show. But virtually no one has got behind the wheel of the racer - other than Top Gear's Ollie Marriage - and absolutely no one has driven the road version. Including the Nissan management.

So, before they nailed their colours to the narrow front track/rearward weight concept and went public with the BladeGlider, they insisted on having a go in a mule that could simulate the benefits of having such an unusual 30/70 front/rear weight layout. That's when they turned to Ben and gave him six weeks to come up with some kind of working technology prototype, to prove the concept could and would work just as well on the road as on the track. This is what we are driving today.

With no time to waste building something from the ground up, Ben had to get a weave on, fast. That's where the Atom came to the rescue. ‘We needed a road car that was based around the principles of a narrow front track, rearward weight distribution with rear-wheel drive,' says Bowlby. ‘So we took a donor vehicle [the Atom] that was a sporty and exciting and recognized enthusiast machine, and we said, OK, that's a very high standard. Let's apply the understanding that we have for the narrow track to that same vehicle.'

Having bought the two pristine Atoms, Ben then squirreled one of them away to his shed in Indy and set about creating the BladeGlider mule. The first thing he did was narrow the front suspension from 1.6 metres to a metre. Then he stretched the wheelbase by eight per cent. These two changes shifted front weight distribution from the standard car's 37 per cent down to 29 per cent, or almost exactly the same as the BladeGlider. To compensate for the loss of front roll stiffness, Ben's team then added an anti-roll bar to the back of the car, which added 10kg. And that was about it.

Other than the all-important changes to the wheels and tyres. The front tyre width was reduced by 40mm from a 195 to a 155 - it now runs tyres from a Smart - and the rear was increased by 40mm from a 205 to a 245. This is key to the whole Deltawing idea working - there is no net change in the amount of tyre in contact with the road, it's just redistributed relative to the weight shift. ‘That's a very, very important part of how this narrow track concept works,' says Bowlby. ‘It gives us this unique, consistent, and somehow coherent handling characteristic that's great fun to drive and makes you feel like a great driver.'

With the test mule built, Ben and his crew enlisted the help of NISMO driver Michael Krumm to shake it down. Krumm was skeptical to start with, unsure that it would translate from the track to the road. But after eight days pounding around Michelin's proving ground in South Carolina, he changed his tune when he took a look at the stopwatch.

‘We tried different tire compounds and constructions,' says Bowlby. ‘We tried different roll stiffnesses. We looked at the mass distribution in the car, and we got comfortable in brake distribution, wet weather running, bumps, lumps, auto test track. And we established that by making these changes to the weight distribution on the tyres, but without changing the overall weight of the car or the amount of tyre in contact with the road, we'd made a car that was appreciably faster.'

Appreciably in race terms can mean a fraction of a second. But not here. Try two seconds a lap on a 40 second total lap time. That's an instant five per cent improvement, which is huge. Just to ram home the results, Ben had cleverly engineered the mule so that the front track could be changed in 30mins from one metre to 1.3m and then the full 1.6m of the stock car. ‘

And the result? ‘It was fascinating because the actual pleasure of driving the car was enhanced as the two front tyres kept more and more of their load consistently through the corner [i.e. as the track got narrower and narrower],' he says. ‘I think that's really the secret of the car, that you have very little load transfer. So cornering doesn't take weight off the inside tire and move it to the outside tire at the front.'

The other part of the equation, of particular relevance to the BladeGlider, but clearly not the naked Atom test mule, is the narrow track also has huge aerodynamic benefits. The smaller front cross-section helps but so do the very narrow front tyres you can run with this set up. As they don't disrupt the air as much as regular-sized tyres the air moves faster over the rest of the car. The flow is upset when it hits the rear tyres, but that's OK as it helps drive the drag rearwards which gives much greater directional stability at high speed, in cross winds and when passing other vehicles.

Anyway, that's the science theory bit. Does it all work in practice? A quick drive of the standard Atom makes me think that the BladeGlider mule car hasn't got a hope. The regular Ariel is scalpel accurate, fibre optic fast and has endless grip. With no stopwatches on hand I try and benchmark speeds at which the car does certain manoeuvres - oversteer, braking, turn in, etc - around the course of cones. And then I jump in the mule and try and do the same thing.

First thing you notice in the mule is that you are sitting in the middle of the car instead of to one side, which is nice. The second thing you notice, thanks to the Atom's lack of bodywork, is that someone has stolen the front suspension and wheels. Which is disconcerting and odd. I'd have almost preferred it if the footwells had been paneled off to hide this, as it definitely affects how you initially feel about the car. Blame it on years of watching Reliant Robin crashes, but it takes a while to get used to.

Once you do, though, the Frankencar quickly starts making sense. In a straight line it doesn't feel any different. In hard cornering, instead of transferring all the weight to the outside wheel, it stays spread across both tyres, which together are wider - 310mm - than the standard Atom's 195mm tyre. So you have more grip and feel and you can pile on more power. And because you've got bigger rear tyres you can load them up harder and faster. I could fee it happening but the only problem I had was proving it.

I kept checking the speedo at the key moments to read off the speeds, but it was always almost exactly the same as the standard car. I tried swapping back and forth a couple of times but it kept happening. So I started to think that maybe the mule just felt faster, which was fine. But I was still a little disappointed. Until I mentioned it to Ben. ‘Ah,' he said. ‘I forgot to mention that. The speedo on the mule is seven percent slower because of the changes to the car.'

Bingo. Take two per cent off for my dodgy speed readings and I'd found where that magic five per cent extra speed everyone else had extracted had been hiding all along. Which brings us to where we came in: standing in the middle of a heat-hazed test track with a definite feeling that this narrow tracked Atom, the BladeGlider concept and any other narrow tracked Nissan vehicles are something that we want to know about - and drive - more. A lot more. Preferably on the road next. Particularly if the speedometer works properly...





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