TG24: what's different about the new Ariel Atom 4?

The best thing about showing you details of the Ariel Atom is that nothing is hidden. Maybe that’s why Ariel felt they needed to go to such lengths when turning Atom 3 into Atom 4 – people would easily spot the common parts, so they’d better make an effort.

Just for the record, here’s a comprehensive list of the parts that have been carried over: the pedal box, the fuel cap, the steering wheel and top six inches of the steering column. Everything else in the 320bhp, 595kg lightweight is new, from the engine and chassis to the storage lockers and lights. But let’s start with…

Images: Mark Riccioni, John Wycherley, Richard Pardon

OK, not wholly new, as the Ohlins dampers were an option on the old Atom 3, and they are here too (Bilsteins are standard). But it’s not just the set-up of the dampers that’s new but the layout of the entire suspension, which now has different anchor points for the dampers and wishbones to help prevent squat and dive under acceleration and braking. 

Yes, the fully digital dash is all new and much easier to read with simple graphic for revs (on the right) and speed. But the more exciting stuff is the little blue knob you can see to the left. That’s a seven stage motorsport traction control system. There’s another knob on the right that controls the engine management through three levels of turbo boost, delivering 220bhp, 290bhp or 320bhp.  

Just look at it. Isn’t it beautiful? I’m chiefly referring to the machined aluminium upright. See how neatly the lockwires have been wrapped around the nuts, how carefully the cables have been tied? Shows the care and attention that goes into every aspect of the Atom.

Yes, I gave the game away earlier – the pedal box is one of the four parts that was carried over. But when pedals are this pretty, are you complaining? Guarantee you won’t be after you’ve used them. Clutch is lovely and reactions from both brake and accelerator are… vivid 

The most recognisably changed part of the Atom was done both for air intake and aerodynamic reasons. The airbox now integrates the rollover hoop, as when Ariel did some CAD work on the Atom, it showed that the external roll bar caused huge turbulence. Similarly, the engine couldn’t cope with all the air the larger aperture was trying to force in, causing air to spill. So now the opening is smaller. Safe to say the 2.0-litre doesn’t suffer from air starvation: 0-60mph is done in 2.8secs, with 100mph seen off in 6.8secs.  

Couple of things to mention here. Firstly, Ariel now fits different sized wheels front and rear (16s and 17s), giving the Atom a slight nose-down stance. Stance is good. Secondly, there’s an optional wheel upgrade available. Yep, you can have an Atom 4 with carbon rims. These are not them. Why? Because Ariel rightly predicted that we might take too many liberties with Portimao’s kerbs… 

We needed some skid shots of the Atom 4. This made me nervous. The old Atom 3, especially in supercharged guise, was many things, and some of those things were nervous, excitable and twitchy. Which made me a little concerned – just a little mind – what it was going to be like with a 320bhp turbocharged engine stabbing away at the back axle.

The answer is utterly brilliant. It feels far more planted, pliant and controlled beyond the limit than I ever thought it was possible for a rear-engined lightweight to be. Some very clever chassis design and suspension set-up work has gone on here.

This was the big one of course. Since the Atom 2 came along in 2003, Ariel has used Honda power, fitting it with a supercharger kit to really whiten those knuckles. But now Honda has let Ariel have the entire drivetrain from the current Civic Type R. Up to, but not including, the exhaust obviously. In addition to 320bhp, that means 310lb ft of torque and an utterly delightful six-speed manual gearbox. 

The new engine kick-started the whole Atom 4 project. It was bigger than the old unit, which meant the rear of the chassis had to be enlarged to accommodate it. Which got Ariel thinking: if a new rear end of the chassis was needed, why not a whole new chassis with thicker steel tubes? Why not rethink the suspension design? Why not design and develop the whole thing on CAD? And lastly…

…why not put it through an aerodynamics program as well? Yes, I’m using Mark Riccioni standing on it to imply downforce. OK, the Atom has no wings nor underbody diffusers, but it has been through a computational fluid dynamics program, to make sure it wouldn’t suddenly take off at 100-mph. In fact it’s better than that, the aero work done allows it to hit a max of 162mph.