Yeah, I know: a Bentley, an Ariel, an AMG Mercedes and a rebadged Holden aren’t typical group test competitors, but then this isn’t a typical group test. It’s not even really a ‘test’ in the traditional sense because surely there can’t be a winner.
These cars all have V8s but this isn’t a ‘greatest V8s of all time’ examination. Even a ‘greatest V8s on sale’ comparison would be stretching it. There are some great V8s whose makers couldn’t or wouldn’t pitch them in.
So what, then, is the excuse for lining up this quartet on the north side of the A3 Hindhead Tunnel on a Tuesday morning as a prelude to this feature?
A serious, state-of-the-nation assessment of the V8 engine’s future? Or maybe it’s because we fancied V8 accompaniment on a run through the longest road tunnel in the UK on our way to the south coast.
Our competitors go about the V8 thing rather differently. Bentley has made a turbocharged V8 for years, but only now has it tweaked this Audi-developed 4.0-litre two-turbo to put in the Bentley Continental GTC. It’s a prime example of downsizing; notable as much for its 25.9mpg and the cylinder deactivation as it is for its 500bhp.
Joining it in the blown corner is the Mercedes-Benz E63 AMG. AMG has hitherto had its charismatic 6.2-litre naturally aspirated V8 but has also downsized. And added turbos.
I’ve a soft spot for AMG V8s, not only because of how they sound but also because in the factory, engine development dyno rigs are hooked up to generators. So when an AMG engine is on the test bed, it’s producing electricity for the rest of the factory. There’s every change the Affalterbach worker are boiling their kettles courtest of a wrung-out V8.
We’re fans of the Arial Atom V8. We might have mentioned it in the past. It takes a certain mindset for a car company to decide a V8 is the right tool for powering a 550kg car. The Atom V8 makes 475bhp thanks to revving to the heavens. It has a flat-plane crank, too, so it doesn’t sound like a traditional eight.
Nothing in V8-land is quite so traditional as the engine installed in the Vauxhall Maloo. The Maloo might be an Australian wearing a British badge, but the engine powering it is pure V8 American tradition: the Chevy V8.
The latest Chevrolet LS3 motor displaces a heady 6.2 litres and can be considered the old stager here. It’s the archetypal V8. Ask a petrolhead to do a verbal impression of a V8 sound and the chances are it’ll sound like a Chevy. Lots of ‘blums’.
Its curious then that the Maloo is the quietest of the quartet at idle. The AMG has emits a purposeful crack on start-up. The Bentley emits a richer gurgle. The Atom can’t help but sound purposeful, because it is.
The Vauxhall makes only the lightest of burbles when it’s twisted into life, before settling to a muted idle. Maybe that’s because it’s sold all over the world and must meet strict regulations in parts of the US. Or maybe there isn’t much room for clever exhaust tuning. Listen carefully and the character is still there, and the car still rocks with a press of your right foot. Given the looks, its decidedly restrained.
I should point out that I’m not a great fan of ‘tunnel runs’. Definitely not ones where drivers come together with loud exhausts, louder whoops and a desire to listen to them along a road with an enclosed roof. It sets curtains twitching and provides easy pickings for Daily Mail headline writers. Its not coincidence the tunnel has average speed cameras.
To my ears, a pleasing engine note is best enjoyed when there’s no one around who’ll be bothered by it, like during our mid-week, mid-morning photo shoot. We’ve picked our moment so there’s enough ambient noise so nobody outside the bores will notice our passing. Yet it’s sufficiently lightly trafficked to pick the right moment to drop a couple of gears for purely scientific objective assessment. Which has the best-sounding V8?
In a hard-topped car, if you drop the windows and accelerate in a tunnel, you hear a bit of engine and a lot more wind. It takes a special car to make a bigger noise than the on-rushing breeze. It doesn’t take long to reach 70mph from 40mph in any of these four cars. That makes the enjoyment of noise a temporary experience. No sooner does it arrive, it’s has gone.
Let’s start with the Maloo. The big Vauxhall is leggily geared. Second reaches to the other side of 60mph. Sixth let you cruise at the legal limit at less than 2000rpm. Second or third is needed to make a substantial noise and even then it’s not that, well, substantial.
There’s some throat to it, lots of purpose and, as I find at the MIRA test track later, quite a lot of volume if you keep it nailed through the gears. On the road, its beauty lies in its delivery, not its sound. There’s ample torque from rest and it revs happily comfortably past its 6000rpm, 425bhp power peak. It’s a gem of an engine, but it doesn’t shout about it.
Bentley Continental GTC
Neither, at lower revs, does the Bentley. Crewe’s engineers have given the 4.0-litre V8 reserved attitude that suits the car. It wafts and strokes, shifting imperceptibly on the eight-speed auto. On throttle openings past 2750rpm, the note hardens. Clearly, acoustic engineers have been at work delivering a rich, deep and clear V8 grumble that stays to its redline. The beauty of this Bentley is that it’s a convertible. All the better for hearing it with.
The Mercedes has received similar levels of acoustic engineering, but it’s more obvious, more often. Both are unmuffled by their turbochargers. Neither whizzes, fizzes or whistles, but fine exhaust noise with a touch of induction urge.
The E63’s has a harder edge – and a more satisfying one than the Bentley’s, although the Bentley gives the impression that it’s shifting more air (which it isn’t, because the AMG is not just a bigger capacity but also makes 549bhp). For tunnels, the Bentley’s hoodless nature has the edge. Everywhere else, the Mercedes is more satisfying.
The Ariel is the exception. From the cockpit, where you’ll likely be wearing a helmet, there’s a lot of mechanical noise. From the outside, it’s a very different story. For immediacy and aggression, the Atom’s engine is in a league of one. By the time you’ve thought about giving it full urge in third gear, it’s time to back out again, if rampant wheelspin hasn’t already encouraged you to do so.
But what a machine. What an addiction. And when you can give it the lot, what a sound. Imagine a hoard of superbikes accelerating in sync and you’ll get the idea. The Atom is so spectacular that its engine doesn’t dominate the experience. The gearbox and its pneumatic shift are equally intoxicating. It steers and handles with aplomb, too, although it would be better still on grippier front tyres. Even its diddy paddle shifters are things of beauty.
That Bentley is a fine car, too. So rich in sound and performance is the V8 that the 6.0-litre W12 is now a way to mark out those who must spend as much money as is possible.
The rest of the Continental package is equally lovely. The GTC is a rare thing, a convertible unspoilt by the removal of the coupé’s roof. It later tipped MIRA’s scales at more than 2500kg. Bentley remains unafraid of excess and beefing up its chassis to retain rigidity.
Yet the GTC rides and steers admirably well, given its mass. If you have a Continental, you’ll likely have another car as well – in which case, for my money, you might as well have the convertible, for when nothing but open-air motoring will do.
Mercedes E63 AMG
The E63 is a lovely thing. I prefer the way a Jaguar XFR rides and steers but there’s appeal to the way the Mercedes does things. Chief among which is its engine. It has the most flamboyant motor in its class is why it, and not a BMW M5 or the Jaguar, appears here. If you want a the engine to dominates the experience, the Mercedes is the super-saloon of choice.
Vauxhall will import around 50 Maloos into the UK, although one suspects even this number won’t leave too many people disappointed. I love it, but it’s hard to see what you’d use it for. What surprised me about it is how tidily it drives.
There’s nothing shouty about the way the Maloo drives; the hydraulic steering is decently weighted, body control is fine, and it has a pleasingly neutral cornering stance if you get the front end tucked in under braking. The control weights are beefy, but that’s part of the charm.
What’s most remarkable about it is that its V8 isn’t its main event. The Chevy motor is reduced to tool. It’s an integral part of the experience but it’s not the blockbuster. The Maloo wouldn’t be right with any other engine, but the 6.2-litre unit neatly integrates itself into the package.
Is there a ‘best’ V8 in these? It’s impossible to say, in the same way there isn’t a ‘best’ car on the run from Hindhead down to the south coast, around nice roads with pretty views that the tunnel eliminates, because things are not like for like. The Bentley with the hood down is lovely on a coastal road in a way the Atom is differently lovely across twistier asphalt. Does the E63 better capture the essence of V8 than the Atom? It depends on your perception of V8.
In the traditional sense of offering power matched to lots of woofle, the Mercedes AMG is best. It’s probably my favourite V8 engine because it’s closest to what I understand a V8 to mean. Which car do I want the most? I’d take the Atom in a heartbeat.
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