Let’s start with the obvious, the CLA45 is ridiculously fast. Engage launch control in the dry and there’s barely a single horsepower wasted as the car hunkers down and fires you forward like few other cars full stop, let alone executive saloons. We didn’t have our timing gear with us, but we can fully believe that 4.0sec 0-62mph time.
Let’s face it, though, you’ll probably use launch control a handful of times to entertain friends or scare your mum. What really matters is how it behaves when you just put your foot down and accelerate. Whether you’re stationary or moving, there’s the briefest of hesitations before the A45 rockets forward ferociously, firing through its gears swiftly yet smoothly. There is, of course, a manual mode which is faithful to your inputs, but some may prefer the extra interaction the M2 Competition’s traditional manual gearbox brings.
But don’t expect the power to arrive all of a sudden like in some heavily turbocharged cars, this is an engine that thrives on revs. Peak power doesn’t arrive until a heady 6750rpm, while peak torque arrives at between 5000-5250rpm. Don’t think of this as a hardship, though, you’ll enjoy how the turbo wakes up at around 2000rpm, and how the power increases in a linear fashion all the way to the redline. Sure, it might not sound as good as the five-cylinder Audi RS3, but it’s still pretty good for a ‘mere’ four-cylinder and makes using all the revs pleasurable.
Now, if you’re reading this thinking the CLA 45 is a peaky monster that behaves like a bear with a sore head in traffic, prepare to be pleasantly surprised. Left in comfort mode, it feels no more recalcitrant than the regular CLA250 and is happy to trundle along quietly. Even with standard adaptive suspension, it is much stiffer than the regular CLA and feels a little firmer than the closely related AMG A45 hatchback, too.
Although it can be a little jarring over crumbling city roads, it's perfectly liveable once you’re up to speed on less craggy surfaces. Yes, you’ll feel expansion joints on the motorway and be aware of most bumps on a country road, but tight body control means it never gets bouncy or uncomfortable.
We’d hazard a guess and say that those interested in the CLA45 will enjoy the odd B road blast, so how does it behave? Well, although its steering isn’t exactly bristling with feedback, you do get a few messages from the front tyres once you’ve got a little bit of lock on. Vitally, though, the weight feels natural and it’s easy to place the CLA45 exactly where you want it on the road.
Even in comfort mode, body lean is minimal although you can happily ramp it up to sport mode without it wanting to bounce you off the road. Not only does this limit lean and help it feel more eager to turn in, it starts to alter the behaviour of the rear differential. Sport + and Race suspension settings are too stiff unless you’re on the smoothest of roads, but thankfully you can soften things off in the more extreme modes if you want.
Despite being front-wheel drive in normal driving, the back end always seems happy to receive plenty of power to help prevent the nose running wide. Push harder and you can really feel it dig in and help steer the car out of a bend. Slacken the electronic assistants and go past sport + and into race mode, and that clever rear differential becomes even more aggressive, allowing you to neutralise any mid-corner front tyre slip with a big dollop of power. Keep your right foot planted, and it’ll even slide oh-so-slightly in a jolly entertaining manner. An Audi RS3 is nowhere near as much fun as this, although it should be noted that the A45 is even more happy to wag its tail.
Then of course there’s drift mode. Although it doesn’t make the CLA 45 rear-wheel drive like the bigger AMG E63’s own drift mode does, it does help the car slide sideways easily when you accelerate hard and steer into a bend. Given its propensity to destroy tyres and its unsuitability for road use, though, it’s really an interesting gimmick and nothing more.