Mercedes-Benz SL-Class vs Porsche 911

What's the difference?

The SL's overall score is somewhat skewed by everyday concerns, and rules are rules - an average punter will find the price of this car somewhat confusing and the devil-may-care attitude to fuel consumption bewildering.

If neither of these things are a problem, then the SL63 makes plenty of - well, not sense, because it's not a particularly clever or considered car - but it fills a niche that not so long ago we all thought would go the way of the dodo.

The fact it sells so few examples is betrayed by some of the cabin amenities and the fact that Mercedes hasn't put much effort into reducing the car's weight to improve its consumption or sharpen up the handling.

The fact it still exists at all is pretty damn cool, though, and for certain people an SL63 purchase is the culmination of a lot of hard work.

If it is your dream car, the SL63 won't disappoint. Everyone who rode with me said it was mightily impressive, but you've got to really want it. When you're not far off buying a Ferrari California T or Aston Martin V12 Vantage S for the money, you'll need a real yearning for the three-pointed star to go this way. And if you do, good luck to you - you've probably worked quite hard to get here.

The more things change, the more they stay the same. The t-hybrid might be an entirely new propulsion system for the 911, but the net result is unchanged – power, poise and performance on tap.

Note: CarsGuide attended this event as a guest of the manufacturer, with travel, accommodation and meals provided.

The SL has always been completely unapologetic about its size and seems to be designed to accentuate rather than hide its length and width. The long bonnet screams power and prestige, and get out of my way, and is reminiscent of the little-loved McLaren SLR project of some years ago.

The size of the Mercedes logo on the huge front grille leaves you in little doubt about the brand of car that’s about to pass you at speed and some might say (okay, I would) that its large surface area is a little vulgar.

Like the SLR, the design doesn't seem to have a particularly cohesive strategy, with a number of Mercedes elements from around the traps that climb over each other. Roof up it looks awkward because of the gigantic posterior while with the roof down it looks overly long and, again, tail-heavy.

Folding hardtops are notoriously cumbersome and need a lot of room to hide them, but the silent operation is something to behold.

Elements that are worth deleting if possible are the dodgy 'Biturbo' badges. It's that kind of bling that gets people raising their little finger at you.

This facelift debuts a revolutionary exterior design that has completely reshaped the 911.

Just kidding. If it ain’t broke and all that. The front air vents and exhaust have changed, the former now an active intake system that deploys via vertical flaps, but elsewhere it’s largely evolution over revolution.

Instead, Porsche has focused most of the updates in then cabin. In here, you’ll find a new digital instrument panel, they’ve changed some of the levers and the steering wheel.

In true Porsche fashion, though, this new 911 mimics the older versions in that it's one of the more intuitive cabins you’ll ever sit in. Everything feels as though it’s exactly where it should be, and all feels entirely centred on the driver.

“Practicality” is about as relevant to this car as a code of ethics is to a drug dealer or a contract killer, because the SL63 buyer is hardly worried about cupholders and boot space. For what it's worth, there are four cupholders in the two-seater cabin (which might explain why owners aren't worried about their liquid carrying prospects) and a minimum boot space of 364 litres and a maximum - with roof up - of 504, which is actually not bad.

Cleverly, there's a little robot-operated luggage cover inside the deep boot that stops your gear from being crushed when the roof goes down.

There's also space in the long doors where you might secrete a bottle of wine that would get a NSW Premier fired if he thanks you for it, and a bin in the console to hide your phone.

This probably falls under the ‘next question, please’ umbrella, given that, while the Porsche 911 is known for a lot of things, vast acres of space with loads of practicality perks just ain’t a part of its portfolio.

The new 911 measures a not-insubstantial 4533mm in length, 1852mm width and around 1294mm in height, and it rides on a 2450mm wheelbase. Luggage space is a paltry 135 litres under the bonnet, plus whatever else you can fit in your pockets.

There’s seating for four, should you not like the people you’re squeezing back there very much, but really the 911 is best enjoyed as a two-seat proposition – which is why you can also delete the backseat, should you wish.

It also weighs a minimum 1595kg, or up to 1745kg, but Porsche says the hybrid tech only adds about 50kg to the total kerb weight.

Yikes. Perhaps I wasn’t paying close enough attention, because the Porsche 911 range now suddenly seems very expensive.

In fact, it inspired some research. Some 10 years ago, in 2015, the Porsche 911 range kicked off at around $208,000. Today, though, you’re looking at more like $280,500 for the entry-level 911, and if you want this bahn-storming Carrera GTS, you’re looking at more like, deep breath, $381,200, before on-road costs.

If you want four-wheel drive, a cabriolet roof, or both, the price climbs from there, with the GTS range topping out with the Carrera 4 GTS Cabriolet listing at $437,900.

Now in Germany’s defence, the Porsche has gotten progressively faster and more powerful over the years, and that’s true again with the T-Hybrid version, but we’ll come back to the tech stuff in a second.

Outside, it rides on staggered alloys (21 inch at the rear, 20 inch at the front), and there are standard matrix LED headlights, vertical-mounted active cooling flaps, and you can have it as a hard top, a Targa roof or as a full Cabriolet.

The biggest updates (apart from the driving stuff, of course, occur in the cabin, where the 911 has now push-button start, and introduces a new digital dashboard, which defaults as a digital version of the old analogue setup. The screen is 12.6 inches, and there’s a second 10.9-inch screen in the centre cabin which does your phone streaming.

There’s also a BOSE Surround Sound System, 14-way adjustable comfort seats, and digital radio.

The SL63 is powered by Mercedes’ increasingly famous V8, with two turbos along for the ride to add oomph and cut the car's famous consumption, at least slightly. The 5.5-litre unit produces a massive 430kW and a scarcely believable 900Nm of torque.

All of that heads rearward via a seven-speed dual-clutch transmission that helps sling the 4.6m, 1848kg machine to 100km/h in 4.1 seconds.

A new (or at least, massively altered) 3.6-litre petrol engine has been developed for this T-Hybrid, which combines with two electric motors to produce a total 398kW and 610Nm. It’s only available with Porsche’s very good eight-speed Porsche Doppelkupplung (PDK) automatic, largely because the brand admits it would be… well… unpleasant to drive as a manual.

Now, there is lots of magic at work here, and I don’t want to bore you, but the Porsche setup sees a lightweight 1.9kWh battery placed basically in the middle of the front axle, and a 12-volt battery now behind the front seat. Then, a tiny e-motor lives as part of the gearbox (it’s just 55mm long) and delivers up to 150Nm at low speeds to supplement the petrol engine.

It’s joined by what Porsche calls an “electric exhaust gas turbocharger”, which essentially removes the spooling time from the turbo, delivering instant power.

The aim of the game here is excitement, not efficiency, and the launch-control-aided spring to 100km/h takes just 3.0 seconds. And it somehow feels, and sounds, faster.

The latter being important, with Porsche aware that if the new powertrain didn’t sound good, "nobody would like it”.

Much as is the case with the price, there's no real way to soften the blow here - the SL63 drinks like a footballer on Mad Monday, except it does it every day. The official combined cycle figure of 10.2L/100km is quite easy to double, as we did, averaging 21L/100km in mostly flowing suburban traffic. In the car’s defence, the accelerator pedal spent a good deal of time near the firewall.

The SL does have stop-start to help reduce its considerable environmental impact.

Porsche in Australia is yet to lock in local fuel use for the Carrera GTS T-Hybrid, but international testing has it at 10.5-10.7L/100km, C02 emissions of between 239-244g/km. 

Those aren’t exactly Toyota Prius numbers. But again, that was never Porsche’s intention. The electric power on offer here is intended to improve acceleration, not fuel use.

It’s fitted with a 63-litre fuel tank, which should deliver a driving range of around 600km per tank.

There are a number of impressive things about the way the SL drives. Firstly, astronauts will be familiar with the galactic thrust of the V8. It seems endless, seamless and ready to sling the big coupe into the outer atmosphere. Few engines of any kind can match the relentless go on offer in the SL and much of the credit should go to the seven-speed twin-clutch transmission.

When you jump on the brakes and shift down, the exhaust keeps the show going with angry crackles and pops.

Containing a torque figure like the twin-turbo V8's requires a lot of electro-trickery to stop you from being launched off the road. The great thing about all that stuff is that it works unobtrusively and smoothly.

Mashing the carpet in an SL without traction control would create much sound and smoke but little forward progress, such is the twist on tap. The SL has a range of modes from full-nanny (which is meant to keep you on the slippery Alpine road you've chosen to get you to some Swiss ski resort) while turning the dial all the way around to Race loosens the bonds.

It's in this mode you'll have the most fun and it does seem that the intermediate settings are a bit of a waste of time. Race mode does little to diminish the amazing ride quality provided by the active suspension setup, but relaxes the reins on the huge rear tyres. Exiting roundabouts is suddenly a huge laugh, with the tail cheerfully breaking traction and the two-mode exhaust thundering in a most pleasant way.

Better still is that when you jump on the brakes and shift down, the exhaust keeps the show going with angry crackles and pops, with more on the way when you lift off. There's little to match the aural pleasures of a properly tuned V8 and Mercedes has resisted the temptation to quieten it down on the outside and generate a fake noise for the inside. Although that would be stupid in a convertible, if you think about it.

The SL63, despite its AMG badge, isn't about all-out handling, of course. The Ferrari California would definitely show it how it’s done on a winding country road. The SL is more about flow, building momentum and rarely shifting down to second gear. The monstrous torque is enough to keep things rolling but should you wish for a bit more of the exhaust bellow, second is there for the taking.

Hustling the big convertible feels wrong, not because it can't do it, but because it's not really what it's for. Having said that, it offers a kind of fun that nothing else on Earth will provide, not even a Bentley GTC.

With the roof up, the SL63 is a quiet place but not remarkably so. The huge sticky tyres do the cabin's hush no favours, with an annoying roar on a wider range of surfaces than you might expect.

Roof down, it's hardly a paragon of virtue. A lot of wind noise reaches the cabin, even well below the huge speeds the SL can reach. So if you want to talk, it's windows up you'll need to deploy the mesh screen that bridges the roll hoops.

Porsche did just about the Porschiest thing to ever Porsche in launching the 911 Carrera GTS T-Hybrid, in that we piled into cars in Melbourne, drove the many, many hours (well, it feels that long, at least) to the Phillip Island race circuit, beat the hell out of the cars on track and on the drag strip for several hours, then trundled back out on the road and drove them back to Melbourne.

The subliminal messaging here is pretty clear. This new 911 might have a new powertrain, but it can still deliver the road-track-road experience without breaking a sweat — or, more importantly, without breaking any expensive bits.

So let’s do this in order, shall we? On the road, this new 911 is every bit as sweet as it has ever been. Comfortable, quiet enough when you want it to be, and — save some road noise from those big wheels – quiet enough to let you forget you're driving something with one of Peter Dutton’s nuclear reactors hidden beneath its svelte metal work.

Mind you, that T-Hybrid powertrain will happily remind you of its presence every time you press the accelerator in anger, the exhaust erupting into life and the 911 genuinely rocketing into the future, but stay gentle with your inputs and this hybrid 911 is a genuinely comfortable, genuinely liveable daily driver.

Its split personality appears when you rumble out onto a race track though, where you quickly discover the electrified, and electrifying, Porsche is properly, properly rapid, both in a straight line or around Phillip Island’s fast and flowing circuit.

It’s so rapid, in fact, that it feels most closely related to a performance EV, like the Taycan. Of course it is louder and more engaging, but that’s the best way I can think of to describe the instant power on offer here. There’s no ICE-like lags or lumps in the way that 398kW and 610Nm finds its way to the tyres and into the tarmac. Instead it’s just this constant, savage flow of power that never seems to let up.

Porsche says this new powertrain is about 50kg heavier, but you’d need to be plugged into the race track like its the Matrix to ever feel it, with the T-Hybrid feeling lithe, grippy and athletic, aided by near-perfect steering, the best automatic gearbox in existence, and exactly zero roll through the body. In fact, the only thing that really moves when cornering hard in this new 911 is the driver, and I genuinely got out after several laps with a sore neck from trying to stay vertical.

Downsides? Well, it’s faster in a straight line (it will be some 7.0m further down the road after 2.5sec when compared to the older GTS) and faster around corners (8.7sec faster around the Nurburgring than its predecessor), but there’s something delightfully analogue about the outgoing car, which also manages to feel more aggressive under heavy acceleration, too, owing to the little ebbs and flows of power, and after driving both back-to-back, I still can’t decide which one I like more.

This 911 arrives without an avalanche of active safety kit, but the key stuff is covered. There are airbags up front for the driver and passenger, side impact protection including thorax and curtain airbags, auto emergency braking (AEB) with pedestrian detection, a surround-view camera with parking lines, lane change assist, lane keeping assist, adaptive cruise control and a driver fatigue monitor.

The SL63 is covered by Mercedes' three-year/unlimited kilometre warranty. And, er, that's it.

The 911 Carrera GTS is covered by a pretty underwhelming three-year, unlimited-kilometre warranty, with servicing required every 12 months or 15,000kms. We don’t have the hybrid service pricing yet, but as guide, the last 911 split the services into minor and major, and charged either $785 or $1285 for each.