Porsche Cayenne vs Audi RS Q8

What's the difference?

Of all the super SUVs I've piloted, the Porsche Cayenne Turbo GT is the best all-rounder in terms of performance, comfort, cabin technology and style.

As a family car it's roomy, practical and easy to use and drive daily.

As a performance car the Turbo GT is stupidly quick, with the agility of a sports car. Sure, a 911 would leave it behind on a twisty race track, but this SUV is close to having that sportscar experience and keeping your family, as well.

The Audi RS Q8 Performance is a lot - of everything. It offers lots of power, lots of performance, lots of space and lots of luxury. But it’s also a lot of money, and at more than $250k it’s not going to be on everyone’s shopping list. It’s a very niche proposition for a small group of buyers. For those select few, those who want a lot of everything and who crave the ultimate of whatever product they’re buying, then the RS Q8 Performance is going to be a very tempting proposition - even if they never set any lap record in it.

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

This might be a personal thing but to me nearly all Porsches look better from the back than the front.

It's the wide stance and powerful haunches, the hunkered down suction-capped-to-the-road look that does it for me and the Cayenne Turbo GT, despite being an SUV, passes this important Porsche checklist item.

The GT aero kit only serves to make this SUV look more of a beast, and the gold-bronze looking satin Neodyne wheels are a Porsche theme that I've not always been a fan of, but I get the historic connection.

If only the Turbo GT could look a little less like other Cayennes from the front. This is the king of the SUV range and despite the apron and bumper already being exclusive to this model, there should be more.

Vents in the wheel arches, carbon bonnet with nostrils GT3-style perhaps? Or is that going too far? If you do want something more lairy then there's always the Urus.

The Cayenne Turbo GT's cabin is stunning in its plushness and modern surprises such as the passenger display, the hoodless instrument digital cluster, the lashings of Race-Tex upholstery everywhere. It's perfectly Porsche. High-performance meets high-end.

It's also highly practical. Let's talk about that.

We don’t refer to ‘facelifted’ cars for no reason, the RS Q8 Performance has a number of visual changes.

These include a new Audi ‘singleframe grille’ and new front bumper design, with a new Matt Carbon trim package available to highlight that.

There’s also a new rear bumper design as well as new digital daytime running lights at the front and digital OLED lights at the rear.

The unique forged alloy wheels are another design change, but also bring a functional element. Measuring 23 inches they do a good job of filling out the wheel arches and give the RS Q8 Performance a purposeful stance and good proportions. But they are also 5kg lighter per wheel than the 22-inch rims on the RS Q8, saving unsprung weight to help the ride and handling.

Inside, Audi hasn’t made any dramatic changes to the design, which is fine because the brand does some of the best cabins on the market in terms of look and feel.

What is new is an aluminium inlay and an optional RS interior design package which provides a unique finish to the seats, with contrasting stitching, for an additional $4100.

The Porsche Cayenne Turbo GT only makes one compromise on practicality and that's the removal of the middle seat in the back, which, with just two kids isn't used all the time but on average we might need it once a week for school mates and cousins.

Instead of a middle seat there is a shallow tray, which will fit a phone or in our case leaves and rocks found at the park.

So, yes, the Turbo GT is a four-seater only, but this is a spacious, large SUV with good head and legroom, wide-opening doors for easy entry and exit, and air suspension which can raise and lower the height for easy access.

Storage is excellent with enormous door pockets in the front and back and there are four cupholders.

There's a wireless phone charger in the front and two USB-C ports as well, plus two USB-C sockets in the back.

Four-zone climate control means the kids in the back can set their own temperatures. They also have heated seats.

I was disappointed to see there aren't sunshades for the rear windows - pretty vital in Australia where it feels like we're only about 50 metres away from the sun.

The Turbo GT's 576-litre boot just managed to fit our pram and a week's shopping, which is our minimum standard for living. Any more space is a bonus.

While it’s easy to get swept up in the power and speed of the RS Q8 Performance, it’s important to remember that it’s an SUV and it needs to offer ‘utility’ as well as ‘sports’. 

With that in mind, the front seat occupants are well looked after with supportive and comfortable sports seats, with a good amount of small item storage spaces. 

The rear seats are surprisingly comfortable, despite the sloping roofline of this ‘coupe-style’ SUV. Audi has cut recesses into the ceiling to create more headroom, so it will be fine for anyone under six-foot tall. Despite there being five seat belts, this is realistically more of a four-seater for adults, although three smaller kids could squeeze across the back.

There’s also a pair of cupholders, two USB-C ports, a 12-volt outlet and your own climate controls for the rear passengers.

As for the boot, again it loses some volume because it’s not a wagon-style SUV, but there’s still a decent, square floor space with a claimed 605 litres of capacity.

So, overall the Q8 obviously isn’t the most practical version of an SUV, but it does well given its focus on style.

Audi updated the Q8 range earlier this year, with refreshed looks after seven years on sale and a plug-in hybrid powertrain to cater for new demand.

A new RS Q8 is coming later in the year, but the RS Q8 Performance has arrived first to make a bigger impact. It naturally gets a performance boost, but there are some other extras beyond more kilowatts.

These include RS ceramic brakes, lightweight 23-inch forged alloy wheels, Pirelli P-Zero tyres, unique aluminium inlays and a special RS layout for the digital instrument display.

Which is good, because the RS Q8 Performance costs nearly $25k more than the ‘standard’ RS Q8, priced from $255,800 plus on-road costs.

Luckily for a car costing a quarter of a million bucks, there’s also plenty of luxuries too, including Nappa leather upholstery, four-zone climate control and a 17-speaker 730-watt Bang & Olufsen sound system, amongst others.

When you compare it to its rivals on performance terms, in particular the Urus and Cayenne Turbo, the $250k asking price doesn’t exactly look ‘cheap’ but it is good value in comparison.

The Audi is a touch pricier than the BMW X6 M Performance at $250,900, but quite a bit more affordable than the Mercedes-AMG GLE63 S Coupe at $268,900.

As a middle-aged parent with two children, a Porsche that I don't have to crawl into and out of like a cubby house is a great thing.

What's even better is that this ‘easy access' Porsche is every bit as brutally powerful and fast as the quintessentially ‘pure' Porsche, the 911. Actually, it's more powerful and faster.

The Turbo GT's twin-turbo 4.0-litre V8 petrol engine makes 485kW and 850Nm with drive going through an eight-speed transmission to all four wheels.

In comparison, a Porsche 911 GT3 RS, arguably the most brutal and anti-social 911, has 386kW/485Nm.

I haven't made a mistake. Those are the real numbers. And it's only when you step on the accelerator in the Cayenne Turbo GT, and it feels like somebody's sat down on your chest, that you realise what a big deal this is.

That is such a colossal amount of oomph that this 2.2-tonne family SUV can accelerate from 0-100km/h in 3.3 seconds.

The 911 GT3 RS can do it in 3.2 and it has a roll cage and a fixed rear wing the size of a bedroom door.

And yes, we're now coming into a digital age where Teslas and other electric SUVs are quick, too, but can they go around corners like a Porsche Cayenne Turbo GT?

Do they have the same rumble and roar as a twin-turbo V8 that's terrifying and enticing at the same time.

The correct answer is, absolutely not.

This is the latest iteration of Audi’s twin-turbo 4.0-litre V8 petrol engine - and it’s a beauty.

While this engine is used in a variety of models, for the RS Q8 Performance Audi has taken power to 471kW with 850Nm of torque, which, as mentioned earlier, makes it the most powerful internal combustion engine Audi has ever offered in a production car.

That’s also a big boost over the previous RS Q8, which managed 441kW/800Nm, and is only just shy of the 485kW/850Nm offered by its ‘cousin’, the Porsche Cayenne Turbo GT.

Audi claims that the RS Q8 Performance will launch 0-100km/h in just 3.6 seconds and keep going to an electronically limited top speed of 250km/h. We tried to test the acceleration time on a closed circuit, but driving into a very strong headwind the big SUV could manage only 4.4 seconds - which is still a very quick time given its size and luxury.

The engine is paired to an eight-speed automatic transmission and Audi’s trademark quattro all-wheel-drive system to help smoothly transmit so much power to the road.

Seriously? This is a 2.0-tonne twin-turbo petrol V8 with a 90-litre fuel tank. Even the Porsche specs sheet doesn't understand the question because in the column for fuel efficiency there are three letters - tbc.

My own testing saw me record 22.5 L/100km at the fuel pump, which means I enjoyed driving the car very much.

A little digging around reveals Porsche globally claims the Turbo GT will use 12.6L/100km, over a combination of open and urban roads.

You might not have as much fun as I did but easing back a little might get you closer to the 700km of range this more frugal consumption figure appears to offer.

While efficient it isn't, I'm not going to mark the Turbo GT too much here because compared to its petrol rivals the fuel consumption is what I'd expect from such a high-output heavy SUV.

Unfortunately you don’t get the most powerful production engine without some trade-off, and for the RS Q8 Performance that means significant fuel consumption. The official fuel economy rating is a very thirsty 12.2L/100km, but that's the best-case scenario too. If you partake in some spirited driving that unleashes the full potential of the engine will result in a higher rate of premium unleaded being consumed by the big V8. We saw returns in the high teens across our time, but that was largely open road driving, so we’ll reserve final judgement for an extended test drive across more varied conditions.

Thankfully there’s a fairly large 85L fuel tank, so if you can hit the claimed average you can get a theoretical 696km of range.

Never have I met a car this powerful and superbly athletic that is as pleasurable to drive alone on great, fast roads as it is to pilot at 50km/h in the suburbs with a family on board.

It exceeds my understanding of engineering that something this large can move so quickly. That in an instant can turn and tip into a corner with such precision and effortlessness.

Yet it can switch seamlessly and happily to coping with speed bumps and potholes, delivering a ride so comfortable it'll send babies off to sleep. And it did.

The only issue, and this is such a tiny thing, is the dash-mounted gearshift, which means having to reach up and select Drive or Reverse or Park, which, when executing a three-point turn, is necessarily frustrating.

Still, I'm giving the Turbo GT a 10 out of 10 for driving under all conditions, and we didn't even go off-road, which of course you can do, as long as it's not too wild.

Obviously the RS Q8 Performance is all about speed, Audi made its intention clear by sending it to the Nurburgring to set a new SUV lap record for an SUV. But the reality is most owners are unlikely to hit the racetrack in the RS Q8, so what’s it like on the road?

In a word? Impressive.

While the engine is undoubtedly the star attraction offering up so much effortless performance, the RS Q8 Performance wouldn’t be so quick around the Nurburgring or as nice to drive on the road without its highly advanced chassis systems.

It has an array of technology to help it handle, it has active air suspension, adaptive dampers, active roll stabilisation and all-wheel steering, which help to make this big SUV handle like a much smaller car.

The suspension does a remarkable job of providing a compliant ride on such large alloy wheels, while also providing responsiveness.

The handling is certainly helped by the all-wheel steering, which gets the rear wheels to turn in the opposite direction to the fronts at low speed (below 50km/h), but in the same direction at high speed (above 80km/h), making the big SUV feels much more direct when changing direction.

As for the overall experience, that’s helped by Audi’s surprising decision to actually remove some of the sound insulation, which allows you to hear the engine even more than you ordinarily would. This really plays to the dynamic nature of the RS Q8 Performance.

The RS Q8 Performance comes stacked with the full suite of active safety features. These include adaptive cruise control, lane change warning, rear cross-traffic alert and surround-view cameras.

ANCAP rated the Q8 as five stars back when it first launched in 2019 and that rating is due to expire at the end of 2025. However, ANCAP states that it only applies to the 3.0-litre Q8 models, not the V8-powered RS variants.

The Cayenne Turbo GT is covered by Porsche's three-year, unlimited kilometre warranty, which is lagging behind in terms of duration even compared to other luxury brands such as Mercedes-Benz, which offers five years.

Servicing is recommended annually or every 15,000km, although there isn't a capped price maintenance plan with final costs determined at the dealer level (in line with variable labour rates by state or territory).

Despite the extra power and fancy new brakes, the RS Q8 Performance costs the same to service as the existing RS Q8.

That means $4690 for Audi’s five-year service plan, and $5720 for the Audi Advantage.

The latter package includes an extra two-year, unlimited kilometre warranty on top of Audi’s five year/unlimited km coverage. It also includes two extra services and two more years of roadside assistance, to keep you covered for seven years total.

That’s good, but it’s still an extra cost when many mainstream brands already offer seven years of coverage as standard.