Lexus IS300 vs Porsche Cayenne

What's the difference?

The new-look Lexus IS takes several steps forward over its predecessor - it’s safer, smarter, sharper to look at and still pretty well priced and equipped.

It is feeling its age inside, and the competition has moved on in terms of engines and EV tech. But even so, if I was buying a 2021 Lexus IS, it would have to be the IS350 F Sport, which is just the most fitting version of this car, though the IS300h Luxury does have plenty to like for the money, too.

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.

You either get the Lexus look or you don’t, and I think this latest version is possibly more agreeable than the IS in years gone by.

That’s partly because the brand has finally done away with the odd spider-eyes twin-section headlights and daytime running lights - now there are more traditional headlight clusters, which look a lot more resolved than before.

The front end still features a bold ‘spindle’ grille, which gets different treatment depending on the grade, and the front, to my eye, looks better than before but still very much stuck in its ways. 

At the side you’ll notice the giveaway windowline hasn’t changed, despite the chrome trim line having broadened as part of this facelift, but you can tell the haunches have muscled up a bit, with the new IS now 30mm wider overall, and the wheel sizes are 18s or 19s, depending on the grade.

The rear accentuates that width, with an L-shaped lighting signature now spanning the entire re-sculpted boot lid, giving the IS a pretty tidy rear end design.

Overall dimensions for the IS are 4710mm long, making it 30mm longer nose to tail (on an unchanged 2800mm wheelbase), while it now spreads across 1840mm (+30mm) and is 1435mm tall (+5mm).

The exterior changes really are impressive - I think it is a more purposeful but also more pleasant looking car now than it ever has been in this current generation. 

The interior? Well, there’s not a whole lot to talk about in terms of design changes, aside from the repositioned and larger media screen - which sits 150mm closer to the driver because it’s now a touchscreen with the latest smartphone mirroring tech. Otherwise it’s a carryover affair, as you can see from the interior pictures.

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.

The interior design of the IS, as mentioned, hasn’t changed dramatically, and it is starting to feel old compared to some of its contemporaries.

It’s still a nice place to be, with comfortable front seats with electric adjustment and heating across all grades, and cooling on many variants, too. 

The new 10.3-inch touchscreen media system is a nice unit, and means you can essentially do away with the silly trackpad system that still resides near the gear selector, so you may still end up bumping it accidentally. And the fact the IS now has Apple CarPlay and Android Auto (though neither are wirelessly connectable) does further its appeal on the multimedia front, as does the standard 10-speaker Pioneer stereo - though the 17-speaker Mark Levinson unit is an absolute blinder!

The centre stack below the media screen retains a CD player, and still has the electromagnetic temperature adjustment sliders as well. That part of the design is dating it just as much as the transmission tunnel console area, which looks a bit out of touch by modern standards, though still incorporates a pair of cup holders and a reasonably large centre console bin with soft armrest padding.

The front doors feature trenches with bottle holders as well, while in the rear doors there is still no drink storage - a carryover annoyance from the pre-facelift model. However, the middle seat in the back doubles as an armrest with pop-out cupholders, and there are rear air vents too.

Speaking of that middle seat, you wouldn’t want to sit in it for long, as it has a raised base and uncomfortable backrest, plus there’s a huge transmission tunnel intrusion eating into leg and foot space.

Outboard passengers also miss out on toe room, which - for my size 12s - is an issue. And it’s hardly the roomiest second row in this class for knee room and headroom, as my 182cm frame was a touch squished behind my own driving position.

Children will be better catered for in the back, and there are two ISOFIX anchorages and three top-tether attachment points for baby seats.

The boot capacity varies on the model you buy. Choose an IS300 or IS350 and you score 480 litres (VDA) of cargo capacity, while the IS300h has a battery pack that robs it of some boot space, with 450L available. 

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.

The Turbo GT is the king of Cayennes, so it shouldn't surprise anybody that it's also the most expensive with its list price of $364,700.

Lamborghini's Urus lists for $409,744  and is the Cayenne Turbo GT's not-so-subtle Italian cousin, sharing the same platform and engine.

Both are in my mind the best performance SUVs on the planet. It just depends how conspicuous you want to be.

Then there's Bentley's V8 Bentayga which isn't blessed with the Porsche's good looks but would still be all over the Cayenne if the two happened to meet at a race track.

So, why is the GT Turbo the king of the Cayennes? What makes it better? For all the reasons you'd think - it's the fastest, most powerful, most luxurious and most equipped Cayenne in the range.

We'll get into mind-bending engine and performance specs soon, but first let me take you through the standard features on a car that's anything but standard.

Coming standard and exclusively to the Turbo GT are 22-inch 'GT Design' wheels in satin 'Neodyne' with full-colour Porsche centre caps, an active rear spoiler, Turbo GT front apron, dual titanium exhaust, rear apron with diffuser, 'SportDesign' side skirts, wheel arch extensions, a lightweight carbon roof and tinted LED HD-matrix headlights.

Inside, and also exclusive to this grade, is the 'GT Interior Package' with 'Race-Tex' upholstery throughout with 'Deep Sea Blue' stitching on the front seats and centre console and the armrests and dashboard.

There's also the 'Carbon Interior Package' which includes dashboard and door trim elements.

Race-Tex trim is applied to the 'GT Sports' steering wheel, roof lining and gearshift, too.

The adaptive active air suspension, which can lower the car by 15mm, is standard and only available on the Turbo GT, too.

The soft-close doors are standard (a cost option on lower grades), as are the stainless steel pedal covers.

The rest of the features are also found on lower grades and include the 12.65-inch digital instrument cluster, head-up display, proximity unlocking, 12.3-inch multimedia touchscreen with sat nav, wireless Apple CarPlay and Android Auto, digital radio, a 10-speaker Bose sound system, heated front seats, rear privacy glass and an auto tailgate.

Four-zone climate control is standard on the GT Turbo, too, and so are heated rear seats.

Our car had several options fitted such as the front passenger display ($2860) and the Deep Sea Blue Accent Package.

The passenger display is a crowd pleaser, but as a family car my kids felt like they were missing screens in the back seats, too. Well, in my day...

The engine specs depend on the powertrain you choose. And at a glance there’s no variance between the earlier version of the IS and the 2021 facelift.

That means the IS300 model still runs a 2.0-litre turbocharged petrol motor producing 180kW of power (at 5800rpm) and 350Nm of torque (at 1650-4400rpm). It has an eight-speed automatic transmission, and like all IS models, it is rear-wheel drive (RWD/2WD) - there is no all-wheel drive (AWD/4WD) model here.

Next up the spectrum is the IS300h model, which has a 2.5-litre four-cylinder Atkinson cycle petrol motor teamed to an electric motor and nickel metal hydride battery pack. The petrol engine is good for a 133kW (at 6000rpm) and 221Nm (at 4200-5400rpm), and the electric motor produces 105kW/300Nm - but the combined total maximum power output is 164kW, and Lexus doesn’t provide a maximum torque figure. The 300h model runs a CVT automatic transmission.

The big horsepower offering here is the IS350, which runs a 3.5-litre petrol V6 engine, producing 232kW of power (at 6600rpm) and 380Nm of torque (at 4800-4900rpm). It runs an eight-speed auto.

All models have paddle-shifters, while the two non-hybrid models have seen tweaks to the transmission software that is said to “estimate driver intentions” for better enjoyment. 

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.

There’s still no diesel model, no plug-in hybrid and no full electric (EV) model - which means that while Lexus was at the forefront of electrification with its so-called “self-charging” hybrids, it is falling behind the times. You can get plug-in versions of the BMW 3 Series and Mercedes C-Class, and the Tesla Model 3 plays in this space in full-electric guise.

As for the fuel-sipping hero of this trio of powertrains, the IS300h is said to use 5.1 litres per 100 kilometres on the combined cycle fuel test. In reality, our test car’s dashboard showed 6.1L/100km across a mix of driving.

The IS300 with its turbocharged 2.0L engine is next best for fuel use, claiming 8.2L/100km. On our short launch drive of that model, we saw 9.6L/100km on the dashboard.

And the full-fat IS350 V6 petrol claims consumption of 9.5L/100km, while on test we saw 13.4L/100km.

The emissions for the three models are 191g/km (IS300), 217g/km (IS350) and 116g/km (IS300h). All three are Euro 6B compliant. 

Fuel tank capacity is 66 litres for all models, meaning your mileage range for the hybrid model could be considerably longer.

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.

With the engine at the front and drive to the back, it has the ingredients for a pure driver’s car, and Lexus made a bit of a big deal about the new-look IS being more focused thanks to chassis adjustments and track width improvements - and it does feel a pretty nimble and tied-down car in the twisty stuff. 

It is competent at stitching together a series of corners, and the F Sport models are particularly adept. The adaptive suspension in those models includes both anti-dive and anti-squat tech, which is designed to make the car feel solid and flat on the road - and it does, thankfully without feeling twitchy or uncomfortable, with good suspension compliance even in the most aggressive Sport S+ drive mode.

The 19-inch wheels on F Sport models are fitted with Dunlop SP Sport Maxx rubber (235/40 front, 265/35 rear) and there’s plenty of tarmac tenacity.

The grip from Luxury-spec models on 18s could be better, with those Bridgestone Turanza tyres (235/45 all around) proving not quite the most enthralling. 

Indeed, the IS300h Luxury I drove felt very different in character to the F Sport IS300 and 350 models. It was surprising how much more of a plush-focused model the Luxury grade feels, and likewise it wasn’t as impressive in dynamic driving due to the tyre grip and less-enthusiastic drive mode system. The non-adaptive suspension is a touch more jittery too, and while it’s not to the point of discomfort, you might expect better for a car on 18s.  

Across all models the steering is accurate and direct enough, with predictable response and decent feel to the driver’s hands for this electric power steering setup. The F Sport models have even further retuned steering for “an even sportier drive experience”, though I found at times it could feel a little numb for rapid changes of direction. 

As for engines, the IS350 is still the pick. It has the best zest, and feels the most fitting powertrain for this model. It sounds good, too. The auto transmission is pretty clever, there's easily enough pulling power, and it's probably going to be the last of the non-turbo V6s in Lexus's line-up when this cars life-cycle is up.

The IS300's turbo engine was the most disappointing, lacking some urge and constantly feeling bogged down by turbo lag, transmission confusion, or both. It felt underdone in enthusiastic driving, though in dull day-to-day commuting circumstances it came across as more acceptable, though the remapped transmission software was far less impressive in this application than in the IS350.

The IS300h was a lovely, quiet and refined experience all around. It’s the one you should go for if you don’t really care about all that go-fast stuff. The powertrain is proven, it accelerates with nice linear delivery, and at times it’s so hushed I found myself looking down at the instrument cluster to see if the car was in EV mode or if it was using the petrol engine. 

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.

The Porsche Cayenne Turbo GT hasn't been locally crash tested and so doesn't have an ANCAP rating.

That's quite normal for super high-end cars. But, when this third-generation model first arrived in 2017 it was tested by ANCAP's European equivalent, Euro NCAP, and was awarded the maximum five stars.

There's AEB which operates at city, urban and highway speeds, and lane keeping assistance, and lane change assistance which is a form of blind-spot warning, and adaptive cruise control. You can option rear cross-traffic alert, as well.

A space saver spare wheel is under the boot floor.

On paper, Lexus’s ownership offer isn’t quite as enticing as some other luxury car brands - but it has a strong reputation for blissful ownership.

The Lexus Australia warranty period is four years/100,000km, which is better for duration than Audi and BMW (both three years/unlimited km) but not as accommodating as Mercedes-Benz or Genesis, each of which offer five-year/unlimited km warranty.

The company has a three-year capped price servicing plan, with maintenance every 12 months or 15,000km. The first three visits cost $495 each. That’s okay - but Lexus doesn’t offer free servicing like Genesis, and nor does it offer prepaid service plans - for three to five years for a C-Class, and five years for Audi A4/A5, for instance.

There is complimentary roadside assistance for the first three years, too.

That said, the company has its Encore ownership benefits program that allows a number of experiences and deals, and the service team will collect your car and return it, leaving you with a loan car if you need it.

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).