Mazda MX-5 vs Audi RS4

What's the difference?

Ultimately, the design and tech changes to the ND MX-5 will be the biggest day-to-day advantages of the updated model, because the mechanical changes don’t make themselves hugely obvious on the road.

If you’re into track days, it’s still a satisfying car to hustle as fast as you can, but it’s at its most accessible on winding roads for weekend drives, where the new differential and track DSC mode won’t come into play as much.

But in a world where accessible sports cars are becoming a rarity, there’s only one rear-drive convertible with a sticker price appropriate for financial mortals, and it’s a pretty damn good thing that it’s the ND MX-5.

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

What a way to send off this generation of Audi RS4 and RS5. The extra focus courtesy of those trick coil overs and drama from the exhaust plus the sharper gear changes deliver the best Audi has done with these RS products. 

There are some compromises, with the suspension favouring outright control over low-speed comfort. It’s also true that the current BMW’s M3 and M4 are more impressive, but when the products are nearly seven years fresher than Audi’s, what do you expect? 

Plus, those looking for a more restrained and polite fast executive sedan (or wagon) will gel with the Audi’s sophistication. There aren’t many of these Competition Plus RS4 and RS5s coming to Australia and they are impressive visually and from behind the wheel. It’s a fitting way to send off the current generations.

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

Alright, we’ve all seen ND MX-5s, you don’t need me to tell you about its proportions or explain its design elements to you in too much detail, so I’ll give you the headline changes.

At the front and rear are new pairs of LED head- and tail-lights, respectively… obviously, fitting into the spaces the old ones took up.

The DRLS and reverse lights have come off the bumpers for both, and are now part of the main lights at each end - no more DRLs in the front bumper, and the reverse lights have been replaced by reflectors.

There are new 17-inch wheel designs for the base and GT trim levels, too, and there’s a new colour - Aero Grey.

Inside, it’s a shame that the tan Nappa leather interior of the RF Black Roof can’t be had in a manual roadster, because it’s gorgeous, even though the inside still looks refined enough for a simple sports car in its base cloth trim.

The RS4 Avant’s 'Progressive Red' metallic helps the black milled 20-inch alloy wheels pop. Its stance is hugely purposeful with wheels tucked right up in the blistered arches courtesy of the lowered ride height — it's how the Avant would have looked in a design sketch.

The visual bulk of the long-roofed RS4 gives it the sort of proportions motoring journalists love to wax lyrical about, even if plenty of buyers still prefer coupes or lifted SUVs. 

The RS5's more flowing, elegant lines match well with the Navarra Blue paint work, silver-accented wheels and conventional leather-appointed seats within. 

Both cars have effectively identical front cabins reflecting Audi’s classy and sleek design language. The integration of technology is pretty good and the RS4’s additional red styling pack really makes it feel sporty within.

One thing Mazda has significantly changed for the ND is the multimedia screen, now a larger 8.8-inch touchscreen running Mazda’s updated software.

It brings the MX-5 up to date without sacrificing simplicity and makes it a little easier to use. The physical dial and buttons for controlling the screen also remain. The USB-C ports are also new.

Oh, and the MX-5 is the first Mazda model to get Connected Services, which is coming to other Mazda models eventually.

Connected Services allows owners to find, lock, and get alerts for their cars from a phone app, even letting them set curfews to notify them if the car is started during certain hours.

Aside from that, another small tweak is the simplified instrument cluster, which aims to be easier to read even when the roof is open and the sun is bright.

The cabin isn’t built to be plush, it’s built for ‘Jinba Ittai’, Mazda’s philosophy that applies most strongly to the MX-5 which means ‘horse and rider as one’.

And trust me, you feel one with the horse- er, car, when there’s not ample room to move. It’s not restrictive, but it’s cosy. 

Everything’s quite well-placed and it’s not busy with buttons or features in here though, it’s made for focusing on driving. 

One downside is the lack of storage, not even a glovebox, in front of the passenger, and the central storage spot under where your elbow sits is tiny, good for keeping the key fob snug though. Also, the cupholders are able to be removed or swapped between the space behind your elbow, or above the passenger footwell.

There’s also a small storage space between the seats behind where your elbow would sit, though it’s tricky to access while you’re driving.

Then there’s the boot, which is usable for a small amount of luggage at 130 litres in the Roadster and 127L in the RF hardtop.

Finally, as a huge positive, probably the biggest advantage of the ND over any other convertible is how easy it is to open and close the roof in the Roadster. You can do it single-handed, which is great if it starts raining and you’re at a traffic light or able to quickly pull over.

The RF hard-top has a switch that automatically opens and closes the roof section.

The RS4's cabin is excellent, with a good mix of physical buttons and responsive touchscreens for control. There’s enough storage space for this kind of vehicle, with good door bins and well-sized cupholders in the centre as well as USB-C and -A charge points. 

Audi’s multimedia system is friendly though the large touch targets and dark background aren’t as crisp as those fitted to the latest rivals. The screen isn't as big, either, measuring 10.1 inches for the multimedia item. The RS4 supports wireless Apple CarPlay and Android Auto.

That said, Audi’s 12.3-inch digital driver’s display with bright and poppy mapping software and generous customisation remains right at the head of the pack. 

There is a panel of switches below the touchscreen for climate control, physical selection of the five-or-so drive modes and a collection of helpful buttons on the perfectly-shaped and sized leather-appointed steering wheel.

It lacks F1 or DTM wow-factor compared to the C63 and M3 with their easy-access driver mode buttons and toggles on the steering wheel but the RS4's restrained looks will resonate with those that prefer a bit more elegance inside. 

Neither the RS4 nor RS5's back seats are designed for those over about 175cm. The RS4’s roof is a little higher so it is good enough for most adults but the RS5’s sloping profile compromises things. It has two individual buckets compared to the RS4’s three-wide bench. 

Rear seat passengers get air vents, an individual climate zone, bottle holders in the doors, USB charge points and ISOFIX attachments for the outboard seats, with matching top tethers in the seat backs.

The Audi RS4’s boot is a generous 505L with under floor storage and a netted area on the driver’s side. Folding the 40/20/40 split-fold bench increases space to 1495L. That said, the RS5’s 465L is still very good, though it is not quite as practical in the real world. 

Being fitted with roof rails makes for sleek integration of roof racks for the RS4 to slip roof pods, bike racks or whatever else you might choose to take on a trip away.

You'd expect the RS5 to be more popular given how uncool wagons are these days but Audi's whole thing is wagons — or Avants, for the initiated — so it makes sense that the RS4 Avant outsells the RS5 Sportback about two-to-one.

For the RS4 Avant’s basic asking price of $165,015, before on-road costs, you get luxury features such as LED headlights, an RS design package, Nappa leather upholstery, power-adjust seats, a Bang & Olufsen 19-speaker sound system and metallic paint on top of the significant changes to the RS4’s chassis and zingy 331kW V6. 

The RS5 is a little dearer, reflecting the addition of Matrix LED headlights that aren’t available on the wagon.

But we have the 'Competition Plus Pack', which is a $13,990 indulgence that swaps adaptive dampers for Audi’s 'RS Sport Suspension' coil over package with manual rebound and compression adjustment and height adjustment.

The cars sit 10mm lower than a normal RS4 but you can go to a dealer to move the ride height up or down from there. 

That’s not it, though. You also get a louder exhaust system with matte black pipes, fixed-ratio steering system, a retuned eight-speed automatic with more aggressive shifts, different rear differential programming, black exterior badging, 2.0kg lighter 20-inch Audi Sport wheels (in silver or black), special LED entrance lights and your speed limiter raised to 290km/h.

The 'Navarra Blue' RS5 pictured is a ‘basic’ Competition Plus. You can go further, as done with the RS4 Avant with its manual-adjust bucket seats ($1300), 'Interior Design Pack' in red ($3400), matte carbon exterior pack ($6300) and carbon trim, bringing its total cost to $191,405, before on-road costs. 

That makes the RS4 and RS5 the most affordable in their competitor set, below a BMW M3 Competition xDrive Touring ($183,500) and Mercedes-AMG C63 S E Performance hybrid, which is $187,900, before on-road costs.

Up front, you get one option: a 2.0-litre naturally aspirated four-pot. It makes 135kW and 205Nm, and it’s a delightful little thing, driving the rear wheels only - as it should.

It used to be that the smaller 1.5-litre engine was the more revvy, keen option, rest its soul, but Mazda updated the 2.0-litre to be more eager (and deliver more power) at high revs and basically made the little 1.5-litre redundant.

Anyway, you can have it with a six-speed manual in any variant, or a six-speed automatic in GT guise if you find manual gearboxes difficult or a hassle.

Audi’s 2.9-litre twin-turbo petrol V6 has seen plenty of use across performance products from Audi and Porsche, including the Macan S and Audi S6. 

In the RS4 and RS5 Competition Plus, it develops the same 331kW (at 5700-6700rpm) and 600Nm (at 1900-5000rpm) as the regular car. This makes it an extremely flexible engine that delivers predictable punch anywhere in the power band.

That said, it lacks the explosive character of BMW’s twin-turbo inline six — the figures are only 15kW and 50Nm higher on paper yet the M3’s response is that much more ferocious. 

Audi’s RS division has tried to capture a bit more emotion, retuning the eight-speed torque converter automatic transmission for crisper shifts. This also benefits the RS4’s 0-100km/h sprint time, which falls two tenths to 3.9 seconds in Competition Plus guise. 

The V6 breathes a little easier, too, with a different exhaust. Audi says the extra sound is down to 8.0kg less sound deadening in the car.

There’s more resonance at idle that does feel tiring sitting in traffic idling but the trade-off is a brawny mid-range baritone that develops into a shrill bark approaching the redline.

Mazda says the MX-5 uses 6.8L/100km as a manual Roadster, or 7.0L/100km with an automatic gearbox. Or, in the heavier RF 6.9L for a manual and 7.2L for auto.

Not great for a tiny car like this, but pretty good for a sports car!

It’s got a 45-litre fuel tank, takes premium 95 RON or higher, and while it should hypothetically be able to travel more than 600km with its on-paper claims, expect fuel use to sit closer to 8.0L/100km if you’re driving it anything like it deserves.

The Audi RS4 wagon is rated to use 9.5L/100km in ADR combined cycle (urban/extra-urban) consumption testing while the slipperier RS5 returns 9.4L/100km in the same test. 

We weren’t able to run accurate or particularly relevant fuel figures on the event but the trip computers showed around 12L/100km in both RS4 and RS5. 

While these numbers are high compared to your average passenger car, the Audi is more efficient than BMW's rivals, and gets remarkably close to the hybrid C63 in the real world.

The fuel tank is quite small for this kind of vehicle at 58 litres. That limits the RS4’s theoretical driving range to 611km. 

Unsurprisingly, the Audi RS4 and RS5 require 98 RON premium unleaded petrol. 

It feels like every motoring journo under the sun (literally if the roof is off) owns or has owned an MX-5 of some sort.

And the first time you drive one, you might understand why. 

If you spend your days testing and driving a bunch of different cars that aim to be many things at once, it’s refreshing to drive something that aims to be one: fun.

That’s it, the MX-5 feels like it was built to be fun. Not for convenience, not for power, certainly not for the school run.

And fortunately its simplicity remains with this update. All Mazda has done to change the way it drives is attempt to improve the rear limited-slip differential and improve the steering a little by reducing friction in the rack, as well as improve throttle response.

Has any of that changed the way it feels to drive on-road? No, not massively, but the ND was already such a delight that Mazda could have kept this update to purely design and interior tech changes and it would have still been one of the best-value buys around in terms of fun.

The MX-5 still feels relatively softly sprung while still being a dynamic and communicative sports car that’s engaging to drive even at low speeds, and rewarding (or frustrating) to drive fast.

On tight, winding roads, the MX-5 is at home, its soft suspension keeps you humble with its shifting weight and its relatively meagre outputs keep your licence safe.

In fact, despite being slightly compromised as a daily drive, the MX-5 is still plenty of fun even in traffic, there’s something about the satisfying click as the shifter slips into gear, or the little rev matches heading back down through the cogs when approaching a red light.

The 2.0-litre four-pot is a keen unit, and the six-speed manual is light and easy to work with, plus its steering is light without sacrificing road surface feedback - that feedback can quickly turn into cabin noise on a coarse highway which could become a little irritating on a long trip.

But the MX-5 can still be plenty of fun on track, where you’re more likely to get the most out of its new limited-slip differential and Track DSC mode.

It’s equally frustrating and satisfying to hustle the MX-5 around the East Circuit at The Bend in South Australia, where the track is twisty, busy, and unforgiving. Get it wrong, and the MX-5 lurches or slides to let you know you’ve made an error. 

Get it right, however, and the little roadster glides through the corners, camber changes and even over apex kerbs smoothly and carrying impressive speed.

Plus, the electronic assistance won’t usually kick-in until you really need it, a welcome change from cars that are constantly trying to keep you from having fun behind the wheel.

The time allocated to driving the RS4 Avant Competition Plus was fairly limited and we were sadly unable to sample how the highly adjustable coil over suspension performed where it makes most sense — on the racetrack. 

Still, winding country roads between Sydney and the Southern Highlands served up some challenges, demonstrating how the Competition Plus pack changes the character of the RS4 and RS5. 

The only real negative is comfort, specifically over those horrible plastic speed bumps that litter shopping centre car parks. With adaptive dampers, carmakers can set programs for these kinds of obstacles to soften and stiffen the clever shocks at just the right time. Not so the Competition Plus pack cars, which ride these bumps harshly.

That about does it, though, and everything thing else is a net benefit. The steering system addresses some criticism of the earlier RS4s. Further than a retune, the Competition Plus gets a new rack, that is non-progressive with a fixed ratio of 15:1 (instead of 13.3:1) and 2.4 turns lock-to-lock. The reactions to each input feel a hint more faithful. 

When above 40km/h the coil overs come into their own. Even though the RS4 rides firmly it doesn’t constantly jiggle over small bumps. Over sharp-edged hits, the suspension rounds the hits off so, while you feel them, there’s a sense of control and sophistication. 

Having speed limits to contend with means it is essentially impossible to find the limits of grip of the 275/30R20 Continental SportContact 6 tyres on the road and there isn’t much body roll, either.

The RS4 is still rewarding, though, getting up on its toes just enough through a series of bends to feel engaging. It gives an impression of being quite light and at 1820kg it is now considered featherweight next to rivals.

The RS4's Quattro all-wheel drive system favours the rear wheels when driving normally (60 per cent rear) and can send up to 85 per cent of the drive to the back axle. 

The tweaked electronically-controlled rear limited-slip differential amplifies the throttle steer-ability of the RS4, giving you the confidence to squeeze the gas on exit. 

It helps that the Competition Plus bucket seats are a little thinner and set closer to the floor giving you more feedback. This is the key differentiator between the RS4 and RS5 we drove — the buckets make the car feel alive. 

Strong brakes are made up of 375mm front rotors clamped by six-piston calipers. Optional carbon ceramic brakes with larger 400mm front rotors help save 6.5kg and, if you plan to use the RS4 on track, are a smart buy along with a set of Pirelli P Zero Corsa semi slick tyres ($850). 

Really, though, neither the RS4 nor RS5 are the perfect car for the track. They are plenty capable and fast on the road with just enough fun, reward and character thrown in to keep you coming back for more.

The Audi A4 range was rated a maximum five stars in ANCAP safety testing in 2021, with the rating now considered expired. The stamp also only applied to four-cylinder models — so not the RS4 we drove. 

It has lots of safety equipment, including eight airbags (dual frontal, side chest, front and rear side head curtains), autonomous emergency braking (AEB) functional up to 250km/h with pedestrian detection, front and rear cross-traffic alert, lane-keep assist, blind-spot monitoring, safe exist warning and tyre pressure monitoring.

Adaptive cruise control with lane-trace assist makes it an easy car to use on the motorway. The systems are well integrated and easy to switch on and off as you like. 

Mazda’s five-year, unlimited km warranty covers the MX-5, including five years of roadside assist.

Servicing costs are pre-set, with intervals every 12 months or 15,000km up to seven years or 105,000km. They cost between $447 and $638, averaging out at about $544 each.

Audi covers the RS4 and RS5 with a five-year/unlimited kilometre warranty which is now the expected norm across the premium part of the market. 

A five-year service plan can be pre-purchased, costing $3630 for both models with maintenance due annually or every 15,000km. 

After the five-year warranty period, owners can choose to extend the service packaging and warranty for two extra years at a cost of $4260. This can be done twice, extending the warranty up to nine years.