While most of the focus in endurance racing has been on the new LMDh offerings, that’s certainly not to say there’s no new developments in the world of GT4 competition, with the McLaren Artura and new BMW M4 set to race across the globe in 2023.
McLaren’s previous model, the 570S, was released in 2016, with the British manufacturer selling more than 180 examples, the last being produced at the start of this year. Despite having achieved considerable success over a six-year period, culminating in last year’s GT4 European Series crown, the age of the model was beginning to show, according to McLaren Automotive’s director of motorsport Ian Morgan.
“The 570S was done as a way of getting us into GT4 racing and I think it’s been very successful in achieving that, but we’ve learned a lot from the limitations of the car,” he admits. “We kept the initial car very much based around road car systems but then were not able to tune the performance of the car up and down, which has been an issue for us going forward. As other manufacturers change and improve, we’ve ended up being locked into a position.”
Malcolm Gerrish, chief engineer of the Artura, adds: “The 570S was the right car for the right market at that time, but now GT4 racing has evolved so much we have to evolve with it.”
It’s a similar story for BMW with its older M4 model, released in 2017, despite it receiving an evo package last year. That allowed Century Motorsport pair Will Burns and Gus Burton to claim last year’s British GT title, with Burns and Jack Brown also winning at Snetterton this year.
“The old car was super-reliable, the ultimate 24-hour or endurance car,” says Century boss Nathan Freke. “It had a lot of road car stuff, the traction control was wet, dry or off, there was a gearbox mode but that was kind of it really. It is absolutely time for a new car, we maximised the old car because we ran it for five seasons.”
What’s new?
Driveability. It’s a word used repeatedly by both manufacturers and is the single biggest focus point for the design teams at McLaren and BMW when developing the new machines. Perhaps unsurprisingly when it is often gentleman drivers forking out for their latest products.
“They focused a lot on the driveability for the Am drivers, just make the car easier to drive,” says BMW Junior driver Dan Harper. “They did a very good job on that, because the main thing is you feel comfortable in the car. Especially for the Am drivers, if they feel comfortable then they normally go faster.”
Harper believes the M4 is “much more of a race car” than the older model, with stiffer suspension and the addition of aspects from the GT3 machine, including the steering wheel and dashboard, helping to enhance that feeling.
"It was one of our test points, not specifically for that race, but for the project to see how the [M4] handles a puncture. The car came into the pits, we fitted a new set of tyres and we continued the race so there was not a single issue" Richard Wesselak
The car has a V6 twin-turbocharged engine, as well as 10-way traction control and adjustable front and rear camber, but Richard Wesselak, head of the project, says “nothing exceptionally has been pointed out from the customers”.
“There were a couple of things which we thought might have been the weak points,” he says. “We’ve looked at the whole thing, be it systems or chassis set-up, we’ve tried to build on pretty much everything that we could.”
Unlike the Artura, the new M4 model has already been thrown into a racing situation with factory-run outings in the Nurburgring Endurance Series and the 24 Hours of Portimao, where valuable data was accumulated.
“When you have multiple cars on track it always creates different issues, just running behind other cars can become an issue,” adds Wesselak. “There were some issues with punctures for many cars and we also suffered one or two punctures [using Hankook tyres].
“It sounds funny, but it was one of our test points, not specifically for that race, but for the project to see how the car handles a puncture. The car came into the pits, we fitted a new set of tyres and we continued the race so there was not a single issue. That’s also a very strong point for the car.”
“In the past if you had a fast car, you could even probably compensate some reliability issues that you had,” says Dominik Nadler, BMW’s head of track operations. “But nowadays there is five, six cars finishing within a few seconds and if you have any reliability problem you will be out [of contention].”
Driveability, reliability as well as a sense of enjoyment are all aspects McLaren has tried to incorporate into the Artura too.
“It’s got to be consistent,” says Gerrish. “There’s no point in having a car that is ballistic fast when you’re on the peak of the tyre, and then it just drops off and becomes unpleasant for the Am to drive, that’s not what we want. We want something that is as consistent as possible, that’s how you work in our world. If a driver is engaged and enjoying the car, they will push themselves more.”
The new Artura is 220lb lighter than its predecessor and incorporates a carbon chassis. The front wheel width has been increased to offer more grip and less tyre degradation, while a mechanical limited slip differential offers increased rear grip. Radiators have been moved inboard, while the rear bodywork is now detachable without having to remove the rear wing, making the car more serviceable for teams.
As with BMW, a full motorsport system has been placed on the car, moving away from the road car ECU on the 570S, with adjustable traction and ABS controls – even down to different mappings depending on if the car is using Michelin or Pirelli tyres.
Perhaps the biggest difference, at least compared to the road car, is what will power the Artura GT4. The hybrid power unit has been removed for the racing version, with the 120-degree, twin-turbocharged V6 engine solely powering the car, although Gerrish says this redesign caused surprisingly few headaches. Space under the monocoque where the hybrid battery of the road car would sit, for example, now houses the fuel cell and ancillary drive system, keeping weight central and low down.
Making a product which is both consistent and engaging takes on even more importance in the world of GT racing, where Balance of Performance can either hinder or help cars due to changes in power output and weight.
“In our world it’s BoP racing,” says McLaren factory driver Rob Bell. “Performance is a target and we want to win every race we enter, however the reality is that won’t happen because certain cars will be given BoP breaks at certain circuits. It might not suit our car, so actually the goal is that the car feels good to drive and it’s engaging.”
"The car should never be in a unique scenario with the customer that it hasn’t been in our hands. Hence Daytona and Sebring are unique tracks so we need to go there first so we know what the car will do" Malcolm Gerrish
McLaren has worked hard on this aspect, incorporating Am drivers as part of its development programme, which included a 36-hour test at Paul Ricard, while there have even been outings at Sebring and Daytona.
“The car should never be in a unique scenario with the customer that it hasn’t been in our hands,” says Gerrish. “Hence Daytona and Sebring are unique tracks so we need to go there first so we know what the car will do.”
No stone has seemingly been left unturned by both manufacturers, which is even more impressive given the new cars have been designed, built and developed under the cloud of the COVID-19 pandemic, as well as a global shortage of parts. Yet both have produced their cars to schedule, with customer orders being taken for 2023.
What to expect
BMW has yet to release official figures on how many cars it plans to build, but Harper says “there’s a waiting list, so there’s plenty of customers waiting to buy it”. Century Motorsport will run two of the new M4s next year, one of which will be used in January’s Dubai 24 Hours.
“I’ve worked with BMW for five years and one thing I’ve learned with them is they are very straightforward,” says Freke. “If it’s bad, they say it’s bad. If it’s good, they say it’s good. This new GT4, they’re really punchy about what they’re saying, so my view is it’s going to be good. We’ve got a massive amount of interest in next year [from drivers], I’ve never received interest like it before and it’s down to this new car.”
McLaren already has 48 confirmed orders, with the Artura GT4’s expected race debut coming in the Daytona 24 Hours-supporting IMSA Pilot Challenge series. A number of the new cars will also be used in the new-for-2023 McLaren Trophy, a one-make championship aimed at Am drivers where the Artura will be free of BoP restrictions, that is all part of McLaren’s push to bring its customer base from the road to the race track.
“The cars look like the road cars, there’s a proper direct link between a race car and a road car,” says Morgan. “It’s the real way you can race on a Sunday and sell on a Monday, and I think that’s important to all of us as manufacturers.”
They may look like the road-going versions, but under the skin the latest racing products from McLaren and BMW promise to be much more.
Other new GT4 cars coming in 2023
It’s not just McLaren and BMW that will begin the season with new GT4 cars, as the Nissan Z (left) and Lotus Emira will also hit the track in 2023.
The Nissan Z, which was unveiled at the SEMA show in Las Vegas last month, will be provided to pilot customer teams in the SRO’s Pirelli GT4 America series and Japanese Super Taikyu Series. Nissan has completed extensive testing of the twin-turbo V6 racer, which will be capable of 450bhp subject to Balance of Performance, and comes fitted with a SADEV six-speed sequential gearbox and Ohlins two-way dampers.
Speaking at SEMA, Nissan’s global programme director Michael Carcamo said: “We’re in the throes of preparing for the 2023 season – testing here locally – and we look forward to continuing to talk with teams and continue to establish the Z as a force to be reckoned with on tracks around the world.”
That means it could soon be represented in British GT for the first time since 2018 with the GT3 GT-R and GT4 370Z.
Another marque that has already made something of a return to the championship is Lotus, which took eight GT4 wins between 2011 and 2015 with its previous model, the Evora. Its latest road-going model, the Emira, has been used as this year’s safety car, and will be available for customers to race next year.
“GT4 is a wonderful category for us and it fits really well with the Emira because it allows us to prove that car through motorsport,” says managing director Matt Windle.
"On the first day we ran it, we got 400-odd kilometres out of the car, we just ran it all day, so it’s been very reliable from day one" Simon Lane
The car (right) will feature a transversely mounted 3.5-litre supercharged V6 Toyota engine capable of 400bhp (BoP dependent), Hewland six-speed sequential gearbox and two-way adjustable Ohlin dampers. RML is set to build the cars, the first of which are expected to be produced by the end of the year. Lotus Advanced Performance executive director Simon Lane is looking forward to showing off its “epic noise”.
Insight: How Lotus is gearing up for its eagerly-awaited motorsport return
“The first day we fired it up and ran it around the track, I stayed out with the team for a few hours,” he says. “I went back to my office and was struggling to concentrate because all I could hear was the car! On the first day we ran it, we got 400-odd kilometres out of the car, we just ran it all day, so it’s been very reliable from day one.”
