Lexus RZ 450e prototype 2022 review

2022 Lexus RZ450e MtE 030
Brand’s first bespoke electric car introduces an exclusively by-wire steering system

Welcome to the RZ 450e, which is the first Lexus to be built on a dedicated EV platform. However, it’s not the first all-electric car from the Japanese premium brand. The Lexus UX 300e has that accolade, but the RZ 450e is arguably the more important.After sitting on the fence for so many years when it comes to electrification, preferring to stick with its self-charging hybrid philosophy, for LExus the RX is a firm signal of zero emissions intent. So, what can we tell you about this eye-catchingly angular model? Well, we could highlight the fact that it sits on the same e-TGNA architecture already seen on both the Toyota bZ4x and the Subaru Solterra.Or that its twin motor set-up packs 309bhp and that there’s a 71.4kWh lithium ion battery beneath the floor that should give a range of more than 250 miles. But what you really want to know is what this Lexus doesn’t have, which is a direct connection between your fingertips and terra firma.Yes that’s right, when fitted with the One Motion Grip set-up, the RZ delivers fully fly-by-wire steering. Now, Lexus isn’t the first to dabble in digital direction changing, because Infiniti attempted it with its G50 saloon a few years ago.But in that system there was still a mechanical connection, a failsafe in case the computer said ‘no’. Not so in the Lexus, which relies on the built-in redundancy approach of most commercial airliners, with duplicate back-up systems that can step in to save the day.Essentially you get a standard steering rack (you can get an RZ with conventional steering if you want) that’s powered by an electric motor which is sent instructions from sensors at the steering wheel.And with no direct forces acting on the helm, another motor is required to deliver feedback to the driver, the set-up increasing opposing torque to simulate a ramping-up in loads as cornering forces build. It looks fairly straightforward on paper, but a near 12-year development programme proves that it’s anything but.What’s this unusual steering setup like? Good question. Another question would be, does it actually work? The short answer to both is ‘interesting’ and ‘yes, up to a point’.First things first, however, because before the RZ even turns a wheel you’ll notice that there’s no wheel to turn. Instead you’re confronted with an aircraft style yoke, a design chosen because steer-by-wire can virtually alter the rack ratio from very high to very low and almost anything in between (Lexus weren’t keen to divulge numbers).As a result, there’s only 150 degrees of steering movement from lock-to-lock, meaning there’s never any need to take your hands off the quarter-to-three position.To sample this set-up we’re given a handful of laps at the undulating Parcmotor Castelloli track just outside Barcelona, each punctuated by a visit to a tight, slalom-style course. Out on the circuit the system feels remarkably natural, and if anything the weighting in this pre-production car was meatier and more confidence-inspiring than a conventional pre-production RZ we sampled back-to-back over the same course.Only in the sharp hairpins do you start to really notice its effects, the car feeling much keener to turn-in, almost over-rotating toward the apex for a surprising sense of agility.Segue to the slalom, however, and it takes at least one run for your brain to recalibrate and calm your inputs to avoid cutting corners way too early, as even the sharpest switchbacks require less than half a turn of lock. Yet you quickly adapt and are soon marveling at the car’s minimum effort manouverability.There are quirks, though. Apply lock too quickly at low speed, and sudden steering effect can cause quite a bit of a head toss. Moreover, when you do ask for a lot of steering angle in a hurry when manouvering, there’s just the slightest sense of lag, a feeling the computer needs a fraction of a second to process the command. Also, a quick squirt on a low grip surface revealed that the steering becomes incredibly stiff and heavy when applying rapid opposite lock to counter a slide. It’s a trait that used to blight the Infiniti and is one that the Lexus engineers are aware of, but it’ll need work before One Motion Grip gets anywhere near any future Lexus or Toyota sports car. Anything else? Well, these are very much prototypes in terms of their finish, while our time in the cars was restricted to a billard smooth race circuit, so definitive dynamic verdicts will have to wait.Perhaps most surprising was how light and vague the conventional steering felt around the track after a turn in the One Motion Grip car, even if it felt more natural spinning the wheel this way and that through the slalom.That said, in both steering guises the RZ feels planted and poised, the rear electric rear motor even helping to tighten your line on exit under throttle thanks to the ability to deliver 80 percent of the overall torque when cornering.And while the Lexus will ultimately understeer (the front tyres are 235 section, while the rears are 255), it corners with decent composure and relatively flat. It feels refined too, the whine of the motors well suppressed, plus road and wind noise are muted. And what bumps there were, it rode with decent compliance, only a particularly sharp transverse ridge sending a sharp report shuddering through the structure and a sideways shimmy through the suspension.It’s also roomy inside. In terms of its external dimensions the RZ falls between the mid-size NX and RX in the brand’s SUV pecking order, but with a longer wheelbase than the latter it serves up more room to stretch out.Other neat features include a dimmable panoramic glass roof and radiant heaters in the footwells ahead of the driver and passenger that use far less electricity, helping improve overall efficiency. There’s also a vast 14-inch touchscreen infotainment system that’s bursting at the pixels with connectivity and features.It’s not on sale quite yet and there’s still a little fine-tuning to be done, but the RZ feels quick, composed, comfortable and refined. It’s an effective rather than exciting machine, but our brief test under strictly controlled conditions suggests there’s a likeable SUV lurking under the camouflage.Then there’s the One Motion Grip steering that’s remarkably slick and intuitive to use, even if there are some quirks that need ironing out – although in fairness it’s only in extreme situations that they manifest themselves and they never undermine the safety of the driving experience.Other than that, the only real criticism is that the expected range of just over 250 miles is not much to write home about, especially when you can go much further for less elsewhere.Yet Lexus luminaries seem unruffled, suggesting that its research suggests it’s enough for most customer needs. Either way, we’ll have to wait until we sample production ready machines on the road to deliver our definitive verdict, but the initial signs are promising.
Source: Autocar

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