Nissan has done well keeping its upgraded Z under wraps. We've only glimpsed a couple of test vehicles, but thanks to an enthusiast at NissanZClub, we have another look at what could be a new Nismo model.

Specifically, we have Sean in Arizona to thank for this glimpse. He caught two prototypes on camera, getting a pretty good look from both the side and rear. Fortunately, the side views also capture a bit of the front, as we believe that's where a significant change from the standard Z will occur. We're talking about the split grille, which Nissan debuted on the Fairlady Z Customized Proto just over a year ago. More importantly, the automaker announced in early January that the split grille will enter production as a dealer-installed option for Japan-spec cars, later this year.

Gallery: Nissan Z Nismo Spy Photos

Our previous Z spy photo session showed prototypes with and without heavy camouflage, but in both cases, we could make out some kind of strip or panel across the top of the grille. We see the same feature in these new images, and while it could be a false panel, Nissan's recent announcement of the split grille in Japan makes it even more likely it will be a distinctive Nismo feature for the US.

Speaking of Nismo, there's more happening than just a new retro-inspired nose. A modest body kit should come with the upgraded Z, and we can see what looks like big side sills mounted between the wheels in these new images. Look behind the wheels and you'll see noticeably larger brake rotors in front. Though not visible here, we've seen other test vehicles with NACA-style vents in bonnet camouflage.

At this point, we've heard nothing in the rumour mill about changes to the engine. It's safe to assume some extra power will be coaxed from the 400-bhp twin-turbocharged 3.0-litre V6 engine. In the standard Z, that power goes to the rear wheels through either a six-speed manual or nine-speed automatic transmission.

Similarly, it's hard to say when this car will be revealed. There's been very little chatter from our normal spy sources, but with the Japanese-spec Z getting the split grille option later this year, seeing something revealed for the US market in the second half of 2023 is a real possibility.

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