2023 Smit Oletha - BMW Z4 E86 V8 GT that thinks it's a Z8 E52

Smit Vehicle Engineering’s Z4 is the Z8 Coupé that never was… Smit Vehicle Engineering's unique Oletha project fuses what a Z8 coupé could have been with 507 Roadster cues – we drive this captivating creation.

Words: Kyle Fortune

Photography: TED7

OLETHA Z4 What Might Have Been

It’s the car we wish BMW had made,” admits Willem Smit, who’s one half of Smit Vehicle Engineering. The other, his brother, Kaess, concurs, and the result of some discussions a few years previously is parked nearby as we grab a coffee. We’re on the canyon roads around Palm Springs, the brothers having driven up from San Diego, in their currently one-off, ‘prototype’ Oletha coupé. I can see it from where I’m sitting, it’s captivating but understated at the same time, a shape that’s familiar but unique, it, say the brothers, is a homage to what a Z8 coupé could have been, and by extension, having 507 Roadster cues to its lines. There’s no doubt the Smit brothers aren’t alone in dreaming up derivatives of existing products, likely you’ve all done so at some point, I know I have. The difference between them and myself, and, extrapolating here, you, is the capacity to actually do something about it. Willem’s an automotive engineer, having worked with EV pioneers Tesla, and restomod royalty, in Porsche circles at least, Singer, while Kaess weighs in with some serious engineering nous based around a career in advanced aeronautical composites for a company that had Boeing and Lockheed among its clients. That’s strong engineering pedigree, then, which explains why when Willem had a small off and some panel damage at a track day in his E86 Z4 M Coupé an idea started to form.

“I wrecked up in Sonoma and had to replace the entire side of the car. Doing so meant I knew the quarter panels bolted on and off, which was key, because with many modern cars they’re integral to the body side,” explains Willem. “Dimensionally, being a modern platform and robotically assembled means these cars are very consistent,” he adds, saying that the Oletha’s bodywork is attached to the original body mounting points. Obviously before they got to that stage, the brothers had sat down and worked things out properly, saying: “we started with a wire frame drawing, and asked if what we were considering doing was even remotely possible from a dimensions perspective.”

They admit to loving BMWs, and a family history littered with their own, and parents’ BMW and M cars underlines that, but they wanted to create something with elements of different models. A Z8 coupé, perhaps, the Z8 being a favourite of theirs, visually at least, but they wanted to make it a coupé, and more of a driver’s car than a gutsy cruiser. Using a Z8 as a basis was never going to happen, then, that due to availability, cost, as well as the chassis stiffness. The Z4’s more modern structure, allied to the coupé roof, means the Oletha’s around three times stiffer torsionally than BMW’s open Z8, which, usefully, suited the pair’s dynamic aims of the car more convincingly.

Willem’s eureka moment was a serendipitous result of not just that off, but the realisation that the Z4’s wheelbase was within 3mm of the Z8. Other elements, like the rake of the screen worked, and the drawings evolved into what I’m gawping at in the parking area. And it’s knee-weakeningly gorgeous.

“We had what I think most people would say looks like the car within a couple months and we spent probably the rest of the year refining that,” says Willem. They do concede that to finesse it they did seek out the skills of a digital modeller, who, due to other work must remain anonymous, but they describe that clandestine modeler beautifully as: “like our hands, the sculptor’s hands,” admitting that they weren’t able to do the kinds of surfacing in CAD (Computer Aided Design) that he could, saying that while they had something that worked proportionally and aesthetically it needed that expert input to get it finished properly. The result is genuinely stunning. The Oletha’s proportions are spot on, there’s a muscular tautness to its shape, it is elegant rather than aggressive, with some particularly neat detailing around things like the lights, door handles side vent with the integrated Smit roundel badge. Given the brothers describe it as a “prototype” the execution of the build is incredible, the panel fit super tight, the depth of their engineering prowess, and artistry in its execution evident everywhere. Look at something as mundane as the mechanism and fit of the rear spoiler, which, while sourced from another manufacturer, went through a load-test cycle by Willem’s girlfriend doing 10,000 step ups on a rig mounting of it to make sure it’d work as intended in its application here.

That committed, obsessive engineering-led approach is ever more obvious the more we discuss the car. The panels, all carbon fibre, are sourced in the UK, from a supplier based in Sussex, the Smits having tried numerous potential suppliers in the USA but not finding any able the Smit brother’s solution was to have the column pass through the manifolds, the duo even going to the trouble to engineer it in such a manner that should a buyer want a RHD car, that can be produced, too. Just about everywhere you look under the bonnet, there’s innovative, methodical and tested engineering, with the Oletha featuring over 100 3D printed components, including things like unique engine mounts. Smit is the first company on this scale I’ve visited who’ve shown me CFD (Computational Fluid Dynamics) schematics and have openly discussed things like NVH (Noise Vibration Harshness).

That underlines their admirable, obsessive OEM engineering approach to building their car, Willem saying that the while the engine mounts are unique, the bushings are original BMW specification to ensure that the Oletha doesn’t produce any harsh sounds or resonance under the bonnet. The ZF six-speed manual transmission, also pinched from the E92 M3, drives the rear wheels via a mechanical limited slip differential, the suspension being a KW adjustable set up, with the brakes being AP racing items, with six piston callipers up front, and four piston ones at the rear. Those callipers sit behind bespoke, forged and machined monoblock aluminium wheels of 18x9 ET30 front and 19x10 ET20 rear with Michelin Pilot Sport 4S tyres of 255/40/R18 front and 275/35/R19 rear. After the exterior, and under the bonnet the Oletha reveals its Z4 origins and a degree of ‘it works’ pragmatism from the Smit brothers. The cockpit is all but identical to the production car.

There is the option of carbon fibre touring or sports seat choices, while there’ll be some re-trimming in finer materials, but otherwise the changes are minimal. That’s not necessarily a complaint, because, in front are BMW’s simpleanalogue white on black instruments nestled deep in some cowled covers. There are no screens, no distractions, which, these days, is very much a good thing. As is the sound when it starts. The V8’s note is bassy and loud, not obnoxiously so, but there’s a hint of American muscle over the usual Bavarian culture, and it’s not out of place. Despite Smit’s goal of the Oletha being something to rival something like a 996 GT3, it feels different than that, more like a muscular, but agile, classic GT than a precision, track-biased car. Really, it’s all the better for it, with fewer compromises asaresult. Numbers, if you care, suggest a 0-60mph time of around four-seconds, and the top speed should comfortably exceed 180mph. And price? About US $450,000, depending on how you spec it. And do you know what? It feels worth it, too. Before you start doing the maths suggesting you could have a Z8 and more for that, the sort of buyers who’ll be adding an Oletha to their garage are the kind who’ll already own those, and much more besides. The Oletha transcends rational observation and comparison, too, its uniqueness, and the ability to have them build you exactly the car you want being key to its appeal. Chat over and coffees downed, and on the road what’s apparent is there’s more to it than merely its beauty.

There’saphysicality about driving it that’s wonderfully immersive, the Oletha’s throttle response being super crisp, the gearshift perfectly weighted and precise – thanks to some Smit developments in the linkage to improve the stiffness and accuracy – its short throw being quick, it eased by a clutch that’s light but feelsome under foot. There’s clarity in the steering, too, the nose quick to react, again, it delivering faithful turn in via a set up that’s loaded with the sort of detailed feel and confidence-inspiring weighting that’s uncommon these days. The chassis delivers a similarly appealing balance of accuracy blended with sophisticated control, the wheel and body control very well managed. That allows the Oletha to ride convincingly, yet not do so without feeling out of its depth or losing its composure when you raise the bar and start really pressing on. You really enjoy it without doing so, but the neat trick with the Oletha is the duality it delivers. This is a car that’s able to cover ground quickly and hugely entertainingly with an effortlessness that underlines its integrity. Ask more from it and it just keeps getting better, exploring the upper reaches of the engine’s rev range, above the 5,000-6,000rpm where it feels natural to upshift normally, and where it’s already hauling along at a decent lick, and things get even more interesting and exciting. It sounds phenomenal, too. Up here the Oletha’s potency subtly changes its character into something even more boisterous and immersive, and something, which crucially, reveals a chassis that’s up to the job of matching the searing performance. It’s that which impresses the most, that, and the fact that this car, the product from the talented minds of a pair of ambitious, hugely qualified and committed driving brothers, is a first attempt. It would be an incredible car if BMW had built it, and it’s even more remarkable because Smit Vehicle Engineering has...

There’s a hint of American muscle over the usualBavarian culture, and it’s not out of place...