Up close and personal with Rhys Millen’s wildest creation yet.

One hundred and eighty-two miles per hour. Two hundred and ninety-three kilometres per hour in our money. Mathematically, that’s how fast it will go according to Rhys Millen Racing (RMR) team manager Eric Cantore as he lifts a roller door at the back of RMR HQ. “Gearing won’t let it go any faster,” he says. The dust cover comes off and the world’s wildest Hyundai Genesis Coupe (bar perhaps the drift car parked up next to it) is revealed.

It might be a world away from the automotive glitz of the SEMA Show in Las Vegas, where just days before it had made its public debut, but the coupe looks every bit as staunch under the unflattering light of the workshop’s fluorescent tubes. The whirr of race fuel pumps consumes all attention and seconds later the roar of more than 500hp erupts from the twin rear mufflers. The concept codenamed ‘RM460’ is alive and very real.

There’s a certain quality to this Coupe concept. Not its build, which like everything that tends to emerge from the depths of the Rhys Millen Racing lair is absolute world class, but how it’s been built.

This is an extreme machine wrapped in real-world bodywork — exactly what was envisaged when the RM460 was little more than a pencil sketch on paper.

“We wanted to show the world what RMR and Hyundai are capable of,” Eric explains. “This is our version of a 500-plus horsepower Hyundai supercar.”

To achieve that goal the finished product had to be instantly recognisable as a Genesis, but customised enough to set it apart from stock siblings. To tick the supercar box, however, its powerplant needed to be moved from its factory position in the front of the car to a rear mid-mount, and a few more cylinders were required too. RMR had a grand total of eight weeks to get it all done. Nothing like a bit of pressure.

Millen and his engineers are well versed in the art of custom builds ­— that’s evident in the ex-pat Kiwi’s arsenal of competition craft. His most recent has been the Red Bull-sponsored Genesis drift car, which did double duty last year and drove across the line for a new class record at the famed Pikes Peak international hill climb. The RM460 build is a little different, though, as it was built for the road rather than the racetrack — much in the same way that Rhys’s celebrated father, Rod, completed the ‘Celica Ultimate’ concept build in collaboration with Toyota’s TRD division back in the early ’90s. A challenge like this is ingrained in Rhys’s DNA.

The build began when Hyundai dropped off a brand spanking new Genesis and a bunch of components. One of the most important was the TAU 4.6-litre V8 engine, as found in Hyundai’s flagship Genesis sedan.

If you think changing the position of a car’s engine from front to rear sounds like a big job, you’re right. RMR has made it look easy. Surprisingly, the Hyundai still uses its factory rear subframe arrangement and factory subframe pick-up points, and the car weighs no more now than a bone-stock sub-1500kg Genesis coupe.

The engine itself required little in the way of modification to bring it up to spec. The Hyundai TAU V8 shares many similarities with Toyota’s famed 1UZ mill, being alloy and featuring DOHC 16V heads above each cylinder bank. Internally the only upgrades were a switch to 11:1 compression JE forged pistons. The OEM crank was lightened but the rods are factory fare. However, to increase performance the intake and exhaust systems were completely revised.

On the fuel side, a pair of Bosch Motorsport 044 competition fuel pumps supplies the eight 480cc RC Engineering injectors plugged into eight individual RMR throttle bodies running open trumpets.

The juice is stored in a Fuel Safe cell mounted in the empty engine bay at the front of the car.

As for the work of art that is the exhaust, it features a pair of custom RMR stainless steel headers running into 304 stainless steel pipes and twin RMR stainless steel rear mufflers. Because the RM460 was engineered to be 100 per cent street legal there’s a pair of ceramic catalytic convertors. Although the car has yet to be strapped to the dyno, Eric’s confident the tuned TAU mill is outputting numbers in the region of 550hp to 600hp — a good step up from the 375hp it generated out of the crate.

Getting it all to the ground is a Mendeola S-5 transaxle transmission. That fits in neatly behind the engine and provides direct drive via its Mendeola LSD to the rear wheels through custom shafts.

The sequentially shifted 5-speed trans runs a Kennedy twin-plate sintered clutch for street-friendly operation.

That theme continues through to the interior, where extensive use of Alcantara and a sprinkling of carbon fibre make the RM460’s cockpit a very pleasant place to be. You’d think that with an engine right behind you it would be hot and noisy, but thanks to some well thought-out sound and heat insulation it’s not at all, even when the engine’s working hard at speed.

With its RMR Signature Edition bodykit, custom carbon fibre work and fresh-squeezed BASF Candy Max Orange paint, the RM460 is the complete car it was envisaged to be. And better still, with its angry engine, everyway adjustable KW suspension and tuned StopTech brake system, it gets the job done as it should.

It’s still amazing that RMR was able to get the whole job completed in such a short space of time, and to such an exacting standard. But according to Eric, short lead times are always the way it is with SEMA builds. Rhys Millen Racing put in the wrench time, now it’s just up to Hyundai USA to put this bad boy into production. Where do we sign up?

2010 Hyundai Genesis Coupe RMR460 – Specifications

Engine: Hyundai TAU 4.6-litre alloy V8 DOHC 32V, JE 11:1 forged pistons, lightened factory crank, factory rods, RMR 8x throttle bodies, 480cc RC Engineering injectors, 2x Bosch Motorsport 044 fuel pumps, Fuel Safe racing fuel cell, custom RMR stainless steel headers, 48mm mandrel bent 304 stainless steel exhaust system, 2x 4-inch ceramic catalytic convertors, 2x RMR stainless steel rear mufflers, front-mounted TAU V8 radiator, 2x electric fans, AEM Version 2 engine management system, Goodridge lines/fittings, carbon fibre engine bay panels
Driveline: Mendeola S-5 5-speed sequential transaxle transmission, Mendeola LSD, Kennedy twin-plate sintered clutch, lightened factory flywheel, custom Driveshaft Shop drive shafts
Suspension: KW Variant 3 adjustable coil-over shocks/springs, RMR sway-bar kit, custom RMR rear subframe, urethane bushes
Brakes: Front – StopTech Trophy Sport 6-pot callipers, 355mm slotted rotors, StopTech pads, Rear – StopTech Trophy Sport 4-pot callipers, 345mm slotted rotors, StopTech pads
Wheels/Tyres: HRE 560 Series 20×9-inch front, 20×10-inch rear, Toyo T1-R tyres 255/35R20 front, 285/30R20 rear
Exterior: RMR Signature Edition bodykit, carbon fibre rear engine hatch, diffuser, carbon fibre side vents, carbon fibre mirrors, BASF Candy Max Orange paint
Interior: Sparco Chrono Sport seats with Alcantara upholstery, custom trimmed headlining, custom trimmed door panels, factory Genesis steering wheel with carbon fibre trim, Remark Industries gear selection meter, Infinity Kappa Series speakers, Infinity Kappa Series amplifiers
Performance: Dyno Power – estimated 500hp @ wheels

Rhys Millen – Driver Profile

Age: 37
Occupation: Professional driver & owner of RMR
Previously owned cars: Mazda RX-3, Toyota Supra, Mitsubishi Lancer Evo VI.5, VII, VIII, Pontiac GTO (drift), Pontiac GTO twin turbo, Pontiac Solstice (drift), ’39 Chevy Pick Up Trophy Truck (Baja off-road), custom Dukes of Hazzard Harley-Davidson
Rhys Thanks: Hyundai, JE Pistons, KW Suspension, RC Engineering, Sparco USA, Infinity Audio, Mendeola Transaxles, HRE Wheels, Toyo Tires, HeatShield Products, AEM, StopTech Brakes, BASF Paints

Words: Brad Lord Photos: Alastair Ritchie