V8 MX-5, Anyone?

You can't complain that this Mazda MX-5 has no grunt. It's got a 391kW 6.2-litre LS3 V8

by BRIAN MAKSE pics TRAVIS INGRAM

EFORE I arrived, I hadn’t heard of Palisade, Colorado. It’s a small town in the high desert near the Utah border and set humbly among the peach orchards is a little company called Flyin’ Miata that’s known for getting the most out of Mazda’s roadster. Since the launch of the original MX-5, they’ve been developing all of the crazy things – turbo kits, superchargers, even stuffing V8s under the Mazda’s bonnet.

The latest generation ND MX-5 is here and Flyin’ Miata already has a complete range of tuner parts. But what’s most interesting is they’ve already managed to fit a 391kW, 6.2-litre LS3 small-block in one. They call it the Habu, after an Asian pit viper.

While there are parallels throughout the history of sports cars where someone had the wild idea to take a small car and drop in a big motor, this is 2017 and this new MX-5 brings a full set of considerations. For starters, the MX-5’s systems communicate to one another through a CAN bus, making an engine swap more challenging than ever before.

What’s more, the V8 conversion necessitates swaps of other major components, further complicating matters. The Mazda gearbox is replaced by a Tremec T-56, the differential is new, and so is the hydraulic steering rack, all procured from the fifth-generation Chevy Camaro.

You might imagine the V8, transmission and diff are a difficult fit for the ND, but other than massaging the firewall and reinforcing the front and rear subframes, it all goes in quite easily. No cutting or chopping of the MX-5’s chassis required.

On the other hand, persuading GM components to talk politely with Mazda’s systems is difficult. Flyin’ Miata turned to an unlikely specialist – one that deals with mining equipment – to fix the integration.

After a tremendous amount of development, the Habu’s systems operate as in a regular MX-5 – the climate control functions perfectly, as do the gauges, while the abysmal satnav functions as intended.

Flyin’ Miata leaves two systems out of the V8 conversion – stability and traction control – removing the electronic nannies and making the Habu a machine for purists. ABS is retained, but otherwise it’s you and your skills, the way it should be.

While the first development car is still having a couple of electronic niggles remedied, the first customer build is under way (with a 429kW Lingenfelter-sourced V8, because 391kW feels asthmatic pulling an 1180kg roadster...). Flyin’ Miata also offers a 321kW V8, primarily to satisfy Californian emissions legislation.

Despite the radical surgery it’s unmistakably an MX-5. The dimensions are the same over a near-stock stance only altered by massive Bridgestone rubber on custom wide wheels. It isn’t excessively low and the subtle roll bar barely hints that a monster engine lives here, though for fun the team replaced the SkyActiv marker with a $10 LS3 badge from eBay.

Similarly, the interior can also be mistaken for

They’ve managed to fi t a 391kW, 6.2-litre LS3 small-block. They call it the Habu, after an Asian pit viper

Controlling Habu’s attitude takes little more than a caress of the pedal and it's matched by a glorious howl

original. There’s a new steering rack, but the Mazda airbag wheel is unchanged, while only MX-5 nerds will notice the shift knob sits a little differently.

Then you hit the start button and the V8 thunder reminds you of something bold and brash from HSV.

You can’t help but laugh as the promise of the looks melts away. There’s real heft to the controls. Where the MX-5 feels light and lithe – through the controls and the seat of your pants – the Habu is like driving a scaled-down Corvette. A faster, rawer Corvette.

The steering feedback delivers the wonderful analogue quality that’s so rare today, and it’s quick enough to catch oversteer or perhaps even balance a graceful drift. It requires more input than the MX-5’s electrically assisted steering, but that matches the other control weights. The clutch and shifter are far from delicate. The Tremec T-56 ’box’s shift action is direct and mechanical, requiring about twice the Mazda’s shifter effort.

The brakes have received a modest Wilwood upgrade, the rear rotors are retained and clamped by four-piston calipers while the fronts feature larger 325mm two-piece rotors and six-piston calipers – more than any circa 1200kg car could ever need.

The conversion adds nearly 120 kilos to the MX-5, but while the additional mass contributes to the Habu feeling different, more substantial, it doesn’t upset the MX-5’s wonderful balance. Flyin’ Miata says the front-to-rear weight balance has changed by less than three per cent, and I’d say the suspension package makes up for it. The new set-up is light years ahead of the original equipment and better suited to tame massive power.

Mazda designed the ND with relatively long suspension travel for a roadster, and Flyin’ Miata took full advantage. They believe that for suspension to work it needs travel, and damper supplier Fox agrees.

Better known for mountain bike and off-road truck shocks than sports car applications, Fox has been working with Flyin’ Miata for some time and what you see is an MX-5 that’s been modestly lowered over its wider wheels and rubber. Ride quality, body and wheel control are all surprisingly superb; without question, these are some of the finest conventional dampers available.

Grip from the track-spec Bridgestone RE-71R tyres is exceptional. At 245/40-17 all around, they’re mounted on nine-inch wide 949 Racing wheels engineered specifically for this car.

The Flyin’ Miata/Fox suspension excels everywhere, road or track. The limits are quite high – the Habu will reportedly pull more than 1G laterally – but it remains approachable all the way to those limits.

With outstanding ride quality and wheel control, as well as the fine overall balance at or even beyond the limits, this is a car that taunts you into going faster and faster through the turns. It’s a combination from the heavens – a controllable and predictable chassis with remarkable feel.

Driving this tiny package, the 6.2-litre LS3 GM crate motor is simply magnificent. As well as the impressive 391kW there’s 663Nm on tap, and a throttle response that can only be described as crisp, so controlling the Habu’s attitude takes little more than a caress of the pedal. And it’s all accompanied by a glorious howl wherever you are in the rev range.

What that translates to is the Flyin’ Miata ND Habu claiming 0-100km/h inside four seconds and

It’s a sports car that will put a smile on your face every time, whether on road or the racetrack

How To Get Your Hands On One

This crazy conversion is left-hand drive only – for now FLYIN’ Miata has been supplying turbo, supercharger and V8 kits for a long time. It’s sold far more kits than it’s installed in-house.

The ND’s chassis is surprisingly well-suited to a small-block conversion and the drivetrain fits with just two mild firewall modifications to the firewall.

The Camaro diff also fits the rear subframe nicely, as does the (LHD) steering rack up front. Both subframes get some reinforcing, and the driveshaft and axles are custom-fabbed.

Naturally, the brakes, wheels and tyres are an easy install.

So far, so good. But integrating the GM components into the Mazda’s CAN bus requires a lot more work and for the time being, if you have your heart set on owning a Habu, you’ll have to send your MX-5 to Colorado, USA. Hopefully a conversion kit will one day happen.

Fortunately, Australian ND owners looking for more power are treated to local turbo kits, in mild or wild specification, like the tidy kit offered by specialists Tunehouse in Sydney.

stomping the quarter-mile in less than 12.

So just as the added mass of the conversion has changed the handling, so the driving experience is equally more substantial. It’s recognisable yet doesn’t feel like a Mazda at all.

Of course, all this added goodness comes at a cost – US$50,000 (AUD$66,000) on top of the donor MX-5.

Even so, there’s nothing like it – there’s nothing as raw and visceral as the Habu for the price.

Flyin’ Miata is currently nearing a solution for right-hook MX-5s – the challenge has been sourcing a compatible steering rack – but by the time that’s resolved, any of us crazy enough to drop a V8 in an MX-5 will also get to choose between the soft top or the new RF.

The Habu is an over-the-top roadster. But while it has enormous performance, it also rides comfortably enough that you and your passenger won’t be fatigued after a road trip. Smaller and much more wild than a Corvette, it’s a sports car that will put a smile on your face every time, whether on road or the racetrack.

FLYIN' MIATA MAZDA MX-5

BODY 2-door, 2-seat roadster DRIVE rear-wheel ENGINE 6162cc V8, OHC, 16v BORE/STROKE 101.6 x 92.0mm COMPRESSION 10.4:1 POWER 391kW TORQUE 663Nm POWER/WEIGHT 331kW/tonne TRANSMISSION 6-speed manual WEIGHT 1180kg SUSPENSION (F) A-arms, coil springs, anti-roll bar SUSPENSION (R) multi-links, coil springs, anti-roll bar L/W/H 3915/1735/1230mm WHEELBASE 2310mm TRACKS 1494/1505mm (f/r) STEERING rack-and-pinion BRAKES (F) 325mm solid discs, 6-piston calipers BRAKES (R) 280mm solid discs, 4-piston calipers WHEELS 17.0 x 9.0-inch (f/r) TYRE SIZES 245/40 R17 (f/r) TYRE Bridgestone RE-71R PRICE AUD$66,000 (excluding donor car) PROS Extra grunt; retains handling; soundtrack CONS Not available in Australia; not a cheap exercise STAR RATING 11112