Mazda RX-8 SP

Remember those kids who always hung out at the bike shed at school? Those rebels who choofed down Winnie Blues, bragged about girls and compared battle scars from weekend BMX benders.


Even though you knew what they were doing was far from acceptable behaviour, they were oh-so-cool. And when – not if – they got busted, you still admired them for their ruthless arrogance and, even worse, envied the crap out of them if they still got top marks. Bastards.

In automotive terms, Mazda Australia is that rebellious genius which seemingly gets away with everything and, also, gets everything right. And it’s not by fluke either.

At the moment, the Japanese brand is blitzing the local market; its five-year-old Mazda 3 was the best-selling car in the country in January, and the new one, due next month, will no doubt give the traditional leaders of the pack a clip around the ear.

It’s also celebrating the 20th anniversary of the most successful sports car of all time, the MX-5, with a freshen-up, while the Mazda 6 , CX-7 and CX-9 are filling shopping centre carparks.

But then there’s its flagship RX-8: brilliantly engineered, sublimely balanced and surprisingly practical, yet ostracised as the geek’s sports car. When it first lobbed in 2003, Mazda banked on a one-size-fits-all model to try to attract a broader audience than the boy-racers that loved the RX-7.

But it was a bit soft for the core rotary fans and too quirky for the yummy mummy brigade. Not even last year’s facelift, debuting a more-focussed ‘GT’ with Recaros, Bilstein suspension and more aggressive visuals, could propel the it onto the just-gotta-have-one list.

And, we all you know why; it’s because the RX-8 just lacks the grunt turbocharged rotaries became renowned for. Sure, its revised twin-rotor spins to high heaven and its chassis is almost flawless, but the final FD Series RX-7 was just so damn good that it was, and still is, considered the ultimate RX. Seven years after being discontinued, the last RX-7 iterations still look modern and go like a cut cats.

There is, however, a solution to that little issue, and it all revolves around two letters – S and P. Not salt and pepper, but any Mazda with an ‘SP’ at the end of its name certainly has had a liberal dose of spice added.

Ask any Rotarian (not the community helpers, but die-hard fans of the Wankel engine) and the RX-7 SP is The King. You know, the school legend; the tough, good-looking, athletic braniac that won everything.

And this is where we come back to Mazda Oz as being those rebellious geniuses that hang out in the bike shed, because the SP programs are as homegrown as the GT HO Falcon, developed from a skunkworks operation led by its motorsport boss, Allan Horsley − and most of the time without full approval from Mazda’s Hiroshima HQ.

The RX-7 SP was primarily created to win the 12-hour production car races of the early 1990s (which it did) as a stripped-out, powered-up racer-for-the-road. Mazda Australia had to build 25 of them so the limited edition would be considered legal for the event, but eventually built an additional 10 to satisfy demand. Mazda also added the SP badge to its locally developed turbo MX-5, which was so good that the Japanese couldn’t resist doing its own (albeit softer) version.

Which brings us to the car on these pages. Mazda Oz and Horsley have done it again with a car that is so brilliant it could – and should – revive the SP badge. At the moment, this turbocharged RX-8 has been created to topple a super league of Supercars in next month’s Targa Tasmania road rally (see breakout). It all sounds too familiar really, doesn’t it?

But is this RX-8 good enough to wear the SP badge? Look back at everything Horsley has done during his 30-odd-year stint with the Japanese carmaker, and that question suddenly becomes completely redundant. The bloke doesn’t do anything by halves.

The pearl white RX-8 on these pages is actually the fifth turbo RX-8 he’s built, and had only just come off the dyno a couple of days before we drove it with the ‘development engine’ fitted. The full-house race engine is still being built, and Horsley is reluctant to give away any power figures before Targa − just in case it scares the beejesus out of the competition.

But you can bet it’s got at least an extra 50kW of grunt (making it around 220kW) and, more importantly, a shed-load more torque (potentially double the stock 211Nm) across a wider rev range.

What he’s done to achieve that is nothing short of amazing. Considering the engine is positioned so far back in the RX-8’s bay, almost every aftermarket turbo kit on offer has the snail mounted on top of the engine. But lift the lid and you can’t even see the blower. In fact, the only telltale sign that this is something special is the non-standard carbonfibre engine cover.

Horsley and his team have, somehow, managed to fit a custom-made Garrett turbo, on only 0.4bar (6psi) of boost, down on the side of the engine near the firewall, which means shorter intake and intercooler plumbing for sharper throttle response and better airflow for cooling.

The charged air is forced through a PWR intercooler into a custom intake and expelled via a 2.75-inch exhaust that, surprisingly, retains the standard cats and mufflers, but ends with two cannon-like tail pipes.

To help keep the system cool, there’s an additional turbo oil cooler and a lighter, less-restrictive radiator mounted behind the unique front bumper (both sourced from Japan’s Mazdaspeed) while the bonnet features custom air vents to help extract hot air from the engine bay.

Despite the extra power through the driveline, the six-speed manual gearbox has not been touched and still retains the standard carbonfibre propshaft, but there is a Torsen diff down the other end to further improve traction and handling. Not that a standard RX-8 really needed much in that department, but Horsley didn’t stop there.

For Targa at least, this car is fitted with a tailored suspension upgrade from former Australian rally champ, Murray Coote, that features fully adjustable, remote-canister dampers, stiffer and lower King Springs and lightweight 18-inch alloys wrapped in 235/40 semi-slick Dunlops.

The body has been stripped of as much sound-deadening material as possible and even with the addition of a full race-spec roll-cage, Horsley reckons its lost about 180kegs, which should have it at around 1200kg.

And, at Oran Park, where we gave the RX-8 SP its maiden run, the upgrades were immediately evident. I cranked the key and the boosted rotary idled smoothly but distinctly louder thanks to its bigger exhaust.

I had clear instructions from Horsley not to bend his beast, but conversely, to “treat it like any road test car you’d drive around here, and give it a go!” So I snicked it into first, gave it a blat and crawled down the pitlane with a fair degree of trepidation and excitement.

The first few laps were treated with an element of caution as the cold Dunlops were a bit skatey, but that allowed me to play with the engine under more normal conditions. And holy rotary does it work. Even under 2000rpm in fourth gear − normally the RX-8’s torque-less black hole − it picked up pace stronger than any Evo or STI, with minimal lag.

You wouldn’t even know it was blown – there’s virtually no turbo whine under load or wastegate noise when you step off the gas. It’s loaded with gobs of torque, more like a V8 than a highly-strung four-potter.

Except there’s no denying it’s a rotary when the needle soars into the stratosphere beyond 8000rpm with its unmistakable wail. And more so under a trailing throttle when it cracks, pops and probably shoots a flame or two of unburnt unleaded from the exhaust tips. It all reminds me just why I loved Allan Moffat’s Group C RX-7s so much as a kid.

With a bit more heat in the Dunlops, the chassis also came into its own. The standard RX-8 is already a benchmark for handling dynamics thanks to its near-perfect weight distribution, double-wishbone front-end, multi-link rear, torsionally strong backbone construction and the best electric steering in the business. Throw in semi-slicks, custom suspension and big Alcon front brakes and you really can’t go wrong.

The front will go precisely where you point it every time and offers more confidence than an African-American president, while the rear delivers the power to the ground without even a hint of tail wagging. Actually, trying to get the thing sideways for shooter Wielecki was the toughest task of the day; it has that much grip.

And that’s what it’s like straight out of the box, without any testing, tuning or tweaking. And, remember, the “race” engine is yet to go in it, which has to bode well for its chance to create an upset victory in Targa Tasmania and shake some of those supercars off the apple tree.

But, while that is its immediate aim, it would be such a waste if Mazda didn’t build a limited run of road-going SPs, even if it’s just as a turbo kit. It’s exactly what we’ve been crying out for from the RX-8 − the only ingredient missing and what the car should’ve been from the start.

And if you agree, then go and harass your Mazda dealer. Heck, give ’em a deposit or start a petition and send it to Mazda’s local HQ. Just don’t let this superb machine be a one-off racecar. That would be cruel.

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