Kiwi built Quattro S1
Interesting Read over at Speed Hunters
We love the Quattro so we thought we’d share it with you guys!
The 1980s are remembered for a lot of things, but in the motorsport world those years represent the golden era of rallying. Group B took the World Rally Championship and turned it on its head. In matter of just a few short years factory-backed cars had doubled their power output and were packed full of cutting edge technology and exotic components. Many people likened them to Formula 1 cars for the gravel, and that wasn’t far from the truth. But they were too fast and ultimately too dangerous, which is why we will, unfortunately, never see anything like Group B in the WRC ever again. The spirit, however, will always live on.
With such small numbers of competition cars built during the heyday, owning a pukka Works-spec machine is a privilege that only few can enjoy. Most surviving cars are in collectors hands and subsequently don’t come up for sale very often. And when they do there’s the small matter of price, which is anything but. So what to do if you crave a slice of Group B, but can’t lay your hands on the real thing? In the case of Kiwi rally driver Andrew Hawkeswood, you simply build one yourself.
As far as Group B replicas go, Audi’s Quattro S1 is one of the simpler to execute given the fact that the cars were essentially built from production car base, rather than steel tubes. The Audi also retains its engine in the front rather than the back, as was the case with cars Lancia Delta S4, Peugeot 205T16 and the Ford RS200.
That’s not to say that it was an easy build in any respect, but owning his own race and rally preparation workshop (Force Motorsport), and employing a small but highly talented team of engineers, definitely made the job a whole easier.
But what emerged out the other end is something very cool. And with close to the same amount of power as a genuine works car, it’s certainly not the shy, retiring type. But as you’ll soon find out, there’s a lot more to this car than first meets the eye.
Like the real S1 deal, considerable body modifications were required to give the car the correct proportions. Unlike regular showroom-spec Audi coupés of the era, the rally cars (and the 200 road going versions required to be manufactured to satisfy Group B regulations) were 12.6 inches (320mm) shorter. Compare the shot above to that of a run-of-the-mill coupe and you’ll immediately notice the different in the length of the rear side windows. Effectively, the modifications transformed the car from a coupé into a hatchback and with the alteration a more suitable wheelbase for the quick direction change requirements of rallying. However, coupled with power outputs that exceeded 500 horsepower, they certainly weren’t easy to drive. Just ask Walter Röhrl.
There is one anomaly with Andrew’s car and that’s the windscreen’s rake. During Audi’s early efforts with the Quattro, works drivers complained that the front windscreen was prone to light glare, so the Sport Quattro versions were fitted with a shorter screen (on a more acute angle) borrowed from the Audi sedan.
For the most part, though, with its Germany-sourced S1 replica body kit and an S1-style bonnet and rear wing handcrafted in New Zealand added into the mix, the Audi certainly looks the way it should. Dig a little deeper, however, and you’ll find that all is not as it seems. Because while most – if not all – S1 replicas use Quattro all-wheel-drive, this particular car has the underpinnings of a V9 Subaru Impreza WRX STI.
If you’re scratching your head and asking “why”, Andrew makes a good case. Firstly, the car began life not as an all-wheel-drive Quattro variant, but a poverty-pack front-wheel-drive ‘GT’ purchased for the princely sum of NZ$23 (US$20), meaning that a 4WD system of some description needed to find its way up and under the bodywork. Secondly, there’s the performance factor. Aftermarket parts like the Cusco limited slip diffs fitted are plentiful, and using the compact WRX STI six-speed gearbox (well, the casing anyway – it’s since been fitted with a PPG straight-cut gear kit) would allow an engine to sit much further back in the car.
Initially the idea had been to build custom subframes and install the Subaru driveline that way. But once Andrew and his team got into the build, they quickly realized that it would be a much easier proposition to cut out the Audi’s floorpan, and replace it with the floorpan from the STI – albeit modified for width and length. To fit the engine to the WRX transmission necessitated an adapter plate and a custom subframe to allow it to clear the Subaru steering rack. But out the back the subframe is Subaru OEM.
Part Audi, part Subaru, but it works.
According to Andrew, when people learn that the car has a Subaru driveline they usually assume that there’s a boxer engine ticking away up front. Of course, that would never cut it.
Only one engine was ever going to do, and that’s an Audi-bred inline-five with a DOHC 20V head. I’m not sure what it’s like in Europe, but in this part of the world finding an ‘RR’ engine isn’t all that easy. Only three 20V Quattros were sold new in New Zealand, and to get his hands on this engine Andrew had to purchase a complete car. In standard form the 2.2L five produces reasonable power, but for what Force Motorsport had in mind the bottom end was pulled apart and rebuilt for rally duty with Wiseco forged pistons and heavy-duty rods. Up top the 20V head benefits from a full race-prep and features custom cams and oversized valves.
The turbocharger is by custom T3/T4 turbo crafted from a Garrett GT3076 with boost controlled through the engine’s OEM external wastegate. As you can see if this photo, the turbo is currently fitted with a 36mm restrictor in the inlet, which is a mandatory fitment for turbo cars running in New Zealand’s new Rally Xtreme Challenge. Of course when Andrew’s not rallying the Audi in the series, it quickly comes off allowing the engine to breathe as it was originally intended to.
On the intake side of the engine is an aluminum manifold complete with individual runners fabricated in-house at Force Motorsport. The Works-style design was settled on after a long time spent studying photographs of S1 engines. To allow for increased airflow the manifold breathes through a Mitsubishi 4G63 throttle body that’s fed cool air through a front mounted air-to-air intercooler. Injectors are Sard 800cc units that supply an exclusive diet of E85 fuel.
Of course the engine is just one piece of the puzzle. To make the most of the power, the Audi runs a custom-built suspension set up courtesy of Australian motorsport specialist, MCA Suspension.
One of the most important aspects of a rally car, the brake system, has been suitably upsized too and now features Alcon calipers and slotted two-piece rotors front and rear.
Andrew never had any intentions of recreating a cluttered Works Quattro S1 office space with period fittings. Instead, the interior space is basic but functional. The pedal box – and the firewall it’s attached to for that matter – is once again WRX STI fare.
It’s a quality fit-out too; with an extensive rollover protection and Sparco Evo FIA race seats fitted with Willans FIA harness seat belts.
Of course there’s a hydraulic e-brake for hairpin turns, too. Anyone who has seen Andrew drive will know that he’s definitely mastered the art of pivoting the Audi 180 degrees while keeping the wheels engaged in a spinning frenzy.
The sum of all the parts has created arguably one of the coolest classic rally cars in New Zealand – it’s certainly the most spectacular.
There are two things I really love about this car. The first one: it’s 100 per cent street legal in New Zealand, as it needs to be for rally touring stages. As with any modified vehicle (legally) on the road the Audi had to be inspected and signed off by an accredited LVVTA (Low Volume Vehicle Technical Association) engineer. The ‘Cert’ plate lists all the main modifications, which in this case are numerous.
The other thing? That’s the fact that Andrew uses it exactly how you’d hope to see a real Quattro Group B machine used. Sure, there are tidier and more ‘correct’ S1 replicas on the planet, but I’m not sure if any of them are driven quite as hard in proper rally competition as this one is. Mechanical sympathy does not live here.
For the past two years Andrew has been at the top of the competitor guest list at Rod Millen’s Leadfoot Festival. And with the turbo restrictor removed, he hasn’t wasted the opportunities to drive at ten-tenths up the immaculately groomed 1-mile long driveway. Sometimes it’s quicker to fly though!
When you see the Audi in its natural habitat, it’s like winding the clock back to the mid ’80s. And the sound… let’s not forget that unmistakeable sound!
It might not be the ‘real’ thing, but this is one car that’s certainly helping keep the Group B spirit alive.
– Brad Lord