Words: Alex Grant Pics: Matt Woods
Take it from us, building a fast Polo is tough. Volkswagen may have churned out a few swift versions over the years but, while the Golf received six cylinders, large turbocharged engines, durable gearboxes and four-wheel drive, Polo types were left with tweaked bits from the bottom of the parts bin, hardly any off-the-shelf upgrades and complicated conversions before we can really do any damage.
But it's not impossible, and a few do stick at it. They ignore the temptation to shift sideways into something (slightly) easier to build, and continue to make their lives tough until they get where they want. I guess it makes the end result a bit more satisfying, especially when you reach the top of your game and end up with something like Mario Thau's Polo 6N. This isn't only the fastest Polo in Germany, it's Europe's fastest front-wheel drive drag car and the first front-wheel drive VR6 in the world to crack the eight-point-something-second barrier over a quarter-mile! That's good going for a car which never left Volkswagen's quality control line with six cylinders, right?
Even Mario admits it's been a bit of a learning curve. In the eight years since he paid for its first run up a drag strip he's gone from being an enthusiast with a lightly turbo'd VR6 Polo as a daily to one of Europe's leading authorities on quick quarter-mile cars. He's also the brains behind Saxony-based Hidden Power
So let's get the obvious question out of the way: why stick with the Polo? With a relatively modern chassis, it wasn't as random a starting point as you'd expect. "I liked the Polo 6N because it looked fine and I still think so," explains Mario. "But the stock chassis is already pretty stiff compared to other cars, like the Mkl or Mk2 Golf. With the cage the car is now even stiffer and safer and it's made the car faster and easier to handle, too."
We first encountered this car at VW Action at Santa Pod back in 2012. It may have been in a slightly tamer state of tune but by spitting, banging and howling down the quarter-mile in under ten seconds on its first trip across The Channel it would've been hard to miss. It's been back every year since, with the VWDRC crew, and gets noticeably more competitive - not to mention capable of pulling bigger crowds - each time it smokes its way up to the start line.
Looking at what it's become, that first run in Luckau back in '06 was a turning point. While most of us would happy to put down a 12.374-second quarter-mile time at 123.39mph without any prior experience, Mario says it made him think differently about the car. The blown VR6 was clearly a good starting point but a shove of inspiration from the US drag scene started making him wonder how far he could go. "It was the sound of the VR6 that made me want one instead a 1.8T and it's very durable and a good source of power compared to other Volkswagen engines," he says. "So, yes, it was difficult to install, even with help from a friend who had done the same swap." Most of the engine hasn't changed since its first trip to Santa Pod but mainly because Mario got the basics right when he rebuilt it a year earlier. Having steadily upped the boost each season since 2006, in 2011 the 2.8-litre former Passat engine was machined to 2.9 litres with a flowed head and uprated internals ready to take an even bigger turbo.
An aggressive Cat Cams setup and Schimmel Performance inlet manifold - in itself claimed to give a 40bhp gain on a turbo'd VR -take care of getting that extra air through the engine, while the brain-rattling 100mm straight-through exhaust is a Hidden Power one-off. Impressively, despite the larger engine up front, the entire fuel system including the one-gallon fuel cell is tucked under the clamshell, leaving room for under-body aero with only the holes in the rear bumper as a hint.
With the engine out, the Polo gained its four-speed dogbox and sequential shifter, while solid driveshafts made from ultra-strong chromoly carbon-rich steel mean there's no risk of tearing them apart on a full-bore launch, however sticky the tyres and Tarmac are and however greedy Mario gets with its future power output.
But getting the turbocharger right was a bit more hit and miss, and he admits that this is the first season where it's working properly. The Polo had put down some solid performances in the mid-nines during the 2013
Mario moved onto a bigger Borg Warner turbo for 2014, and it looks like this may be the last piece of the jigsaw. He's tight-lipped about the exact spec, but paired with a new gearset it busted through the nine-second barrier at Bug Jam in July before heading back to Germany to set its current personal best at the Nitrolympx drag racing festival at the Hockenheim Motordrome a few weeks later. That's a personal best of 8.711 seconds and a closing speed of 176.98mph, despite traction issues.
At that pace, horsepower is a meaningless number. "It made 500bhp at one bar of boost in 2011, but I haven't checked the power on the dyno for years," he laughs. "It's not important to me - quarter-mile times are what counts. But it should be about 900bhp based on the last runs."
To put that into perspective, with a running weight of 968 kilos, the Polo has almost a 50% power-to-weight advantage over a Bugatti Veyron Supersport. The main difference is that the Volkswagen Group's fastest ever production car has twice as many wheels to put the power down.
Yet Mario's never had any ambition to divert any of that power to the back wheels: "You get used to the power very fast," he assures us with worrying calmness. "I built the car properly, and it runs straightaway. But the runs at the Nitrolympx 2014, with more power than at Santa Pod, were a bit funny. You could feel the difference in handling. Up to 1000 feet it has become hard work now."
Mario modified Golf VR6 suspension for the front end and stuck with uprated Polo parts at the back. The one-off kit is based on Koni dampers with modified valves and high-performance oil to take the stress of aggressive launches. It's set for hard compression at the rear and hard rebound at the front to limit squatting off the line and, yes, the wheelie bars are functional.
Tucked in behind the rear window is a parachute for emergency use, but the Polo uses Golf VR6 brakes, machined and using smaller discs to fit behind its 13" wheels. As with all quick Polos, hardware from elsewhere in the range is usually a base requirement.
Getting the kerb weight under a tonne meant an equally aggressive attack on the Polo's bodyshell, and it shows. Not only was the cabin stripped of everything made of fabric or plastic, but even the doors and rear hatch were robbed of their inner structure to shed a few more kilos. Aside from the faint whiff of E98 race fuel, there's nothing but a basic gauge panel, solitary bucket seat and steering wheel tucked inside the chromoly roll-cage.
But the exterior was a little tougher. There are no off-the-shelf parts to build a pro-spec Polo drag car, so Mario had to take care of the bodywork himself, including building that GRP clamshell. Modelled on the original steel panels, it weighs less than 6kg and improves
Plus it meant Mario could pick wheels to suit the spec, and shape the front end to fit. So the flared arches of the clamshell wrap around 9x13" three-piece Exospeed Star 8 wheels, in turn tucked inside the huge 24.5" Mickey Thompson drag racing tyres tasked with getting 15 times the car's original power output off the line.
He reckons he's finally got it working as it should: "It takes a lifetime to work on a car, you can always find something to improve. Besides the mental process to find a setup thats fits, the most challenging part was to find and develop a good working drivetrain. Apart from the turbocharger we haven't had bigger problems with it since 2011."
But he's just as conscious that the scene moves as quickly as the cars themselves. Having broken records without perfect traction, he's got a few ideas for the winter before hauling the Polo back to the UK next summer to give it a run on sticker Tarmac.
"I have some changes in mind, which I'm going to start on soon. Because I had traction problems up to 330 feet at the Nitros, I am excited to see what can happen when traction is as good as it was at Santa Pod," he says.
So between the jet cars, race bikes and ordinary punters hacking down the quarter-mile in Northamptonshire next year, keep an eye out for Mario's fourth return to the Pod. Set on raising the bar for the rest of the scene, treat this as a reminder that sometimes it's more fun not to take the easier route •
ENGINE: 2.8-litre Passat VR6 engine, overbored to 2.9 litres by Hidden Power, custom-made PAR billet con rods, modified crank, machined cylinder head, cams and springs from Cat Cams, Schimmel Performance Short Runner inlet manifold, Borg Warner billet turbocharger modified by Hidden Power, custom front-mount intercooler and pipework with Samco hoses, custom-made 100mm centre-exit exhaust, Lugtronic ECU mapped for E98 race fuel, one-gallon fuel cell mounted in inner wing, 360l/h Pierburg fuel pumps (x2), Aeromotive fuel pressure regulator, Injector Dynamics ID2000 2000cc injectors, Fluidampr pulley with vibration damper, Hidden Power lightweight race battery, four-speed drag dogbox with Hidden Power custom gear set, sequential shifter, Sachs RCS twin-disc clutch, custom flywheel and cover, solid chromoly driveshafts
SUSPENSION: 9x13" (front) and 4x15" (rear) Exospeed Star 8 wheels with 24.5/9x13 Mickey Thompson Drag Slick tyres (front) and 22.0/3.5x15 M&H Racemaster Drag Slick tyres (rear), modified Golf VR6 (front) and Polo 6N (rear) Koni suspension with adjustable rebound and compression, uprated valves and heavy-duty oil, Golf VR6 front and rear brakes modified to fit under 13" wheels, Stroud Safety brake parachute
OUTSIDE: GRP front clamshell including wings, bonnet and bumper, Polycarbonate side and tailgate windows, Polo 16v rear bumper with aero holes, wheelie bars, custom sump and aerodynamic floorpan guard, custom roof spoiler, fibreglass tailgate, wing mirrors, tailgate handle and fuel flap deleted, all metalwork painted Volkswagen gelbgrun
INSIDE: All interior trim and dashboard removed, inner door and tailgate skins cut out, custom instrument panel with RaceTech gauges, six-point chromoly roll-cage (painted black), fixed bucket seat and harness
SHOUT: Kevin Black at Lugtronic, VRS Northampton, Turboscheune.com and my team
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