Our first encounter with German VW tuner HGP was at the Continental Tire top-speed shootout at Nardo in 2007, where the company’s twin-turbo Golf R36 ran to a spectacular 327.6 km/h (204.75 mph) before its unmodified DSG gearbox gave up the ghost under the sustained onslaught of 543 hp. When you consider that Nardo’s banking scrubs a few mph from a car’s true top speed, this totally street-legal Golf is probably capable of a genuine 207 mph on a flat autobahn in neutral wind conditions.
The next encounter was in a recent issue of Germany’s Auto Bild Sportscars magazine, where the HGP twin-turbo Golf 530 RS went head-to-head with a stock 500-hp Porsche Turbo PDK at the Sachsenring racetrack. Normally, a tuned hot hatch has no chance of matching a similarly powerful Porsche Turbo on a timed lap, but the HGP Golf recorded exactly the same 1:36.86-second lap time. The Porsche may have reached a higher terminal speed on the long straight, but the two cars had the same average speed of 136.44 km/h. Because there is no R32 version of the current Mk 6, HGP grafted Mk 5 R32 mechanicals into the newer shell, and then added its own twin-turbo kit. Why? Because you can get more power out of a twin-turbocharged V6, and because like us, HGP’s staff prefers the spine tingling V6 engine note to the flat drone of the four-cylinder 2.0T.
However, unless you are prepared to spend a lot of money having HGP build you a replica of this car, the fastest HGP cars will now be based on the new Golf R and Scirocco R models. The white Golf R I’m driving today is the development car to which HGP’s affable founder, Martin Graf, has just fitted his latest power upgrade kit. This conversion is still a couple of months from being signed off, and there are wires for test instruments hanging out from under the dashboard.
Graf would normally never let a car undergo a press evaluation until it is completely ready, but in this case, let’s just say that a certain amount of arm-twisting was involved.
What I said previously about the latest 2.0T FSI motor being incapable of matching a twin-turbo V6 is simple physics. As the saying goes a good big ’un is always better than a "good little ’un." Even so, the 460 hp that results from HGP’s comprehensive upgrade is nothing to be sniffed at. For a car that’s not quite finished, the HGP Golf R looks and feels very up and together. You only have to look at the thought that went into the design of the new components and their sheer quality to see that HGP is a company that takes the position and quality of every last nut and bolt very seriously.
To make this clear, Graf shows me the sand-cast alloy intake manifold, larger high-flow intercooler and hybrid turbocharger with high-nickel content cast-iron exhaust manifold. He then uses the silicone hose sections to connect these components around a mythical engine to show me how the new breathing arrangements work.
"The final piece in the puzzle is our in-house ECU remap that makes everything work as it should," he adds. While many tuners farm out ECU remapping, this is something Graf does himself. "I work with OEM equipment and application software and am online to Bosch," he says. "It is easy to work with Bosch ECUs, but the new Siemens ones are a problem."
The stock Golf R motor makes 265 hp and 255 lb-ft of torque from a tuned version of the motor from the Golf GTI Mk 5 rather than the latest Mk 6. The cylinder head is modified and uprated pistons, connecting rods, high-flow injectors, larger turbo and intercooler fitted.
"Using that as a basis, we lower the stock 9.8:1 compression ratio to 8.6:1," Graf says. "There are two ways of doing this, the expensive way being to replace the pistons with new low-compression ones, which involves a complete engine rebuild."