TH2 RS-Berlin Airlift Most of the German tuner cars that turned up at this year's Nardo event would give any enthusiast wet dreams, but the contender that raised my eyebrows the highest for its sheer ingenuity was a van.
I noticed the TH Automobile TH2 RS on the afternoon I arrived, when we assembled in one of the garages for a sandwich. Cars taking part in the event are kept undercover in two adjoining garages overnight, and as I was standing around in one of them chatting with the tuners, I heard the familiar deep growl of a tuned Porsche Turbo exhaust.
I turned around expecting to see a sleek be-spoilered 911, but instead got an eyeful of Kermit green VW T5 bus backing into the garage. It was one of those situations where the brain either goes into overdrive or shuts down completely.
Mouths hung open as the green bus came to a halt. The driver moved over from the centrally positioned driver seat, opened the door and smiled as he got out. Then he casually walked around to the other side and opened the side door to give us a better view of the interior. What followed was like the mountain scene from Close Encounters of the Third Kind as everyone peered inside. At that point, he could have walked straight past us waving gold ingots and nobody would have noticed.
Stripped out and clad in lightweight side panels, with five lightweight carbon race seats, the interior was otherwise as bare as Mother Hubbard's proverbial cupboard.
The central driving position takes its cues from the McLaren F1, the instrument pack is Porsche GT3, and the dashboard is a bespoke molding, created at great expense to match the high quality of the rest of the van, whose new front end even has bi-xenon lights.
I collared Sven Thomsen, owner of Berlin-based TH Automobile, whose company specializes in the installation of Porsche 996 and 997 mechanicals in VW T4 and T5 vehicles. Thomsen explained that because the boxy VW T5 bus has nearly twice as much body area as a 911, it is not immediately obvious that the green paintwork is the hue applied to the current Porsche GT3 RS. Its black-painted 20-inch alloys mimic the GT3 RS look too, as do the twin centrally positioned exhaust outlets.
Apart from the obviously expensive interior work, the T5 shell has been the subject of extensive re-engineering to convert it from a front-engine, front-drive configuration to accept the rear-engine, rear-drive Porsche 996 GT2 drivetrain and some Porsche suspension elements.
Unlike both the stock T5 and the GT2, the TH2 uses air springs made by a Dutch company, coupled to H&R dampers and a ride-height lift system. The ECU lowers the ride height in two steps for better handling and aerodynamics.
For Nardo, TH recalibrated the suspension ECU to lower the front end by 30mm over 220 km/h (136 mph). This reflex camber setting reduces lift over the front axle as well as drag.
The basic engine is 996 GT2, tuned by 9ff to the same spec as the motor in the 9ff 9f-T6 that ran to 372.2 km/h (232.7 mph) at Nardo in 2004. Back then, this engine made around 750 hp at 6590 rpm with 622 lb-ft of torque at 6000 rpm, but the TH2 has a more advanced camshaft grind and some other small mods to up the big numbers to 800 hp and 664 lb-ft of torque.
9ff's Jan Fatthauer explained that his team built the engine for TH Automobile, where it was installed. The vehicle was then returned to 9ff for a custom exhaust system and ECU mapping.
The gearbox is GT2 with an uprated clutch, and a dual mass flywheel to retain comfort. Fifth (0.85) and sixth (0.71) ratios are very high for top speed and economical cruise. However, like the previous generation Corvette, sixth is so tall that top speed is reached in fifth. Stopping power comes from big brakes, 390mm discs with six-pot calipers in front and 365mm discs with four-pot calipers at the rear.
"The radically different vehicle weights and gear ratios meant a unique program for the ECU," Fatthauer explains. "Also, TH's bespoke water and air-cooled intercoolers do a good job of lowering intake temperatures, but have a bit more back-pressure than ours. Because of this we had to run 1.4 rather than 1.3 bar boost for the same power. The turbochargers are our KKK hybrids that are built from a combination of K24, 26 and 29 parts and are a 9ff exclusive." Because the T5 is almost 900 pounds heavier than the GT2, it needs more torque low down, but with 1.4 bar of boost tuned to deliver 900-920Nm, this isn't really a problem.
Despite its blunt shape, the TH2 exceeded all expectations at Nardo and screamed around the banking at 194.2 mph (312.5km/h). That's 1.19 mph faster than the latest 997 Turbo.
The next step in TH Automobile's journey to build the ultimate VW bus will be 4WD. The choice is between using 996 Turbo running gear or splicing the Porsche power train with VW's Synchro AWD system. Watch this space!
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Sam @ Bayford VW
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