All modifications had to have TÜV approval for legal road use. In Germany, every single part that goes on sale, even a gearknob, has to be tested and certified by the TÜV authorities to guarantee perfect fit and safety in operation. This also means an exhaust no louder than 95dB, 5dB more than EU factory production standards.
In addition, tricky track-day rubber like the Michelin Sport Pilot Cup, Dunlop Super Sport Race, Pirelli P Zero Corsa, and Yokohama A048 was banned from the road legal classes.Of course every tuner likes to show what he can do in the way of ultimate spec, especially since some customers want cars specifically aimed at track use. Thus, a new Open Class was introduced for such cars, which could use the super-sticky track day tires.
Class 11 Winner:
MTM Motoren Technik Mayer GmbH
The format is practice sessions on Friday afternoon and the event proper on Saturday morning, with the Drift Challenge after lunch. The event was originally divided into half a dozen classes. But as the age of the performance SUV and turbodiesel dawned, more classes were added, and coupes and cabriolets were also split off.
There are now separate classes for naturally aspirated and forced aspirated sedans, while the kafuffle over the street legal issue spawned the Open Class, where anything goes.
Class 7 Winner:
MTM Motoren Technik Mayer GmbH
Also new in 2004 was the SUV class for tuned off-roaders, which fit the then new Porsche Cayenne perfectly. In fact the Cayenne continued to dominate this class in the years to come.To make sure they get the best results, almost all the teams hire professional race drivers to pilot their cars in the Tuner GP. Big names like Jochen Mass, Nick Heidfeld, Roland Asch, Kurt Thiim, Claudia Hurtgen, and Wolfgang Kaufmann have figured in the lineup.
Given that professional race drivers should be within half a second of each other on the same track in the same car, the raw data also gives us a fair baseline to compare how much quicker a modified car really is over the standard issue.
Class 14 Winner:
The weather certainly plays a big part in lap times. It has only rained three times in the Tuner GP's history, but it's worse if it is dry for the practice session on Friday and rains on Saturday for the main event. Just as with racing cars, the suspension will be set up stiffer for a dry track, and this will really throw everything out.
Because it has lots of corners, Hockenheim's Club Circuit is a handling rather than power circuit. We have seen a standard-engine 380-hp Porsche GT3 vanquish 600+ hp Porsche GT2s here before.
Unless it rains, all-wheel drive is not necessarily an advantage, like front-wheel drivers, all-wheel-drive cars often understeer too much in the many tight corners. Against the clock on a racetrack, this negates their ability to lay down huge amounts of power effectively on the exit of a bend.
Class 16 Winner:
However, at the end of the day, you have to put circuit lap times in context, and a car that's quick on a racetrack will likely not be super quick on a bumpy public road. In fact, on a wet bumpy public road, it might well be slower than the standard article.
In terms of marques, while BMWs have always figured heavily in the Drift Challenge, the cars have not been represented in the Tuner GP itself since 2006. This is a very strange state of affairs since the M3 can be a very effective track-day tool.
Class 17 Winner:
Maik Freudenstein GmbH & Co. KG
This also means that Porsches tended to dominate the GT Class, vying for overall victory as well. While Ferraris and Lamborghinis have appeared sporadically, they do not seem to be in with a fighting chance here.
Over the years, we've also seen tuners come and go, whether or not they leave a winning mark. Until this year, the big names in Porsche tuning were the top dogs in this event.
From the early years, Gemballa and TechArt went head-to-head each year, swapping victories with almost monotonous regularity. Then in 2006, Uwe Gemballa did not field an entry, stating that the huge amount of orders he had to fulfill meant his workshop could not afford the distraction. Gemballa has never returned.