Top speed records are worth their weight in gold in tuner car circles where bragging is expected and actually being able to back up these claims is less often the norm. The German modification house AC Schnitzer->ke312 has just attained one of those coveted titles just the other day with a customized BMW 335d. Yes that's right, d stands for diesel, making the alternatively fueled ACS3 Series->ke290 the fastest street legal diesel in the world. The location for the record setting event was the infamous Nardo test ring in Italy, a 7.8 long circle with just enough banking to let the driver keep the wheel as straight as possible at over 200 MPH on a closed course.

In this case it was the editors of AUTO BILD who piloted the Continental tire shod AC Schnitzer modified BMW 335d, a car that gets 36 MPG on the highway from the factory along with the fun of a 265 HP twin turbocharged inline six cylinder engine to a top speed of 288.7 km/h, or 179.3 MPH in American. The 335d used the German tuners simple and straightforward performance packages that boost torque to a whopping 405 lb-ft and drops the diesel powered sports coupe’s 0 to 60 MPH time by a full half second taking it down to a very sporty 6.1 seconds.The power mods consist of a reprogrammed computer module to increase turbo pressure and add a bit more fuel to the mix while a stylish twin tip exhaust pokes out from either side of the rear bumper and give the green BMW a more aggressive groan. Although 180 MPH may not sound that impressive along side 250 MPH machines like the Bugatti Veyron and Ultima SSC, it is reassuring to see that there is an interest in diesel performance. Now if only Audi would produce the R8 TDI super car this record would easily be theirs without any help from the aftermarket.

Video and press release after the jump.

Press release

It's a hat-trick: for the third time, AC Schnitzer has gone to Nardò in southern Italy and brought home a third world record for Aachen.

The legendary high-speed circuit has already been the setting for so many records. Once a year in southern Italy, under the aegis of “CONTINENTAL AG” and in collaboration with the editors of “AUTO BILD sportscars”, the 'creme de la crème' of vehicle tuners go head to head - this year on 18th and 19th October 2009.

The AC Schnitzer ACS3 3.5d Coupé succeeded in breaking the world record from 2006 for the fastest road-legal diesel car by over 8.7 km/h.

288.7 km/h was the figure on the display of the GPS speedometer system on the 13 km long high-speed circuit - which is in principle a giant oversized circle - after the fast lap of the AC Schnitzer ACS3 3.5d Coupé.

After the records from 2006 with the TENSION as the fastest road-legal BMW, the world record still held by the GP3.10 GAS POWERED from 2007 for gas-powered vehicles, the ACS3 3.5d Coupé (based on the BMW 335d) has continued the success story.

Naturally the power upgrade which took the latest world record holder to success is part of the extensive AC Schnitzer special accessory range and available for all vehicles based on the 3.5d engine. It is TÜV-approved and available from BMW dealers.

Another impressive performance in Nardò came from the AC Schnitzer ACS4 3.5 turbo (based on the BMW Z4 sdrive 35i). At 303.1 km/h, this was not a new world, but such a high speed is almost unheard of for a Roadster. The Z4 was also running with the commercial version of the AC Schnitzer performance upgrade for 3.5i engines.