Text & Photos edited by Clinton Deacon
Source: KOHL automobile GmbH
edited 09-19-2006


Tension rises for the 6-series from 630i to M6: The AC Schnitzer TENSION Street Version

The IAA 2005 saw the much-observed premiere of the Concept Car AC Schnitzer TENSION based on BMW M6. The positive reception together with huge demand for this unique vehicle persuaded us to include in our range a road-going version, limited to 50 examples, for conversion from the 630i - M6 model. After just 11 months of development and testing, we now present: the AC Schnitzer TENSION Street Version

Naturally the "small brother" could not be a 1 : 1 copy of the Concept Car, as the TENSION is a technology showcase which demonstrates what is technically feasible. In contrast, the TENSION Street Version had to incorporate suitability for everyday use with no loss of driving pleasure or reliability.

The focal point of the development work was adaptation of the breathtaking, costly aerodynamic conversion for series production.

The bonnet of the AC Schnitzer TENSION, restyled from the standard 6-series, is used on the Street Version. It reveals at first glance, from its large air outlet edged in a chrome frame, that the ventilation of the power plant is actively supported by sufficient cooling air flow. The front skirt of the TENSION technology showcase has been completely adapted. It makes the TENSION Street Version look much lower and at the same time improves downforce on the front axle at high speeds. The air intake provides additional cooling for the engine and the front brakes and also gives the TENSION Street Version its unmistakeable facial expression.

To provide sufficient ventilation for the power plant, the new front wing has integral air outlet openings which with their three chrome ribs and the indicators are reminiscent of a shark's mouth.

Adequate air exchange is essential not only in the front of the vehicle in order to develop its full potential. The same principle applies to the rear.

Consequently, in the TENSION Street Version too air ducts for the rear brakes have been worked into the striking side skirts. The side skirts which give the vehicle its elongated appearance form the smooth transition to the rear, which on the TENSION Street Version in comparison with the Concept Car is still very sporting but slightly less lavish.

The rear skirt houses not just the solid stainless steel twin exhaust system with chromed Sports Trim tailpipes but also a carbon diffuser.

Another highlight at the rear of the TENSION Street Version is the boot lid which was originally reserved for the TENSION. But its modified styling gives the rear of the BMW 6-series the "Finishing Touch", so the new boot lid is now a firm part of the Street Version conversion.

The bodystyling of the TENSION Street Version is completed by the AC Schnitzer sports mirrors and the extravagant two-colour paintwork in Alpine White in combination with Anthracite Metallic. Naturally other paint options are available on request.

What does a costly aerodynamic conversion look like without the right wheel and tyre combination? We think it's incomplete. So we decided to equip the TENSION Street Version with the latest AC Schnitzer wheel generation: the forged alloy Type V.

Appearance is one thing, but much more important in this context is the safety aspect. To take this into account, and secondly to meet the high technical demands placed on the AC Schnitzer wheel by our engineers, a complete new wheel development was required.

The result is the Type V alloy forged wheel with bi-colour finish. It has a partly polished, partly painted surface. This wheel type, available for all 5 and 6-series, achieves a fundamental paradox: reduction in weight with simultaneously maximum wheel diameter and width.

The TENSION Street Version is fitted with rims size 9.0J x 20" on the front and 10.0J x 20" on the rear, and each front wheel weighs in at just approx. 10.8 kg. The tyres to fit the wheels are size 245/35 ZR 20 on the front and 285/30 ZR 20 on the rear.

In conjunction with the wheel and tyre combination, a sports suspension has been developed for the TENSION Street Version which lowers the vehicle by around 25 - 30 mm and perceptibly improves driving dynamics. For the M6, a suspension spring kit is available.

To counter lateral roll, AC Schnitzer antiroll bar sets are fitted to the front and rear axles. Another suspension highlight is our in-house spring strut brace of aluminium which superbly prevents distortion in the vehicle front.

Depending on base vehicle, the TENSION Street Version can be fitted optionally with the new AC Schnitzer 5.1 l engine. This is available in principle for all BMW 6-series with N62 B44 or N62 B48 TU engines.

The new engine offers a true alternative to the M5 or M6. As this conversion is also available for vehicles with automatic transmission, fans of automatics can now enjoy the higher power in conjunction with the pleasures of an automatic.

Whereas the basic engine gives maximum torques of 450 or 490 Nm, the AC Schnitzer 5.1 l engine achieves 550 Nm. Naturally the performance has been optimised. It rises from 245 kW (333 HP) or 270 kW (367 HP) to a superb 302 kW (411 HP). At the same time, driving performance is enhanced. The top speed rises on average by around 35 km/h.

These excellent figures are obtained by the use of specially developed engine components. Individually, these are:

AC Schnitzer special cylinder block AC Schnitzer special pistons

AC Schnitzer special crankshaft AC Schnitzer special catalyst

AC Schnitzer sports rear silencer with chromed Sports Trim tailpipes

AC Schnitzer special cylinder head AC Schnitzer special conrods AC Schnitzer exhaust manifold

AC Schnitzer Control Unit Program

To achieve excellent deceleration figures, the AC Schnitzer high performance brake system from the TENSION has been modified. At the front axle, an 8-pot fixed caliper with perforated, vented brake discs and special pads ensures braking with ruthless efficiency. However, this kit is reserved for the Street Versions based on BMW M6.

Only the interior remains, and this too has been modified in typical AC Schnitzer fashion: Starting with the carbon interior trim in titanium via the 3-spoke airbag sports steering wheel in leather with carbon applications, the automatic selector lever in carbon, the new combi*instrument with a speed display up to 320 or 330 km/h, through to velours mats for footwell and boot with red embroidered logo: this all gives the characteristic look to the interior of the TENSION Street Version. The overall impression is completed with silver or black anodized aluminium accessories comprising pedal set, foot rests, handbrake handle and cover for the controller of the "i-Drive" systems.

Last but not least, the silver serial number on the black anodized aluminium placard on the centre console permanently reminds the driver that he is sitting in a very special car: e.g. TENSION Street Version no. 1/50.

The AC Schnitzer TENSION Street Version is available in various levels. The conversion work is performed exclusively by AC Schnitzer in Aachen. The only exceptions are the USA and Japan, where trained specialists perform the vehicle conversion locally.