The Concept Car: AC Schnitzer V8 TOPSTER
The basis is the BMW Z4 3.0i, in which however "no stone is left unturned".
The most striking optical feature is the enclosed bodywork, now 13 cm wider,
in colours orange / cream.
The life-giving organ is the upgraded version of the 4941 cc eight cylinder,
four-valve engine from the M5. In conjunction with our technology partner, Schnitzer
the engineers have equipped the TOPSTER with special intake and exhaust camshafts.
The cylinder heads have also been fine-machined, the compression raised to 11.5
: 1 and the control unit is reprogrammed.
To improve the exhaust gas flow, a high performance exhaust system has been developed.
The power plant has had to be re-positioned and the entire oil circuit had to
be optimised, so it was necessary to modify the oil sump and oil pump. Finally,
the air flow was improved. By means of new intake pipes and 2 air filter boxes,
the entire intake tract could be optimised. These modifications have together
resulted in the following performance figures: Power: 331 kW / 450 HP, Max. torque:
520 Nm, 0 - 100 km/h: 4.5 seconds, Top speed: 305 km/h.
Furthermore the rear axle (ratio of 3.62:1) has a variable differential lock
from 0-100 % depending on the load of the V8 TOPSTER.
Perfect retardation is provided by the brake kit. This uses brake disks of Ø
365x32 mm at the front and Ø 328x20 mm at the rear in conjunction with
special brake calipers. Even after several "hard brakings", the system
achieves deceleration values of 1 g and more.
In the TOPSTER the driving dynamics are improved by the 9-position adjustable
The V8 TOPSTER keeps contact with the asphalt through the racing rims Type IV.
With sizes 9.0Jx20" offset 18 with tyres 255/30 R 20 (front) and 11.0Jx20"
offset 0 with tyres 305/25 R 20 (rear), the TOPSTER can corner at speeds otherwise
reserved for a thoroughbred Touring Car.
The reshaped bonnet with its unmissable power bulge and air outlet, already
guarantees maximum cooling air flow. Also a new development is the front skirt
which improves downforce. Its large air inlet with integral grille ensures additional
cooling for the engine and front brakes. Consequently the side skirts house
air ducts for the rear brakes. The monstrous rear skirt accommodates not only
an underfloor wing, but also the exhaust system. The specially developed roof
further reinforces the body of the V8 TOPSTER and develops a new body side line
- similar to a coupé. The integral rear roof wing in conjunction with
the two-piece rear wing improves the downforce of the entire body.
The interior of the V8 TOPSTER is a combination of developments in the range
available for many BMW models, and special one-off products. These include the
racing bucket seats as well as the airbag sports steering wheel, gear lever
gaiter and handbrake cover which are made in Alcantara with orange stitching.
A carbon-fibre interior and chromed cover for the standard roll-over bar and
the aluminium accessories are however components of the standard range for the
The AC Schnitzer V8 TOPSTER was developed as a technology showcase. In the equipment
level and form shown here, this concept car would cost around € 185,000.00.
Series production is not planned.