AC Schnitzer S5 Silhouette
Longtime readers of ec are likely to remember AC Schnitzer's Silhouette. We reported on this particular car in our April 1992 issue as one of the first complete E34 tuning programs. At the time the car was under the care of Claus Ettensburger from CEC. As the sole U.S. distributor for AC Schnitzer products, Claus wanted to have a showcase for the complete line of AC Schnitzer E34 products. So he sent his personal car to Germany for the Full Monty.

Most noticeable is the Schnitzer Silhouette wide-body kit, consisting of a front spoiler, rear apron, side skirts, rear wing and four fender arches. Schnitzer's Silhouette was styled as an exercise in race-like styling without adversely altering the silhouette of the vehicle. Whereas most Schnitzer body kits are made from PUR Rim, the Silhouette kit is constructed from lightweight fiberglass with Kevlar reinforcement in the rear wing.
1991 Bmw Ac S5 Engine Bay View

The large fender flares enable some serious rubber to be stuffed underneath. Initially the Silhouette was fitted with 3-piece 9 x17s in front and massive 11 x 17s in the rear, but Steve replaced stockers with Schnitzer one-piece forged units. For tiresSteve uses Dunlop SP 8000s (255/40-18 in front and 285/35-18 in the rear). Other items in the package include blackout headlights, mono-windshield wiper conversion, badges and floor mats.

An aggressive stance is provided by Schnitzer's sport suspension, designed to lower the car by about 35mm yet still retain a reasonable comfort level. As there are so many E34 varieties in Europe, Schnitzer offers a kit for every version, including those with self-leveling suspensions. This car has Schnitzer/Bilstein struts and shocks, Schnitzer springs and adjustable anti-roll bars (26mm in front and 19mm in the rear). Since our first road test, the Silhouette's suspension has been unchanged save for the addition of a Racing Dynamics stress bar. Our driver who tested the car at the time remarked, "The large contact surface on the ground, coupled with the massive tires and wheels, provided the kind of performance that I've come to expect from the best two-door sport coupes."

Upon opening the hood, it's hard not to notice the valve cover bearing the AC Schnitzer name or the red 3.7 numbers on the matching airflow sensor cover. This engine is only one of the E34 chassis engines available from Schnitzer at the time. Six-cylinder engines are available with displacements ranging from 2.7L up to 3.7L. It's been said the engine in this particular car measures in even larger at 3.8L, but that was not able to be confirmed at the time of writing. The largest 6-cylinder engine advertised is Schnitzer's S5 3.7L, measuring 3627cc with a 92.5mm bore and 90mm stroke compared to 92mm and 82mm for a standard 535i.

Accomplishing such gains requires replacing many engine components. In this case, Schnitzer replaces the pistons, crankshaft and connecting rods. Modifications are done to the cylinder head, manifolds, block and engine management system. The exhaust tract is freed up with a complete exhaust system, including a header, catalytic converter and mufflers.

Since we last saw Schnitzer's S5 Silhouette, the only detail changes are the addition of window tinting and a Clarion 6-gazillion-watt stereo system. For now, the Silhouette is driven only occasionally as it is once again at CEC awaiting a new home. Steve isn't too keen on selling it, but how many wild 5 Series cars does one need? Particularly since there is an all-new M5 coming around the corner.

With the passing of the E34 chassis, the M5 also passed. Having installed a large V8 engine into the new E39 5 Series chassis, BMW felt there was no need for an M5 model and left it up to the tuning industry to provide the go-fast bits. Currently, the top-of-the-line 5 Series is BMW's 540i. With a manual transmission, the 540i beats the E34 M5 with a 0-to-60-mph time of 5.8 sec..