Its history, at a glance
- Built in the first half of 1938.
- Delivered in June 1938 to tyre manufacturer Dunlop.
- Employed for the testing of high-performance tyres for particularly fast and heavy vehicles.
- Adopted into the collection of the Mercedes-Benz Museum during the 1950s.
- 2011: Starting signal given for full restoration to original condition at Mercedes-Benz Classic.
Mercedes-Benz 540 K Streamliner: The vehicle
- Chassis and engine of the Mercedes-Benz 540 K
- Streamlined aluminium body – an absolute one-off.
- Designed strictly in accordance with the understanding of aerodynamics at the time of its creation; flowing lines, low silhouette, minimal surface interruptions; panelled underbody.
- Technical data Cylinders: 8/in-lineDisplacement: 5401 ccOutput: 85 kW (115 hp), with supercharger 132 kW (180 hp)Top speed: 185 km/hDrag coefficient of Cd = 0.36
- The longer transmission ratio identified on the rear axle, at i = 2.90 (rather than i = 3.08, as for the standard-production 540 K models) prevents the engine from overrevving at the higher top speeds made possible by the optimised aerodynamics.
On the trail of evidence
- The chassis frame tells the story: traces of aluminium provide clues about the bodywork, residual colour about the silver paintwork, drill holes about the attachment of the full underbody panelling, indications of wear about the testing programme at Dunlop.
- Thorough research in the archives produced some important findings: following comparison with the entry in the commission book, the numbers found on the frame confirmed the vehicle’s authenticity. Further documents revealed the use of silver-bronze paintwork, grey interior appointments and walnut wood trim.
- An important basis for the restoration was provided by the photos, quotation drawings and – the biggest find of all – a historical description of the surface of the outer shell. This drawing, produced in February 1938, includes certain important details that were found on the original frame.
The restoration and reconstruction
- Time frame: early 2012 to mid-2014 (approx. two and a half years).
- Restoration and reconstruction to the original condition using contemporary craft skills, methods and materials.
- The original line drawing of 1938 was transposed in meticulous detail to a 3D surface model, using sophisticated CAD design techniques, to provide the basis for production drawings, auxiliary tools and templates.
- Extreme precision in the preparation and implementation of every detail and each stage of the work.
- Original components were preserved and re-used – and still show the marks of time.
- Careful craftsmanship was involved at every stage. Rebuilding the body shell alone involved more than 4800 hours of work – the sort of effort and expense that simply cannot be compared with a conventional restoration.
- Reconstruction of the underbody panelling with the help of aerodynamic experts from Mercedes-Benz passenger car development.
- Repair of engine and transmission, and subsequent testing of components, on the output dynamometer of the engine development department in Untertürkheim.