Legacy Metrics

1951 Bentley Mark VI Drophead Coupé (Mulliners of Birmingham coachwork, one-off design)

B342NZroadUnited Kingdom
Engine
4.5L F-head inline-six with full-flow oil filter and dual exhaust
Colour
Three-tone grey

Bentley Mark VI chassis B342NZ is a unique one-off drophead coupé bodied by Mulliners of Birmingham to a bespoke design by Stuart Peck, one of only five such bespoke open bodies on the entire Mark VI production run. Commissioned by Sir John Black, Managing Director of Standard Motor Cars, the car passed through several American owners before a comprehensive five-year, 12,000-man-hour restoration was undertaken in California. It subsequently earned class and show honours at the Pebble Beach Concours d'Elegance and other major California concours events.

Ownership

  1. Auction sale
  2. 1973 →Acquisition unknown
    Dr. Kurt Hammerstrom
    partial documentation

    Initiated a restoration but then placed the car in long-term storage for roughly 37 years; the car passed to the next owner through his estate.

  3. Date unknownFactory delivery
    Sir John Black
    partial documentation

    Managing Director of Standard Motor Cars, he commissioned the bespoke coachwork to a one-off Mulliners design; reasons for ordering the car remain unclear, with theories involving the coronation and Triumph design study.

  4. Date unknownPrivate sale
    Leslie Onslow
    partial documentation

    Resident of Bournemouth; acquired the car roughly two months after Triumph's post-war sports cars were launched, suggesting Sir John had fulfilled his purpose for the Bentley.

  5. Date unknownAcquisition unknown
    C.J. Gelber
    partial documentation

    California-based owner who used the car regularly for approximately a decade after it moved to the United States.

  6. Date unknownAcquisition unknown
    A. Sheratin Atkinson
    partial documentation

    California-based owner; succeeded Gelber in the chain of custody.

  7. Date unknownAcquisition unknown
    California Rolls-Royce and Bentley collector
    partial documentation

    Long-standing member of RROC, RREC, and Bentley Drivers Club; commissioned a comprehensive mechanical and cosmetic restoration lasting five years and over 12,000 hours, then showed the car extensively in California concours events.

Competition

  1. 2014
    2014 Pebble Beach Concours d'Elegance

    Displayed in the post-war Touring class; no award result mentioned for this specific event.

  2. Ironstone Concours
    Best in Class and Most Elegant Open Car

    One of several California concours appearances following the Pebble Beach showing.

  3. Niello Concours
    Best in Class and Best of Show

    One of several California concours appearances following the Pebble Beach showing.

  4. Hillsborough Concours
    Best in Class

    One of several California concours appearances following the Pebble Beach showing.

Maintenance & restoration

  1. 1973
    Restoration

    Dr. Hammerstrom initiated a restoration after acquiring the car but did not complete it; the car was subsequently placed in storage for roughly 37 years.

    The extent of work completed before storage is unspecified.

  2. Restoration
    Bentley specialists (unnamed)

    A comprehensive five-year mechanical and cosmetic restoration carried out by Bentley specialists to an authentic standard, involving over 12,000 man-hours. The original black exterior was replaced with a three-tone grey scheme; red leather interior is piped in grey; polished crotch-burl veneer with fiddleback pattern fitted throughout. The factory Radiomobile 100 radio was converted to AM/FM with concealed door speakers, while the original clock was retained.

    Commissioned by the California-based enthusiast who acquired the car from the Hammerstrom estate; concluded prior to the 2014 Pebble Beach appearance.

Are you the owner of this car?

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Each chassis record is compiled from public auction archives and links to its source material. Ownership, competition and maintenance entries are extracted from those catalogue listings by an LLM, which can make mistakes — please contact us with any corrections. The summary is Legacy Metrics’ own writing; we do not reproduce catalogue text.

“Full” and “partial” documentation labels indicate how well each entry is corroborated in the underlying sources, not an audit of the car’s physical paperwork. Names of recent or living owners are withheld for privacy.