TheRennmax name was applied to a series ofopen wheel racing cars andsports racing cars constructed by Rennmax Engineering inSydney, Australia between 1962 and 1978.[1] Rennmax Engineering was established by Bob Britton in 1961, its name derived from the 1950s GermanNSU motorcycles Max and Rennmax, with "Renn" meaning race.[1] The1953 and1954 250cc World Championships were won byWerner Haas riding a NSU Rennmax.
Although Rennmax cars are often referred to by model designations such as BN2, BN3 etc., Britton claimed that the origins of these were unknown to him and in practice he did not even stamp chassis numbers on his creations.[2] The following list utilises these unofficial model designations and also includes models which were built by Rennmax Engineering but raced under names other than Rennmax.
The first Rennmax chassis, built for Noel Hall in 1962, utilised numerous components from Hall'sCooper, including a 2.2-litreCoventry Climax engine.[2]
The Rennmax BN1 was a single seater racing car incorporating concepts from theLotus 20 &Lotus 22 designs.[3] At least 6 examples were built circa 1962–1964.[3]
The Rennmax Vee was aFormula Vee racing car produced in series for Greg Cusack and Bruce Burr.[4] Nine cars were built during 1965–66.[1] The cars were originally referred to as CBs but each example was later renamed to "Rennmax".[2]
TheMildren Maserati was asports racing car built forAlec Mildren in 1965.[4] It was constructed in the style of theLotus 23, utilised various components from aCooper T51 and was powered by a 2.9-litreMaserati Type 61 engine.[4]
A series of replicaLotus 23 sports racing cars were constructed[4] in the mid 1960s.[2]
TheMatich SR3 sports racing cars were constructed by Rennmax Engineering forFrank Matich.[2] Bob Britton then accompanied Matich to the United States when he competed in the1967 Can-Am season.[2]
The Rennmax BN2 was a one-off single seater model, based on theBrabham BT14 and built forMax Stewart in February 1968.[5] It used a 1.5-litreFord twin cam engine.[5]
TheMildren, based on theBrabham BT23, was produced forAlec Mildren in 1968.[6] Initially power by a 1.6Alfa Romeo engine, it later used aWaggott powerplant.[6]Racing as the Mildren Waggott, the car was used byMax Stewart to win the1969 Australian Formula 2 Championship, the1970 Australian Formula 2 Championship and the1971 Australian Drivers' Championship.
The Rennmax BN3 was an open wheeler design derived from the Brabham BT23-based Mildren.[6] Five examples were built between 1968 and 1971.[6]
A Rennmax sports racing car, powered by a 2-litre BMW engine, was built in 1970 for Doug Macarthur.[2] A second chassis was built the following year for Ray Hanger who also commissioned another example in 1982.[2] This model has been referred to as the Rennmax BN6[7] although this designation has also been applied to anAustralian Formula 2 car of 1974. (see Rennmax BN6 (Formula 2) below)
The Rennmax Repco was a one offsports racing car built in 1972 for Lionel Ayers and powered by a 5-litreRepco V8 engine.[4]
The Rennmax BN6 was a one off prototype of the BN7Australian Formula 2 car of 1974.[4] The BN6 designation has also been applied to the 1970-71 Rennmax sports racing car. (see Rennmax BN6 (Sports racing car) above).
The Rennmax BN7 was anAustralian Formula 2 car of 1974, four of which were built.[1]
A secondFormula Vee design was released in 1975.[1] Fourteen examples were built.[8]