The story of the 100:

The 100 is the first real Big Healey despite its 4 cylinders.

The mechanical base: Austin A90 transmission engine, standard BMC gearbox for the BN1.

The 100 was built in two variants: the BN1 series, with three speeds was built in 10,688 units and the BN2 series with four speeds, built in 4,604 units.

The BN2 was fitted with a true four-speed manual gearbox, the last two gears always being overdrive. The BN2 differed from the BN1 primarily in larger front wheel arches, a different rear axle and the optional availability of two-tone paint. The year 1955 saw the launch of a high-performance variant, the 100M, which in particular provided the engine with larger carburettors, a new airbox improving the air intake and camshafts with increased lift. The compression ratio of the engine was 8.1:1 and the power output reached 110 hp ( 82). The other modifications made included in particular the stiffening of the front suspension, the installation of an air intake along the bonnet, the addition of leather bonnet straps… About 70% of the 100M received a two-tone paint. A total of 640 copies of 100M were produced. Except for the high compression pistons, all the distinctive mechanical elements of the 100M were also available as retrofit on the BN1 or BN2 thanks to the Le Mans Engine kit; the engine thus reached a power of 100 hp (75) at 4500 rpm. Initially available only in carmine red, the 100M later adopted a more extensive color palette: Reno red, satin green, Healey blue, Florida green, Old English white, silver-grey (about 50 copies). Two-tone paint choices included white-black, Reno red-black, Healey blue-white, black-Reno red, and Florida green-white pairings.