The Type 46 used a 5.4 L (5359 cc/327 in³) straight-8 engine with 3 valves per cylinder driven by a single overhead camshaft. Power was reported at 140 hp (104 kW).
The engine was undersquare like most Bugatti designs with an 81 mm bore and 130 mm stroke.
The Type 46 was a large car, weighing 2500 lb (1134 kg) and riding on a 138 in (3505 mm) wheelbase. 400 examples were produced from the end of 1929 through 1936.
The three speed gearbox was in unit with the live rear axle, resulting in high unsprung weight, and a relatively harsh ride.
Despite this, the model was a favourite of Le Patron, and it remained in production longer than might have been expected.
A supercharged version, the Type 46S, or Sports model was introduced in 1930. This featured a supercharged version of the 5.3 litre engine. Mated to two Zenith carburettors.
This Roots-type supercharger provided 20 bhp increase in power, but with just 160 hp (119 kW), from its supercharger it was not enough to convince many customers to pay the premium as only around 18 Bugatti Type 46S cars were produced.