Bugatti - Bugatti Type 40
The Bugatti Type 40 was the 4 cylinder Bugatti model that took over from the Brescia Type 23. Built for 1926, it's engine was basically half of a Type 44, making it a 4 cylinder 1500cc. This was referred to as "Bugattis Bullnose Morris", the least expensive model in the range built for the (relatively few) masses! The same basic engine (with different sump) was used in the GP type frame to make the Type 37 and supercharged 37A. The Type 40 invariably had a Grand sport type body and wire wheels, but for 1930 a few Type 40A were made normally with Roadster type coachwork (and a different gear lever with a knob on it) which had the 3 mm bigger bore block of the Type 49 on it, but not the twin plug arrangement, which brought the capacity up to 1627cc.
Tyre size; The perfect period correct tyre for a T40 is the Blockley 450x19 . Blockley also produces a slightly taller and wider 475x19 tyre but if this is being considered we would suggest it be used on the rear only to gear up on Rallies etc. But the Blockley 450x19 tyre is the perfect choice on an original car, and they are the best tyres available in any case.