When this 1959 Autobianchi Bianchina rolled out of the factory it was powered by a 15 horsepower straight-twin engine. However ItsBenModified plans to power the car with a motorcycle engine and ride on a custom chassis with narrowed 1993 Miata suspension. In this episode he explains the engine was switched from a Honda CBR600 inline-four to a Yamaha R1 inline-four. This change increases the power from 100 hp to 150 hp.
Source: ItsBenModified