The conventional straight-6 engine used an 85 mm (3.3 in) bore and a 115 mm (4.5 in) stroke for a total displacement of 3.9 L (3,900 cc; 240 cu in)[5][8] and a power output of 120 bhp (89 kW) at 4,000 rpm.[1][5][8] The engine power was not suitable for the heavy chassis.[1][2][8]
References
^ abcdef"Lot 244: Bentley 4-Litre/8-Litre Le Mans-style Tourer". Motorbase. Hastings, UK: Classic Vehicles. Retrieved 8 April 2012. A double-drop chassis was adopted, closely based on that of the contemporary Bentley 8-Litre, and offered in two wheelbase lengths: 11' 2" and 11' 8", both of which were shorter than the shortest of the two 8-Litre chassis available.
^ abFeast, Richard (2004). "Chapter 3: Vintage Years". The DNA of Bentley. St. Paul MN USA: MotorBooks International. p. 53. ISBN978-0-7603-1946-8. Retrieved 26 March 2012. ...only 50 4-litres were completed before Bentley Motors was acquired by Rolls-Royce.
^ abc"HISTORY OF MARQUES: BENTLEY - British". Sportscars.TV. 1964. Archived from the original on 6 August 2010. Retrieved 8 April 2012. There was nothing to compalin about in the engine design, but unfortunately the very heavy 8-litre chassis was used and this resulted in a rather dull and slow car.