In late 1927, Bentley enlarged their 3 Litre model to 4.5 litres and it subsequently dominated endurance racing. Financier and racing driver Woolf Barnato piloted a 4½ Litre to victory at the 1928 24 Hours of Le Mans with co-driver Bernard Rubin.

The 4½ Litre was one of the most successful cars designed by W.O. Bentley and largely produced with the financial support of Woolf Barnato.

Bentley produced the 4½ Litre as a bare chassis, with hood radiator and scuttle to be bodied by an independent coachbuilder. Most were sent to Vanden Plas or Gurney Nutting. Many have since lost their original bodies to replica Vanden Plas Le Mans Tourer-style bodies.

type	Limited Production Car
built at	Cricklewood, Middlesex , England
predeccesor	1921 Bentley 3 Litre
engine	Inline 4
position	Front, Longitudinal
aspiration	Natural
valvetrain	SOHC, 4 Valves per Cyl
fuel feed	2 SU HVG5 Carburettors
displacement	4398 cc / 268.38 in³
bore	100 mm / 3.94 in
stroke	140 mm / 5.51 in
power	82.0 kw / 110 bhp
specific output	25.01 bhp per litre
body / frame	Coachbuilt Body on Steel Frame
driven wheels	RWD
front brakes	Drums
rear brakes	Drums
f suspension	Solid Axle w/Leaf Springs
r suspension	Live Axle w/Leaf Springs
wheelbase	3200 mm / 126 in
transmission	4-Speed Manual