BRM 4-cylinder engine

The BRM 4-cylinder engines are a series of four-stroke, naturally-aspirated, 2.5 L (150 cu in), inline-four Formula One racing engines, designed, developed and built by British Racing Motors, between 1956 and 1960. They were exclusively used by BRM; and powered the BRM team cars. It was constructed to conform the FIA engine requirements; necessitating a 2.5 L naturally-aspirated engine displacement formula. The power output for these motors were between 260–285 hp (194–213 kW), and 205 lb⋅ft (278 N⋅m).[1][2]

BRM 255 BRM 258 BRM 259
Overview
Manufacturer	British Racing Motors
Production	1956–1960
Layout
Configuration	L4
Displacement	2.5 L (153 cu in)
Cylinder bore	4.05 in (103 mm)
Piston stroke	2.95 in (75 mm)
Valvetrain	8-valve, DOHC, two-valves per cylinder
Combustion
Fuel system	Carburetor
Fuel type	Gasoline
Oil system	Dry sump
Output
Power output	260–285 hp (194–213 kW)
Torque output	205 lb⋅ft (278 N⋅m)