Follow Motorbase:
Search Motorbase for

Lot 678: 1959-60-type BRM P25 2˝-litre 4-cylinder Formula 1 Racing Engine
Coachwork by Hall & Hall

Collectors' Motor Cars and Motorcycles, Bonhams (3 December 2007)

This magnificent piece of late 1950s Formula 1 engineering design is the spare power unit for the 1959 Dutch Grand Prix-winning BRM Type 25 offered in Lot XX. This power unit was manufactured new in the past six years by celebrated marque specialists Hall & Hall Ltd of Folkingham and Bourne, Lincolnshire, for the car’s contemporary owner, the late Spencer Flack.

BRM’s founding Chief Engineer Peter Berthon opted for the simplicity of an in-line 4-cylinder twin overhead camshaft racing engine in 1953-54 after the continual trials and tribulations he had experienced in attempting to develop the original 1˝-litre centrifugally-supercharged BRM Project 15 V16-cylinder engine, 1949-53. The original design of this new engine for the forthcoming 2˝-litre Formula 1 category had actually been conceived by consultant engineer Stuart Tresilian. He had offered the idea to HWM and Connaught before it was taken up by BRM, and it was Peter Berthon who then opted for a two-valve per cylinder head design instead of Tresilian’s alternative four-valve per cylinder concept.

The first BRM Type 25 car powered by one of these engines emerged late in 1955 and was given its racing debut in the Oulton Park Gold Cup that September, driven by Peter Collins. He retired after showing strongly when the oil pressure gauge zeroed. Post-race inspection proved that the needle had merely been shaken off its spindle by the lusty new engine’s vibration! Such was BRM’s luck at the time…

Through 1956 the latest semi-monocoque chassised 4-cylinder BRM Type 25s were campaigned by Mike Hawthorn and Tony Brooks. They proved very fast but fragile, and led the British GP at Silverstone, running rapidly first and second ahead of Ferrari, Maserati, Vanwall etc. In 1957 the cars were progressively developed and in 1958 withy new detachable-body spaceframe chassis in the latest Type 25 cars, Jean Behra drove a BRM to its first International Formula 1 race win in the non-Championship Caen GP. He and Harry Schell also finished 2-3 in the Dutch GP. Joakim Bonnier later won the 1959 Dutch GP in car ‘258’ – now offered in Lot XX here – to score BRM’s maiden World Championship-qualifying Grand Prix win, after 11 years of trying.

The BRM P25 racing engine began life with four main bearings, was later modified to five, and this particular Hall & Hall-built unit has the five-bearing crankshaft, adding useful extra expected life and minimising vibration from the powerful 4-cylinder unit. On the Hall & Hall test bed at Folkingham – in the BRM team’s 1959 test house – we are advised that this engine has returned over 270-horsepower. This is therefore a most attractive spare power unit for any Type 25 owner while – with suitable modification – it would also be suitable for rear engined installation in surviving BRM P48 Formula 1 chassis.

Lot Details
Auction Collectors' Motor Cars and Motorcycles
Bonhams, Olympia, London,
Lot Number678
Outcome NOT SOLD
Hammer Price-
Hammer Price (inc premium)-
Condition rating
Registration number
Chassis number
Engine number
Engine capacity (cc)
Engine - cylinders
Number of doors