The beautifully finished and trimmed cockpit of Clarks’ Lotus 25 at Monaco 1963. Leather bound Mota-Lita steering wheel, a dash full of Smiths instruments including its famed chronometric tach and right hand change for the 5 speed ZF ‘box. Naked aluminium of the monocoque chassis below the shift lever. (Yves Debraine)
The tell-tale on Jim Clarks Lotus 25 after his retirement from the 1965 Monaco Grand Prix is at 9500rpm…
He was comfortably in the lead of the race by 14 seconds when the car engaged 2 gears at once on the entry to the Gasometer hairpin. Graham Hill inherited a lead he maintained to the race’ conclusion.
Clark in classical pose. Lotus 25 Climax. (Eric Della Faille)
The Lotus 25, the first ‘modern monocoque’ appeared at the Dutch Grand Prix in 1962 and was much copied for the 1963 season. For ’63 the car remained much unchanged other than small details and power increases from the Coventry Climax FWMV 1.5 litre quad cam, 2 valve V8.
Lucas fuel injection was adopted and a changed bore/stroke ratio allowed higher rpm and power.
Lotus retained the ZF gearbox but also tried a 6 speed Colotti-Francis ‘box and later in the season a Hewland 5 speed transmission which would soon become ubiquitous.
Surtees gesticulating at the fast approaching Ginther. (Marti)
John Surtees and Richie Ginther in Ferrari T56 and BRM P57 respectively scrapped for much of the race, this shot is on the entry to the Gasometer hairpin. Ginther tries to pass with Surtees gesticulating in protest.
Ginther finished second to teammate Hill, with Surtees, sitting in a pool of oil and with falling oil pressure finished fourth and set fastest lap on the last lap and the lap record. McLaren was third in his Cooper T66 Climax.
John Surtees eyes focused on a Monaco apex, Ferrari T56/156. (Yves Debraine)
Ferrari competed with interim cars for much of the season using the V6 engines which won the World Championships in 1961. The 1964 car appeared at Monza powered by a V8, the development of the car in ’63 setting up Surtees’ tight title victory in 1964.
Surtees again, here chasing winner Graham Hill’s BRM P57. (unattributed)
Clark enroute to what seemed a certain victory, before the intervention of gearbox dramas in his lithe, lissom utterly luvverly Lotus 25. (Unattributed)
To the victor, the spoils. Graham Hill ‘The King of Monaco’ after the first of his 5 wins in the Principality. (Getty Images)
Lotus 25 Climax cutaway drawing by James Allington…
This short article makes no attempt to put into perspective one of the most successful and influential racing cars of all time, the first ‘modern monocoque’ includes amongst its relatives all monocoque racing cars built since its debut at Zandvoort in May 1962.
‘Monocoque’ construction by riveted ‘D section’ light alloy longerons attached to fabricated steel bulkheads front and rear.
Front suspension by upper top rocker operating inboard mounted coil spring /damper unit, lower wishbone and adjustable sway bar. Rear suspension by upper top link, inverted lower wishbone and coil spring/damper unit and adjustable sway bars. Cast alloy uprights front and rear.
Girling disc brakes, rack and pinion steering.
Wheelbase 91 inches, track front 51.5 inches, rear 51.75 inches, overall length 146 inches, dry weight 990 pounds. Wheel sizes 5X15 front and 6 or 6.5X15 inches at rear.
Coventry Climax FWMV 1.5 litre 90 degree V8. Bore 67.8mm, stroke 51.6mm, 1496cc, Lucas fuel injection, compression ratio 10.5:1, weight 290lb, 194bhp @ 8500rpm.
ZF gearbox mainly used in 1963 but Colotti and Hewland also tried.
Clark and Chapman with a ’63 spec 25, its essential elements as described above. (Unattributed)
Clarks 1963 Championships…
Jim Clark, Dutch Grand Prix June 1963. Jim zooms his Lotus 25 between the North Sea sand dunes at Zandvoort on his way to victory. (Yves Debraine)
That Jim Clark and the Lotus 25 were the fastest combination in 1962 was not in doubt but Coventry Climax reliability was not as great as BRM’s that year. In 1963 the promise of ’62 was realised with Clark winning five Grands’ Prix and both the Drivers Championship for himself and the first Manufacturers Championship for Lotus.
Clark finished second in a Lotus 29 Ford in his first foray to Indianapolis and further demonstrated his versatility with wins in cars as diverse as the Lotus 23 sports car and Ford Galaxie touring car/saloon that year.
Clark became the standard by which other drivers were judged in 1963, if not earlier.
The cover shot of Clark is at the Dutch Grand Prix, Clark won on the 25’s debut there in 1962 and in 1963 and 1964, all in 25’s and in 1965 in the updated Lotus 33 also Climax FWMV V8 powered.
Oulton Park Gold Cup 1963…
Not only did Jim Clark win the Oulton Park Gold Cup during 1963 but he also recorded some stunning in car footage at the Cheshire circuit in his Lotus 25, such footage very rare at the time.
There were four Non-Championship F1 races in the UK alone in 1963, lucky Brits! The footage is amazing on so many levels not the least of which is a drivers eye period view of the circuit; typical track edges, the lack of run off areas and the topography of trees, ditches and the like for the unwary…and this is a circuit devoid of the ‘special obstacles’ of the ultra dangerous road circuits of the day on which Clark raced. The Nurburgring, Spa, Reims, Pescara and Longford here in Australia spring to mind.
Ok, he is not racing but the precision and accuracy for which he was renowned is also on display…
An ace in every sense of the word.
Etcetera…
Clark tootling thru the Oulton paddock in his ‘camera car’, its a bit hard to pick out the beefy mount against the dark background. And to think in the day of the ‘GoPro’ this was how it was done only a short time ago. Even when the specialists at Channel 7 in Australia popularised in car footage in the ‘Bathurst 1000’ in the late 70’s the heavy rig occupied a good percentage of the rear seat area…progress! (Unattributed)
Photo Credits…
Yves Debraine, Eric Della Faille, Marti, James Allington cutaway drawing, Automobile Year 13, Peter Windsor
Finito…
primotipo... 
[…] https://primotipo.com/2015/03/03/lotus-25-jim-clark-monaco-1963/ […]
[…] Sources / More to Read: John Surtees Official site Wikipedia: John Surtees MBike: Photo Album Primotipo: Lotus 25 – Jim Clark – Monaco 1963… Στα Ελληνικά: ΜotoGP Legends: John […]