Lotus 18
Category | Formula One,Formula Two,Formula Junior | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Constructor | Team Lotus | ||||||||||
Designer(s) | Colin Chapman | ||||||||||
Predecessor | 16 | ||||||||||
Successor | 21 | ||||||||||
Technical specifications | |||||||||||
Chassis | Steelspaceframe | ||||||||||
Suspension (front) | Double wishbone,with inboardcoiloverspring/damper units. | ||||||||||
Suspension (rear) | Lower wishbone, top link, and radius rod suspension, with outboardcoiloverspring/damper units. | ||||||||||
Engine | Coventry ClimaxFPF2467 cc / 2497 cc / 1499.8 ccmid-mounted | ||||||||||
Transmission | Lotus (Ansdale-Mundy) 5-speedsequential manual | ||||||||||
Tyres | Dunlop | ||||||||||
Competition history | |||||||||||
Notable entrants | Team Lotus Rob Walker Racing Team UDT-Laystall Racing Team Equipe Nationale Belge | ||||||||||
Notable drivers | Innes Ireland Stirling Moss Alan Stacey John Surtees Jim Clark Trevor Taylor | ||||||||||
Debut | 1960 Argentine Grand Prix | ||||||||||
| |||||||||||
Constructors' Championships | 0 | ||||||||||
Drivers' Championships | 0 | ||||||||||
n.b. Unless otherwise stated, all data refer to Formula One World Championship Grands Prix only. |
TheLotus 18was arace cardesigned byColin Chapmanfor use byLotusinFormula Junior,Formula Two,andFormula One.
Overview
[edit]Lotus 18 was the firstmid-enginedcar built by Lotus and was a marked improvement over Chapman's early and only moderately successful front-engined formula cars, the12and16.It was introduced for the 1960 F1, F2 and FJ seasons, with about 27 examples of the F1 and F2 versions and 110 of the FJ versions. As a stop-gap before the introduction of the 18's successor models, theLotus 20for F2/FJ and21for F1, some 18 chassis were rebodied with 21 skins to create the interimLotus 18/21hybrid derivative.
The 18 was replaced by theLotus 21in Formula One and theLotus 20in Formula Junior in 1961.
Design
[edit]The car was a classic Chapman design, being extremely light and simple; the body was made up of lightweight panels bolted to heavily-triangulated tube frame[1](spaceframe) chassis. Thus the car was rigid, strong and light, maintaining the 16's forward weight distribution despite the engine moving behind the driver.
It was powered initially by a 2,467 ccCoventry Climax FPF(3.70 "x 3.50" ) four cylinderDOHCengine inherited from theGrand Prixversion of Lotus 16.[2]In 1960, the FPF was enlarged slightly to 2497 cc (3.70 "x 90 mm), which produced 239 hp (178 kW) at 6,750 rpm from a weight of only 290 lbs (132 kg)[2]and had a wide torque range.[2]
The 2.5 litre engine was replaced by a 1.5 Litre (82 mm x 71 mm) Climax FPF Mk.II with newFormula Oneengine rules in 1961. TheFormula Juniorvariant used a 998 ccCosworth Mk.IIIor a Downton BMC "A" Series with 948cc displacement. The Formula Junior version also used smaller gauge chassis tubing and Alfin drum brakes on all four corners.
Further contributing to the weight advantage was the adoption of lightweightsequential manual transmissionoriginally developed forLotus 12byRichard AnsdaleandHarry Mundyincorporating the uniquesequential-shiftingmotorcycle gearbox,and a ZF limited-slip differential in a common Magnesium alloy housing to form atransaxle,which also provided the mounting points for inboard rear brakes. This gearbox had been improved in its reliability forLotus 15and16in 1957-58 byKeith Duckworth,who had just joined Lotus as a gearbox engineer.
AlthoughPorschein Austria pioneered thesequential-shifting gearboxforracing cars,with theType 360Cisitalia,the idea was relatively new and the originaltransaxlein theLotus 12,which was essentially an enlargedmotorcycle gearbox,combined withZFlimited-slip differential, had gained the nickname "Queerbox", or "Gearbox-full of neutrals" for its poor reliability. WithDuckworthhaving left to formCosworthin 1958,Mike Costin,who, despite being the co-founder ofCosworth,remained with Lotus for a while longer, adopted the improvedQueerboxin theLotus 16,into a configuration for directly mounting it behind the engine forLotus 18with dedicated oil scavenge and pressure feed pumps, further improving its reliability while retaining the small and light design.
TheFormula Juniorversion utilized the Renault 4-speed transaxle, and both of the Lotus transaxle and this Renault 'box had the gear shifter lever on the left side of the driver. An optional gearbox was the VW gearbox withHewland4 speed gears. This last gearbox has the added advantage of being able to change gear ratios from behind the gearbox without removing the gearbox from the car.
The front suspension was by double-wishbone arms with an outboard coil/damper unit. Unlike Chapman's former designs where the ends of the anti-roll bar acted as a leg of the upper wishbone, the18had a separate front anti-roll bar. The rear suspension was by upper and lower radius arms with a reversed lower wishbone, where the fixed-length half-shaft acted as the upper-link. The coil/damper unit was also mounted outboard in the rear, and the18sometimes ran with and without the rear anti-roll bar.
In order to capitalize on the weight advantage, Chapman designed a light, sleek machine only 28 inches (71 cm) high (excludingwindscreen) and weighing just 980 lbs (440 kg).[3]To help facilitate this, the driver was placed in a semi-reclining position,[2]pioneered about a decade before byGustav BaummofNSU.[4]
Racing history
[edit]The Lotus 18 had remarkably good handling with a unique suspension system which drastically reduced weight transfer and body roll in cornering. Shortly, the Lotus 18 was proving to be faster than any carGrand Prixracing had ever seen,[5]eclipsing even the legendaryAuto Unionsand being widely copied. It was also built as a two-seat sports-racer called theLotus 19or Monte Carlo.[2]
The car took Lotus' first F1 victory, byInnes Irelandin the non-championshipGlover Trophy,on 8 April 1960.[6]Its first World Championship win happened six weeks later, on 29 May, albeit byprivateerRob Walker,who leased the car from Chapman. Driven byStirling Mossthe car took a dominant win at the1960 Monaco Grand Prix.It was an early taste of things to come. Moss also won theUnited States Grand Prixat the end of the season helping Lotus finish second in the constructors' championship.
Moss repeated his win in a legendaryrace at Monaco the following year,beating off the more powerful and faster 'sharknose'Ferraris.He then won at the fearsomeNürburgringin changeable weather, whileInnes Irelandtook a third win in the USA to help Lotus finish second in the constructors' championship in1961.The Lotus 18 was also notable for givingJim Clarkhis first Grand Prix start in 1960.
The Belgian Grand Prix at Spa in 1960 was notable for Moss's accident in the Rob Walker 18 in practice which kept him from the race and the death ofAlan Staceywhen he left the track in his 18 apparently following a bird strike in the face.
Complete Formula One results
[edit]Championship results
[edit](key) (Results in bold indicate pole position; results in italics indicate fastest lap.)
* Includes points scored by other Lotus models
Non-Championship results
[edit](key)
References
[edit]- Lotus Formula Juniors 1960-1963 - Robinshaw & Bouckley
- ^Setright, L.J.K., "Lotus: The Golden Mean", in Northey, Tom, ed.World of Automobiles(London: Orbis, 1974), Volume 11, p.1228.
- ^abcdeSetright, p.1228
- ^This was virtually the same as the 16 with, oddly enough, more weight actually on the front wheels. Setright, p.1228.
- ^Setright, p.1230.
- ^Setright, p.1229.
- ^http://www.statsf1.com/saisons/gphc/gp.aspx?idGp=169&LG=1[permanent dead link]