Lotus 18

Infobox Automobile


name = Lotus 18
manufacturer = Team Lotus
production = 1960
predecessor =
successor =
class = Formula One, Formula Two, Formula Junior
body_style = Open wheel
engine = 2.5/1.5 Litre Coventry Climax, 998 cc Ford CosworthThe Lotus 18 is a race car designed by Colin Chapman for use by Lotus in Formula Junior, Formula Two, and Formula One. It was the first mid-engined car built by Lotus, and a marked improvement over Chapman's early and only moderately successful front-engined formula cars, the 12 and 16. It was introduced for the 1960 F1, F2 and FJ seasons. As a stop-gap before the introduction of the 18's successor models, the Lotus 20 and 21, some 18 chassis were rebodied with 21 skins to create the interim Lotus 18/21 hybrid derivative.

Design

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 [Setright, L.J.K., "Lotus: The Golden Mean", in Northey, Tom, ed. "World of Automobiles" (London: Orbis, 1974), Volume 11, p.1228.] (almost spaceframe) chassis. Thus the car was rigid and strong.

It was powered initially by a 2.5 litre Coventry Climax four cylinder engine, inherited from the 16, [Setright, p.1228.] which produced 239 hp (178 kW) from a weight of only 290 pd (132 kg), [Setright, p.1228.] and had a wide torque range. [Setright, p.1228.] Chapman, to capitalize on this, designed a light, sleek machine, only 28 inches (71cm) high (except for windscreen, and weighing just 980pd (440 kg). [This was virtually the same as the 16 with, oddly enough, more weight actually on the front wheels. Setright, p.1228.] To help facilitate this, the driver was placed in a semi-reclining position, [Setright, p.1228.] pioneered about a decade before by Gustav Baumm of NSU. [Setright, p.1230.]

Race performance

Chapman gave the 18 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 car Grand Prix racing had ever seen, [Setright, p.1229.] eclipsing even the legendary Auto Unions, and being widely copied (as well as built as a two-seat sports-racer, the 19 or Monte Carlo). [Setright, p.1228.]

The car took Lotus' first F1 victory, albeit by privateer Rob Walker, who leased the car from Chapman. Driven by Stirling Moss, the car took a dominant win at the 1960 Monaco Grand Prix. It was an early taste of things to come. Moss also won the American Grand Prix at the end of the season, helping Lotus finish third in the constructors' championship. Moss repeated his win in a legendary race at Monaco the following year, beating off the more powerful and faster 'sharknose' Ferraris, and then won at the fearsome Nürburgring in changeable weather, while Innes Ireland took a third win in the USA to help Lotus finish second in the constructors' championship that year. The car was notable for giving Jim Clark his first Grand Prix start in 1960.

The 2.5 litre was replaced by a 1.5 litre Climax with new Formula One engine rules in 1961, and a Formula Junior variant used a 998 cc Ford MAE. The Formula Junior version also used smaller gauge chassis tubing and also used Alfin drum brakes on all four corners, as it did not have to cope with so much power.

The 18 was replaced by the Lotus 21 in Formula One, and the Lotus 20 in Formula Junior in 1961.

Notes