1961 Lotus 18

The Lotus 18 was the first mid-engined vehicle built by Lotus. The design was created by Colin Chapman, the founder of Lotus, specifically for Formula 1 and Formula 2 racing. The mid-engined design brought the Lotus racing efforts to another level and greatly improved their ability to compete in the fiercely competitive formula series.

The lightweight, powerful, and simple design was the correct combination and the car proved to be rather competitive. It was powered by a 2.5 liter Coventry Climax engine but after rule changes occurred in 1961, the displacement was reduced to 1.5 liters. The chassis was constructed from a space-frame unit and lightweight body panels were bolted on, creating a lightweight, rigid, and strong design.

The first Formula One victory for the Lotus 18 came from a privateer named Rob Walker. This was the start of many podium finishes and a career that would last a rather long time in terms of racing. Lotus introduced the 21 and 24 but it was not until the Lotus 25 did Lotus find a suitable replacement. The Lotus 25 featured a fully stressed monocoque chassis which was the first of its type to be used in Formula One competition. This made the car more rigid and stronger than other cars in F1.

In the United States, the Lotus 18 dominated the Formula Junior series. Arundel, Clark, and Stacy won nearly all the events that they entered. In Formula Junior specification, the cars were powered by a 1100cc Ford Cosworth engine that produced around 100 horsepower. The brakes are aluminum finned drums and the suspension is comprised of wishbones.

Two Lotus 18 Formula Junior cars were later converted to Formula One specifications. The Lotus 20 and 21 were the successor models to the Lotus 18. The 21 was used in Formula One while the 20 was the Formula Junior entry. Some 18 chassis were rebodied with 21 skins to create the interim Lotus 18/21 hybrid derivative. 27 examples were built by Lotus. 18 were built in 1960 and 9 in 1960.

By Daniel Vaughan | May 2012