Elfin Type 100 Mono
{{Use dmy dates|date=November 2019}}
{{Infobox automobile
| image = 1965 Elfin Mono.jpg
| name = Elfin Type 100 Mono
| manufacturer = Elfin Sports Cars
| production = 1964-1969; 19 builthttp://melbourneclassics.com/files/ELFIN_MONO_LIST2.pdf {{Bare URL PDF|date=March 2022}}
| predecessor = Formula Junior / Catalinahttp://www.shannons.com.au/library/events/ELFIN.PDF {{Bare URL PDF|date=March 2022}}
| successor = Elfin 600John Blanden and Barry Catford, Australia's Elfin sports and racing cars, 1997, Page 80
| class = Australian 1½ Litre Formula
| platform =
| body style =
| engine = Lotus Twin Cam
Clisby V6
Ford 1500
Ford Cosworth 1100
| length =
| width =
| height =
| weight =
| related =
| designer = Garrie Cooper
}}
The Elfin Type 100 Mono is an Australian 1½ Litre Formula racing car produced from 1964-1969 by Elfin Sports Cars. The name "Mono" refers to the fact that it was constructed upon a monocoque design.
Development
File:Elfin Mono Type 100.jpg]]
In 1963, Garrie Cooper began work on a revolutionary monocoque design of a car intended to dominate the newly created Australian 1½ Litre capacity class. Lotus Cars had already built the Formula 1 monocoque under the direction of Colin Chapman but the idea was still in its infancy so Cooper had only vague ideas of the design. The monocoque build removed the need for the traditional "Superleggera" tube frame chassis and harnessed a very light sheet steel frame to which aluminum panels were riveted for a very stiff structure. The finished structure weighed approximately 80 kg less than the tube framed Elfin Catalina it replaced. Uniquely, the hollow section of the body was sealed off to serve as the petrol tank. The Elfin Mono eventually made its debut at the August 1964 Melbourne Racing Car show and orders quickly followed.http://melbourneclassics.com/files/THREE_AUSTRALIAN_GPs.pdf {{Webarchive|url=https://web.archive.org/web/20160303200944/http://melbourneclassics.com/files/THREE_AUSTRALIAN_GPs.pdf |date=3 March 2016 }} {{Bare URL PDF|date=March 2022}}