Locost

[
Toyota Corolla GTS Twincam, uprights from a Hyundai Stellar and steering rack from MG MGB.]

A Locost is a home-built clone of the Lotus Seven. The car features a space frame chassis usually welded together from mild steel 1x1" (25x25 mm) square tubing. Front suspension is usually double wishbone with coil overs. The rear is traditionally live axle, but has many variants including independent rear suspension or De Dion tube. Body panels are usually fiberglass nose and wings and aluminium side panels. Each car is highly individualized according to the resources, needs and desires of each respective builder.

The original design was intended to be built from scratch. However, the design has become so popular that several fabricators have begun producing the chassis in kit car form. Additionally, fiberglass body components, suspension pieces and other Locost-specific components can be sourced from various suppliers.

Ron Champion's Locost

The Locost pattern originated with the publishing of the book "Build your own sports car for as little as £250" by Ron Champion (ISBN 1-85960-636-9). This design was based heavily on the original Lotus Seven, with a live axle rear suspension replacing the Lotus's De Dion tube setup.Fact|date=February 2008

Both Colin Chapman and Ron Champion have a background in the 750 Motor Club and the design of the Locost is based on a Clubman's Race Car designed and built by Ron Champion in 1963. The rear is of course "inspired by" Lotus 7.

Haynes Roadster

Ron Champion's original book was followed up with "Build Your Own Sports Car: On a Budget" (ISBN 1-84425-391-0) by Chris Gibbs. The subject car differs most significantly from the original in that it has an independent rear suspension. Additionally, the car was designed using CAD software, eliminating the measurement errors inherent to the original design.

The suggested donor car is a Ford Sierra. The book contains alternate suggestions for incorporating other donors.

Other Variations

The Locost is not to be confused with the similarly named Locust which is also a Lotus Seven inspired car. In contrast to the Locost's space frame inspired chassis, the Locust uses a ladder chassis and a body constructed from plywood skinned with aluminium.

McSorley Locost

The Champion Locost and the Haynes Roadster share similar chassis dimensions to the original Lotus Seven. Locost Builder [http://www.mcsorley.net/locost/ Jim McSorley] revised the Ron Champion design in order to accommodate wider engines, rear axles, and seats. In particular, the McSorley 442 design was referenced by [http://www.caranddriver.com/features/11304/features-review-the-homemades.html Car and Driver Magazine] in August 2006.

"Australian Modifications"

In Australia, kit cars must pass structural testing for certification for road use. This has led to a series of improvements to the Champion design, including increased reinforcement at the nose of the chassis and around the occupants. These modifications also increase the stiffness and torsional rigidity of the chassis and have been adopted in Locosts in other countries.

Various projects have analyzed the strength of the Locost Chassis under Finite Element Analysis for interests sake. The FEA is known to show the original Locost's design to be slightly under engineered.

Cost of Construction

While the title of Ron Champion's book claims to offer a means to build a car for £250, most Locosts are usually as much as ten times that cost or more.

The £250 figure does not include the cost of tools, which can equal the cost of the car or more. The book also is based on purchasing a Mk1 or Mk2 Ford Escort that has been rejected for road use by the British MOT. At the time of printing, Champion claims said cars could be purchased for £50. Escorts are now hard to find due to the popularity of the book.

The book gives some hints and tips on how to cut the costs for the build:
* Build the chassis from scrap metal instead of buying new
* Make your own fibreglass nosecone and wheel arches instead of buying them
* Use the rear seat from the donor or one from the junkyard instead of buying new race seats
* Use the donor gauges, steering wheel and rims instead of buying new
* Buy wrongly mixed paint at a discount and paint the car yourself
* Find some aluminium sheet metal at the scrapper(for instance from the side of a van) to use for the bonnet

Some builders have come up with additional cost saving tips:
* Use the sheet metal roof of the donor for the bottom of the chassis instead of buying new sheet metal
* Use the gas tank from a Saab 96 or Triumph Spitfire
* Use the headlights and chrome rims from an older Volvo 240 and an 8 inch stainless steel salad bowl from IKEA to make the headlights
* Make your own coilovers using Mini shocks and springs.

Even at ten times the £250, Locosts frequently cost far less than a car of similar performance.

Common Donor Vehicles

The car described in the Champion book is built using parts from a Mk1 or Mk2 Ford Escort with front spindles from Ford Cortina. Due to the dwindling supply of Escorts, the Haynes Roadster is based on mechanicals from the Ford Sierra.

In North America, the Toyota Corolla and Mazda Miata are popular donor cars. The Wankel engine-based Mazda RX-7 is also starting to become popular.

Many different companies make and sell parts and complete kits for building the car, some examples are MK Engineering (who have continued on the concept and now offer their MK Indy, based on the Ford Sierra), RaceTech with their Lada based ESTfield, Coveland Motorsports (who also makes a chassis for using Mazda Miata parts) [http://www.coveland7.com] , DD7 in Umeå, Sweden [http://www.rejsa.nu/forum/viewtopic.php?t=10104] and many more.

Racing

The Locost has produced one of the most successful championships in UK Club Motor sport, the Formula Locost. Organised by the 750 Motor Club the 2006 championship regularly sees over 40 competitors racing at circuits such as Brands Hatch, Donington, Thruxton and Silverstone, to name but a few. Running with very tight regulations and deliberately limiting costs, the 750 Motor Club have ensured affordable and close competitive racing for the enthusiastic amateur. While it is not really possible to build a race car for the £250 quoted in the title of the book by Ron Champion, it is probably the least expensive form of motor sport available in the UK.

While locost racing is not as popular in North America, Locosts are eligible to compete in several amateur racing formats under many governing bodies such as the SCCA and NACA. Grassroots Motorsports' $200X Challenge has a special category for Locosts and other kit cars.

External links

*
* [http://www.jordanmotorsports.com/locost Locost builders reference website]
* http://www.locost.ozcarnut.com (Australian build using MX5 parts - lots of pictures)
* http://www.locostcarclub.co.uk
* http://www.locostbuilders.co.uk
* http://iainseven.wordpress.com/ an Aussie build site with lots of pictures
* http://locostusa.com A site and discussion forum for North American builders
* http://locost7.info
* http://www.locostsa.co.za/ (South African Enthusiasts site)
* http://www.locostsweden.se
* http://www.cheapsportscar.net A build diary using a CMC chassis and a Miata donor
* http://www.mcsorley.net/locost/ (detailed drawings)
* http://www.750mc.co.uk (organisers of the UK Locost championship)
* http://www.tmcmotorsport.co.uk (website of a team competing in the UK championship, with links to other Locost websites)
* http://www.lora.c4.fr/ When two crazy french people decide to make it!!
* Ron Champion's homepage at http://www.ronchampion.net
* [http://www.locostusa.com/ Building a "Locost" style sportscar in America]
* http://www.funcar.org.uk Photographic diary of a Locost build. Comprehensive Locost links.
* http://www.mindspring.com/~robmk2 Locost RX7 based build with cosmo engine.
* http://seven.dfx.co.za/ Another rotary based Locost (RX7 engine & gearbox)
* [http://www.haynes.co.uk/forums/index.php Haynes Roadster Forums]
* http://www.projectlocost.org/ A locost project which has undergone engineering analysis
* http://www.sevenbuilder.com/ How Sevens are built, history, motorsports and vendor information
* http://www.jacinx.prv.pl