Onyx Sports Cars

Onyx Sports Cars Ltd was a British kit-car manufacturer specializing in lightweight sports cars assembled from purpose-built bodywork and components sourced from mass-produced donor vehicles. The company occupied a niche within the United Kingdom’s enthusiast-oriented kit-car industry, where customers typically purchased a body-and-chassis package and completed the vehicle themselves using an existing engine, transmission, suspension, electrical system, and other mechanical parts. The company’s first model was the Onyx Firefly, introduced in 1993. The Firefly was based on the Fiat Panda, adapting the small Fiat’s front-wheel-drive mechanical package to a more overtly sporting kit-car format. The model reflected a common approach in the British kit-car sector: keeping the donor vehicle’s major mechanical systems lowered construction cost and simplified parts supply, while allowing the builder to create a distinctive body style. The Firefly later passed to Alphax Kitcars, which continued production from 2005 and marketed the car again in the British and European markets under the Alphax Firefly name. Onyx subsequently developed the Firecat, a two-seat open sports car introduced in 1995. Designed by David Golightly, it used Fiat Uno components and retained a front-wheel-drive layout. Builders could use the standard Fiat Uno powertrain or, optionally, the more powerful Fiat Uno Turbo engine. The Firecat remained in production for approximately five years, during which around 100 examples were sold. Its limited volume was characteristic of the specialist kit-car market, where production was driven more by enthusiast demand and individual builds than by mass-market manufacturing. The company also produced the Onyx Mongoose, a mid-engined sports-car design engineered around the Rover K-series engine. The engine and related components could be sourced from a Rover Metro or Rover 200 Series donor vehicle. This configuration gave the Mongoose a substantially different layout from the front-wheel-drive Firefly and Firecat, appealing to builders seeking a more performance-focused, rear-driven-feeling kit-car architecture and a central engine position. Another Rover K-series model was the Onyx Firefox, a two-seat open sports car designed to use the engine in a front-wheel-drive position. The Firefox was supported by enthusiast build documentation and project reports, reflecting the self-build culture surrounding Onyx products. Across its range, the brand’s proposition centered on accessible construction, donor-car compatibility, distinctive styling, and the ability for owners to complete and personalize their own cars. Publicly available reference material provides limited information about Onyx Sports Cars’ corporate ownership, management, manufacturing facilities, financial performance, and present trading status. The later transfer of Firefly production to Alphax Kitcars is documented, but there is insufficient evidence to establish whether Onyx Sports Cars itself remains active. It is therefore best characterized as a specialist British kit-car marque with a historically documented product range and an uncertain current operating status.

Onyx Sports Cars was a British specialist kit-car manufacturer whose products were designed for enthusiast assembly using mechanical components from donor vehicles. Rather than manufacturing complete cars at high volume, the company supplied distinctive sports-car designs that could be built around existing Fiat or Rover running gear. This approach was well suited to Britain’s established kit-car culture, in which builders sought a combination of low-volume styling, mechanical familiarity, and personal involvement in vehicle construction. The earliest documented Onyx model was the Firefly, introduced in 1993. It was based on the Fiat Panda and used the donor vehicle as the foundation for a compact sports-car conversion. The model demonstrated the company’s practical emphasis on using readily available production-car components rather than developing an entirely proprietary drivetrain. In 2005, Firefly production was taken up by Alphax Kitcars, which brought the design back to the British and European kit-car market under the Alphax Firefly designation. In 1995, Onyx added the Firecat, a two-seat open sports car designed by David Golightly. The Firecat used Fiat Uno parts and retained a front-wheel-drive configuration. An optional Fiat Uno Turbo engine provided a higher-performance alternative to the standard donor powertrain. The model was produced for roughly five years and is reported to have achieved sales of about 100 examples, making it a small-volume product even within the specialist kit-car sector. Onyx’s Rover-based models broadened its technical range. The Mongoose was a mid-engined design intended for the Rover K-series engine, with donor components available from the Rover Metro or Rover 200 Series. This layout distinguished it from the Fiat-derived front-wheel-drive cars and gave the model a stronger performance-oriented identity. The Firefox was another Rover K-series project, but used the engine in a front-wheel-drive position and was configured as a two-seat open sports car. Build pages and enthusiast reports associated with the Firefox and Mongoose show how the cars were supported and discussed within the self-build community. The available record does not establish a complete corporate chronology, including the company’s incorporation date, founders, ownership changes, factory location, or final operating date. It does, however, show a progression from the Fiat Panda-based Firefly to the Fiat Uno-derived Firecat and then to Rover K-series designs with different drivetrain layouts. The later continuation of the Firefly by Alphax Kitcars indicates that at least one Onyx design remained commercially relevant after the original company’s period of prominence. Onyx Sports Cars should therefore be understood primarily as a historically documented British kit-car marque rather than a conventional high-volume automobile manufacturer. Its current status cannot be confirmed from the cited public material.

• 2005

  Firefly production moves to Alphax Kitcars

  [1]Onyx Sports Carsen.wikipedia.org

  Alphax Kitcars began producing the Firefly and marketed it in the United Kingdom and Europe as the Alphax Firefly.

• 2000

  Approximate end of the Firecat’s five-year production period

  [1]Onyx Sports Carsen.wikipedia.org

  The Firecat’s reported five-year production run concluded around this point, with approximately 100 cars sold. The exact final production year is not explicitly stated in the reference material.

• 1995

  Onyx Firecat introduced

  [1]Onyx Sports Carsen.wikipedia.org

  The Firecat entered the range as a two-seat open sports car designed by David Golightly and using Fiat Uno mechanical parts.

• 1993

  Onyx Firefly becomes the company’s first documented car

  [1]Onyx Sports Carsen.wikipedia.org

  Onyx Sports Cars introduced the Firefly, a compact sports-car kit based on Fiat Panda components.

A specialist British kit-car marque offering attainable, donor-based sports cars for enthusiast builders, with an emphasis on compact packaging, home construction, and reuse of Fiat or Rover mechanical components.

• Kit car · 1993

  Onyx Firefly

  The Firefly was Onyx Sports Cars’ first documented model, introduced in 1993. It was based on the Fiat Panda, using the small Fiat as a donor platform for a more sporting body and self-build vehicle concept. The design was later produced by Alphax Kitcars from 2005 and reintroduced to British and European customers as the Alphax Firefly.

• Open sports-car kit · 1995

  Onyx Firecat

  The Firecat was a two-seat open sports-car kit introduced in 1995 and designed by David Golightly. It used Fiat Uno components in a front-wheel-drive layout, with the option of fitting a Fiat Uno Turbo engine. The model remained in production for approximately five years and achieved reported sales of around 100 examples.

• Mid-engined sports-car kit

  Onyx Mongoose

  The Mongoose was a mid-engined Onyx sports-car design intended for the Rover K-series engine. Donor powertrains and related components could be sourced from the Rover Metro or Rover 200 Series. Its central-engine layout differentiated it from the company’s front-wheel-drive Fiat-based models and targeted builders seeking a more performance-oriented project.

• Open sports-car kit

  Onyx Firefox

  The Firefox was a two-seat open sports-car kit designed around the Rover K-series engine in a front-wheel-drive position. It was supported by enthusiast build documentation and reports, consistent with Onyx’s focus on home-built cars using donor-vehicle mechanical systems.

• 2005

  Transfer of Firefly production to Alphax KitcarsM&A

  Background

  The Firefly was one of Onyx Sports Cars’ earliest products and was based on Fiat Panda components. By 2005, production and market support for the design had moved to Alphax Kitcars.

  Action taken

  Alphax Kitcars took over production and reintroduced the vehicle in the United Kingdom and Europe under the Alphax Firefly name.

  Aftermath

  The Firefly design continued beyond its original Onyx branding, but the available sources do not specify the legal form or commercial terms of the transfer.

  Source

1. 1Onyx Sports Carsen.wikipedia.org
2. 2Onyx Sports Cars archived websiteonyxsportscars.f9.co.uk