the TR7 and TR7 Sprint have virtually identical engine blocks. As a result, there are a number of such converted TR7 models around: "There are a [comparatively] large number of privately built Sprint conversions about ... Buyers should beware of this if they are asked a premium price for an alleged 'genuine' TR7 Sprint." Lynx While the TR7 was under development in the early 1970s, a 2+2 fastback derivative, codenamed Lynx was also planned. The Lynx had a wheelbase stretched by , the Rover V8 engine, with the rear axle from the Rover SD1. Scheduled for launch in 1978, the Lynx was cancelled when the Speke factory was closed. Broadside In early 1979, a joint MG-Triumph project to produce a new sportscar based on the TR7 was started under the name Project Broadside. This was based on the TR7, with a wheelbase stretched by , with either an O-Series or Rover V8 engine, and both drophead and fastback body styles. Project Broadside was cancelled later in 1979, owing to a lack of funding. Examples of both Lynx and Broadside can be seen at the BMIHT, Gaydon, England. Boxer During the latter part of 1979, as an exercise in badge engineering, another MG version of the TR7 was developed under the codename Boxer as a potential replacement for the MGB. Various concepts were presented and ultimately a design from BL's American headquarters at Leonia was accepted. Major changes to the standard TR7 hardtop were the addition of a MG-type grille to the nose panel, headlights similar to those of a Porsche 928 and a new tail panel with light units from a Rover SD1. The proposal was ultimately rejected on the grounds that the car was insufficiently different from the TR7. O-Series Engined TR7 About 25 or so prototype/development TR7s fitted with the BL O-series engine were built. Build dates are not currently known, nor when the programme was cancelled. However, there are records showing these cars were either partly scrapped to rolling shells or converted to TR8 spec., before being sold off in 1983. At least one of these O-Series TR7s (KPH 537V) was fitted with an early (Canley developed) version of the O-Series turbo-charged engine. This was recorded as being the fastest ever Triumph on the test track at MIRA achieving an average lap speed of and a flying speed of - both figures being almost faster than the