It has also been noted that none of the suggested reasons for cancellation are a good match for when the main production ceased about the end of June 1977.

The cancellation was with that of the proposed Dolomite replacement Triumph SD2, which was also to use the 16-valve version of the slant-four engine and an electronic fuel injection system that should have met US emissions requirements.

These were cancelled after BLMC went bankrupt in late 1974 and was essentially nationalized under the almost £3 billion plan in the 1975 Ryder Report (British Leyland), which was still in force well into 1977.

[1] Hence, it is possible that had Triumph produced the TR7 Sprint and TR8 to UK specification, as was apparently planned at one time,[3][8] there likely would have been significant debate of their relative merits.

The same source also states that "A related assessment exercise for the TR7 was the '90 day corrosion test', for which a prototype was built without the usual zinc primer or anti-corrosion treatments and the body painted white, the best colour to show up any rust streaks."

A Triumph engineer is quoted as saying, "this prototype was run around a variety of road surfaces under wet conditions and then the damp areas were checked.

This statement is itself based only on most of the cars having "UK PRESS VEHICLE" handwritten in felt-tip pen on their build cards.

[20] According to a letter from the then archivist, reporting the research of the BMIHT records, "This car was originally intended for display at the 1977 [ Daily Express ] Motorfair in Earls Court, London.

There are a number of auxiliary engine parts specific to the TR7 Sprint, and not used on the Dolomite Sprint engine: the cast steel exhaust manifold (RKC2788),[1] the front pipe of the exhaust system (which has been remanufactured, RB7385), and a water transfer plate at the back of the cylinder head (also remanufactured, RB7240).

It appears that the exterior of the pre-production TR7 Sprints was, and presumably the production cars would have been, indistinguishable from the TR7 of the day, apart from the decals and side stripes.

Whereas, these decals form part of the set displayed on the FHC TR8 shown in the TR8's homologation papers (FIA #654), identifying it as a "Sprint TR7 V8".

There is also a published photograph of what appears to be a US Spec., 1977 year model car carrying side stripes with the word "Sprint" on the rear wings, the caption to which states "The sides of the TR7 Sprint were supposed to have received this striping treatment, designed by John Ashford, had the car gone into production.

[30] They are also shown in a series of 6 "TR7 Sprint Homologation" photographs in the BMIHT Film and Picture Library, taken on 1 November 1977 before the car was sold-off by BL.

[31] An owner's handbook, AKM 3967, was also produced for TR7 Sprint in 1977, but is apparently for the 1977 year model: it shows the interior light in the headlining not the doors.

There is a story at one TR7 related website ([9]), and already current in the 1980s, that John Davenport, "needed white cars without sunrooves [sic] and these were the nearest four."

Equally anecdotally, a more complete reproduction of the 1991 owner written article from the TR Driver's Club magazine states "Although the SJW TR7V8 rally cars began life as TR7 Sprints, the rally cars were scratch built using bodies taken off the line and prepared by Safety Devices.

[34] Rally journalist and historian Graham Robson refers to the "famous 'inventive homologation' skills" of Bill Price, then workshop manager at BL Special Tuning (ST) at Abingdon, and to him "perhaps, taking lessons from Ralph Broad, who was an old hand at the black art of 'reading the rules'", and states that "Bill [Price] managed to gain approval for a TR7 which was only loosely related to the production car."

Such optional equipment could be recognized as "bolt-on option kits", which had to be "available freely at the manufacturer's or his dealers' for any one wishing to purchase it" - as would have been the case with the 16-valve head and its drive (pistons, carbs, and manifolds could be changed freely for Group 4), and for the overdriven gearbox, which would have been available as spare parts for the Dolomite Sprint (the heavy duty axle was homologated for Group 3, and thus 4, by a different means).

But when the 16-valve TR7 was homologated for Group 4 in October 1975, the 100-off rule did not require the production of any 16-valve engined road cars, only the kits needed to equip them.

A number of other modifications were listed in the amendment (1/1V) to the TR7's homologation for the Group 4 TR7, such as larger front callipers and rear disk brakes.

[36] Other modifications that are not listed in the papers, such as suspension components and axle locating arms, etc., were given as freely allowed to be changed or added without need of being specifically recognized as part of the homologation process.

[12] As a result, several teams had, at this time, to remove similar equipment from their cars, including the Toyota Celica, Vauxhall Chevette HS,[note 6] and Lancia Stratos.

"[1] This expectation is supported by what happened to the 25 or so cars of the failed O-series engine TR7 development programme, which were either scrapped or converted to TR8s before sale.

However these were needed for its homologation approval (granted 1 April 1978), and would have been covered by the same FIA requirement to be "meant for the normal sale".

[14][20] It has been an issue of conjecture and debate if the TR7 Sprint ever really was intended for full series production as a catalogued model and why so few were made if it was.

[1][3] However, this industrial action is itself blamed, ultimately, on the "replacement of the aristocratic Lord Stokes with South African businessman Michael Edwardes" as managing director, announced in Nov 1977.

[7] These events therefore occur well after the main production ceased in early July 1977, and probably too late to be responsible for the change of status indicated by the start of the transfer of the press garage cars out of the keeping of Sales and Marketing, on 9 November 1977.

[20] Another reason given for the cancellation is that "the Marketing department killed it because the 0-60 acceleration times were identical to the 2V engine with little increase in top speed."

[44] This cancellation with SD2 in 1975 is supported by the 1975 Ryder report, which followed the bankruptcy of BLMC, provided the nearly £3 billion pound rescue plan for BL through ownership by the National Enterprise Board,and identified BL’s critical need for rationalization of the range of competing models and engine types produced by BLMC.

Further, their transfer out of the keeping of sales and marketing follows only 8 days after the TR7 Sprint Homologation pictures were apparently taken, which, presumably coincides with their inspection prior to granting the second approval of the 16-valve head.