Triumph TR8 VIN Decoder

Some personal-export cars, sold to Americans in Europe, carry a second number as well: triumphtr8.com finds a European-style number stamped in the rain gutter of the boot (trunk) on some, and a hastily stamped number near a suspension turret on others.⁠source 1​source 2​source 4​source 5​source 6

Before October 1979 a chassis number began with three letters: the plant, C for the TR7 and TR8 range, and a letter for the specification.

The TR7's letters are different: L, G and W for its coupés, H for the 1977 Sprint coupés and, at Canley, T for its convertible. Suffixes after the number add detail: U for North America, L for other left-hand-drive cars, F for a five-speed gearbox (transmission), A for an automatic, C for exhaust control and M for Canada. The Canley TR8 numbers have six figures: TCN 150001 to 150198 for the 1978 model year and 160001 to 160142 for the 1979 model year, most of them probably never used, the TR Drivers Club thinks, and TCV from 200001. The Speke coupés' range is printed in two ways, and the coupé's page gives both.⁠source 1​source 7

From October 1979 the TR7 and TR8 took a 14-character number, though a few TCV convertibles, the TR Drivers Club notes, kept the old prefix with a serial in the new series. Its first eight characters describe the car and the last six are its serial:

The serials ran in one series for every TR7 and TR8. Canley used 200001 to 215080, from October 1979 to August 1980. Solihull used 400001 to 401918 for the 1980 model year, from April to September 1980, and 402027 to 405636 for the 1981 model year, to May 1981; 402001 to 402026 were built at Canley in May and June 1980.

From May 1981, as new American and Canadian rules required, the North American cars had a 17-character number, with three letters in front, the engine and body shown by digits, and a check digit:

The check digit is worked out by turning each character into a number, multiplying them by 8, 7, 6, 5, 4, 3, 2 and 10 for the first eight places and by 9 down to 2 for the last eight, adding the results and dividing by 11: the remainder is the check digit, written X when it is 10. The SAT cars took serials from 406001, and the TR Drivers Club gives 408534 as the last. triumphtr8.com, which lists the factory's numbers, is blunt about a car without one:

The British pilot cars have numbers of their own: TPADV7A for a manual car and TPADV3A for an automatic, with T or A after them for Canley or Solihull. The second batch built on the line, and one methods-build car, are stamped TPVDA7AA, with the V and the A transposed, on their build records as well as on the cars, which triumphtr8.com calls a reliable way of picking out that batch. One genuine car, the automatic methods-build car 402290, carries a TR7 number and a TR7 plate, and Heritage records it as a right-hand-drive TR8.

The plates vary in the same way. The British TR8 plate, part TKC6764, gives a gross weight of 1,420 kg with the weights on the right, where the TR7's, TKC4542, gives 1,340 kg on the left. Reproductions of the TR8 plate are sold, and triumphtr8.com notes how they differ: on an original the first 0 of the figures "031013" lines up with the gap under "BL", towards the left, while a reproduction has those figures in the middle and larger lettering for the paint and trim codes. The Triumph Wedge Owners Association leaves the details of the British and prototype cars out of its own decoding pages:

A TR8 engine number has a two-figure prefix ending in E:

Test and development engines may carry EXP instead. triumphtr8.com's rule of thumb is that "Any other letter after the number other than E almost certainly means it's not factory". The 12E and 13E engines fit the carburettor TR8 that the California Air Resources Board certified for the 1979 model year. The highest injected engine number that James TenCate of the Triumph Wedge Owners Association traced, 14E00799, is, with Lucas's order for injection systems, the basis of his estimate of how many injected TR8s were built. The five-speed gearbox's number begins 15A, the Borg-Warner automatic's 051N and the axle's CK. An engine number by itself proves nothing about the car it sits in, since a TR8 engine may have come from a scrapped car.⁠source 2​source 10​source 6​source 11​source 12

The body shell carries its own number, which shows the body type and the steering side.

triumphtr8.com warns that "Many body plates have been lost over the years and cars re-shelled so they are a guide only". Some cars that left BL by the back door were registered on their body numbers alone, having lost their chassis plates.⁠source 2​source 9​source 13

None of these proves a TR8, since each can be fitted to a TR7, but a car that lacks several deserves questions.

The British Motor Museum issues Heritage Certificates from the build records in its archive, giving what the factory recorded of a car's build and despatch. For any car whose number is unusual, whose history is special or whose identity is in doubt, triumphtr8.com treats one as the least that will do. TenCate thought it "pretty cool to have a 'birth certificate' for your car".

A certificate's evidence is the factory's record. A note added to it later is a claim like any other and has to be checked: triumphtr8.com describes a case in which an unverified story was added to a car's certificate and later withdrawn by the museum's archive. The records can mislead in smaller ways too: triumphtr8.com cites a TR7-numbered development car whose certificate says it was despatched to the United States while the test fleet's records keep it in Britain.⁠source 3​source 2​source 11​source 13

triumphtr8.com lists what does not make a car a TR8: a body number alone, which is often what is left when a scrapped car has lost its chassis plate; a chassis number that is invented or wrong; letters from former owners, which are opinion; photocopies of registration documents, which are often altered; badges and trim, which are easily added; and an engine number on its own. Auction descriptions are not proof either, since the auction houses' own terms say they are supplied by the seller and not verified. Stories of factory right-hand-drive conversions, press cars and development prototypes need documents behind them, and the coupé's page and the right-hand-drive page explain why so few have any. A TR7 given a V8 is not a fake, unless it is sold as a TR8; TR7 V8 conversions tells how they were built.⁠source 13​source 2