The VIN number series represented a change from each model having it's own numbering series defined by a model code prefix, ie VA for a Sprint or WF for an 1850, to an overall numbering series, where the next Dolomite off the line got the next number in the series, irrespective of model, 1300 or Sprint, it didn't matter.
So we're discussing here the possibility of the factory building over 2000 of all models of Dolomite per MONTH for the last 4 remaining months of 1979 (Sept 1st to Dec 31st) in order to make 8101 a 79 built car which would be elegible for free VED on April 1st this year.
On the whole, I consider it extremely unlikely but not totally impossible. Remember, in 79, the factories were already winding down, the GT6 finished in 73, TR6 died around 76, the Stag and 2000/2.5 ranges in 78. The Speke plant was closed around this time and production of the last 3 models, the Spitfire, Dolomite and TR7 was split between Canley and the Rover factory in Solihull. Triumph as a marque was dead, just not quite buried yet! The abomination of badge engineering that was the Triumph Acclaim was built at Cowley in the old Morris plant and Canley was already closed by then.
The MOST practical way of finding out is, as Alun suggests, to go online and buy the single piece of Heritage info that will confirm one way or the other. But you might just find someone with a VIN numbered car close to yours which has a confirmed build date (remember ANY model will do) to give you a clue!
I have, on my drive at the moment, a June 79 built, VA30xxx chassis numbered Sprint that was not registered till May 1980, a combination of Russet brown paint, the model being 8 years old and the less desirable Automatic transmission being a difficult proposition for the salesmen I should think! But these throwbacks are quite rare, few cars lasted more than 3 months in the showrooms before sale unless there was a good reason for it, as in the car I mentioned above. So I wouldn't hold your breath!
At worst, you will only have to wait till 1/4/2021 for your free VED!
'73 2 door Toledo with Vauxhall Carlton 2.0 8v engine (The Carledo)
'78 Sprint Auto with Vauxhall Omega 2.2 16v engine (The Dolomega)
'72 Triumph 1500FWD in Slate Grey
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