Triumph GT6 Buyer's Guide
The GT6 is the Spitfire's fastback sister with the Vitesse's two-litre straight six under that long bonnet, which earned it the "poor man's E-type" tag in period and makes it the most collectable of the small Triumphs today. Our single sold result, a 1972 car at £14,442, shows where a good one now sits: comfortably above equivalent Spitfire money.
Know your generations
Three marks in seven years. The Mk1 (1966–1968, 95bhp) is the purest shape but carries the Spitfire's swing-axle rear end, which will lift a wheel and tuck under if provoked; period road testers complained, and Triumph listened. The Mk2 of 1968–1970 (GT6+ in America, 104bhp) answered with rotoflex-jointed lower wishbones at the rear, transforming the handling, plus a raised front bumper. The Mk3 (1970–1973, 104bhp) got the cleaner Spitfire MkIV-style rear and is the most usable; the very last cars reverted to a cheaper swing-spring rear that works well. Overdrive is the option worth seeking on all of them.
What to pay
One sale in our records: £14,442 for a 1972 GT6 Mk3 in March 2026. Two live listings frame the condition spread well: a 1972 car estimated at £2,500–£3,000 sits at the project end, while a 1973 example carries an £11,500–£13,500 estimate, consistent with our sold result. Read the market as roughly £2,500 for something needing everything through to the mid-teens for a car ready to use. Mk1s and well-restored Mk2s trade on rarity and can exceed Mk3 money nationally, though our data cannot yet evidence that.
What goes wrong
Chassis first: the GT6 uses the Herald-family separate chassis, and the outriggers, main rails around the rear suspension mounts and the front suspension turrets all rot. The one-piece forward-tilting bonnet hides accident history badly repaired; check panel gaps and the fit around the headlamps. Rotoflex cars (Mk2 and most Mk3s) eat their rubber doughnut couplings; a set is not dear but the job is awkward, and clonks from the rear on the test drive mean they are due. Front trunnions must be greased with oil, not grease, or they seize and snap the vertical link, which is as alarming as it sounds. The six itself is understressed and good for big mileages; watch for crankshaft thrust washer wear (check for end float at the front pulley with the clutch depressed) because a dropped washer wrecks the block. Cabin heat soak is a design feature; a rebuilt car with added bulkhead insulation is a car someone loved.
Our view
The GT6 is the small Triumph with a genuine long-term case: six cylinders, a shape that needs no excuses, complete parts availability through the club suppliers, and a separate chassis that makes restoration honest work rather than dark art. A Mk3 with rotoflex done and overdrive, at or under our £14,442 result, is the buy. The £2,500 projects only make sense if the chassis is good; everything else can be bought, a rotten frame swallows the difference instantly.
