Some cautionary reading for anyone who’s about to put a deposit on Toyota’s go-faster GT86 sports car – the TRD. We figured one yesterday, putting it through the same handling, braking and acceleration tests as we did the standard ’86 last year. Not for a full road test, mind; just to find out what it’d do.

At this point it seems only fair to point out that the Toyota Racing Developments version of the car isn’t an especially trick machine as tuned sports cars go. The departures from standard ’86 specification include larger alloy wheels, wider and stickier Yokohama Advan Sport tyres, a new exhaust, a revised rear diffuser panel and a sporty body kit.

Officially there’s no extra horsepower on offer here, no extra braking power and no stiffer suspension setup either. There’s an adjustable chassis, upgraded brakes and lighter forged alloys in the TRD catalogue, but they’re options: they’re not included for your £6.5k premium over a standard GT86.

Given all that, you wouldn’t expect the TRD to be any quicker accelerating than the standard car. In fact, it’s slower. On the same tarmac where we tested the GT86, the tuned car actually took a tenth of a second longer to hit 60mph from standing (7.4sec versus 7.5) proving more difficult to get off the line cleanly without bogging down with too few revs, or overheating the clutch with too many. Might have been the extra drag of the body, or tightness in the engine – but by 100mph the TRD was another six tenths slower than the standard car.

On MIRA’s dry handling circuit, the TRD demonstrated slightly greater cornering speed than the standard ’86 – but not as much as you might think. At our reference corner, it produced 1.01g of lateral grip compared to 0.99g for the ‘lesser’ version. The TRD’s mean laptime was 1min 20sec exactly, the GT86’s 1min 20.6sec. And on the wet handling circuit, that position was more than overhauled: TRD – 1min 26.4sec, GT86 – 1min 22.1. The new Ford Fiesta ST will go around there in 1min 15.7sec, just for the record.

Now combine all of that with the gospel we’ve been preaching about the GT86 for more than a year now: that its balletic genius is entirely dependent on those ‘Goldilocks’ grip levels (not too high, not too low, just right), which allow you to have so much fun at relatively low speeds. Consider that, faster or not, the TRD car is marginally less of a joy than the standard car, even on a dry circuit: that it just isn’t quite as agile or minutely throttle-adjustable with the electronics off. The TRD can actually understeer when you goad it mid-corner – heaven forbid. And it’s not only much slower and less grippy but also less sublimely controllable in the wet.

Maybe it’s the most canny marketing tactic ever conceived - one to make the £25k model look all the more brilliantly priced. Whatever it is, you’d be pretty misguided to spend more and get less with this car. Regardless what the salesman tells you, don’t be fooled. Put your £6500 towards fuel, consumables, track days, anything: just don’t put it towards a GT86 TRD.