Features

The showpiece for Ewing Senior's talents is the roof system, a simple arrangement of panels fixed in place by metal pins, and removed by flipping a rear-mounted catch on each. The side pair can also be partially opened to vent out to the rear, or removed to leave a T-top.

Rumbling along late at night, with valet parkers begging us to pull up in front of the restaurants they work for, the only justifiable option is to go fully roofless and soak up the attention.

The name chosen for his car is written along its sills: GTX1. This is a homage to a similarly named open-topped racer that won the Sebring 12-Hours back in 1966, a priceless piece of Ford's heritage.

Unfortunately, rumour suggests that this was broken up soon after its victory and now lies buried in the foundations of an apartment block near Los Angeles International Airport, following questions from customs officers about why import duty had never been paid on it.

The choice, this (surely, apocryphal) tale implies, was between stumping up or discreetly disposing of the car.

The new GTX1 is no swift chop job of the other variety, either. Strengthening is built into the header rail and sills, while the carbon-fibre rear clamshell is completely redesigned, with sharply humped twin cowlings maintaining the flow of the car's sleek profile from front to rear, even with the roof removed.

Another addition is the pair of see-through panels built in above the 5.4-litre V8 engine, providing a voyeuristic rear view of a supercharger setting about the job of releasing up to 550bhp.

The noise is spectacular in a deeply muscular and unashamedly brash manner; the delivery of performance on a similar scale.

With the roof gone, you're that much closer to the sensations being thrown in your direction.

There's the long-hitting, linear surge that an engine delivering 450lb ft of torque from just 1,500rpm is capable of providing, joined by the shriek of a supercharger spinning up and the loud ticking of 16 fuel injectors firing into eight cylinders, immediately behind your ears.

The forces are borderline seismic, adding to the loadings the GTX1's cut-down body has to be capable of facing up to. Still, somehow, the extra stiffening has worked, the steering retaining its detail, and rattles and shimmies failing to intrude, even over rough surfaces.

The ride assists, retaining an edge of suppleness even with this car's lowered suspension in place.

Some of the regular GT's inherent weaknesses remain, including a gearchange so long in its shift action that it forces you to perform the arm movements of a Nordic skier whenever you reach for another of the six ratios.