It was only a mild admonishment, but the start-line marshal on the Goodwood Festival of Speed Supercar run meant business: "No mobile phones".

Sitting snugly in the open cockpit of the new Morgan Plus 8 Speedster with a clear view of blue sky, trees and the hallmark louvred bonnet, I couldn’t resist the obvious last-minute photo opportunity – a quick snap of the famous black-and-white chequered arch that marks the S-T-A-R-T of the 1.2-mile run up Lord March’s front drive.

Snap taken, I stowed my iPhone and Morgan R&D manager Mark Reeves gunned the rumbling V8-powered Plus 8 Speedster off the start line.

Reeves is experienced enough to make this a safe and secure demo run – rather than some hot qualifying lap – so the Plus 8 Speedster rounds the first corner neatly and well in shape, accompanied by a throaty bellowing from the BMW V8, and squirts rapidly up the straight in front of Goodwood House.

Reeves has already exploited the BMW V8’s throaty exhaust and crackling over-run as we make our way from the Supercar Paddock through various holding areas to the start of the run. It must be making a heck of an impression outside the car, because inside it sounds magic.

As we waited our start time I’d already decided that the minimal polycarbonate Speedster screens would do little to calm the airflow over the Morgan’s sensuous, but-not-wind-tunnel-honed, body.

However on the run our helmeted heads experience only a light ruffling as Reeves reaches a v-max around 170km/h (about 105mph). This left-hand-drive demonstrator has a kilometres per hour speedo, and a glance at the round dial as we arrow towards ‘The Wall’ – Goodwood’s right-left combo defined by an uncompromising flint wall – shows a shade over 100mph.

"Just a gentle run for the first go," smiles Reeves. For the afternoon’s run, he is already planning to let a little air out of the 18in Yokohama tyres, which he reckons are a touch over-inflated.

Although from the passenger seat, the few mild bumps on the smooth hillclimb appear to show the Morgan’s chassis as reasonably compliant while the nimble manner in which the Speedster flicked right-left through ‘The Wall’ suggests a nicely sorted chassis and responsive steering.

Just 60 Plus 8 Speedsters will be built and they’re all scheduled to be finished by the end of 2014, Morgan’s centenary of car-making at its legendary Pickersleigh Road factory in Malvern.

At a shade under £70k, the Speedster is about £15k cheaper than the Plus 8 soft-top, reflecting its stripped-out equipment count, such as roof and windscreen.

But given the rumbling V8, Morgan’s timeless styling and the effectiveness of the aeroscreen, who needs such practicalities for a great drive on a sunny day?