Ferrari 488 Pista Spider shown at Pebble Beach

Ferrari has surprised visitors to this weekend's Pebble Beach Concours d'Elegance by unexpectedly revealing the 488 Pista Spider.

Appearing just five months after the Italian supercar-maker pulled the drapes off the 488 Pista coupe at this year's Geneva motor show, the track-suited roadster wasn't expected to be unwrapped until the Los Angeles motor show this November, at the earliest.

Sharing the same uprated 3.9-litre twin-turbo V8 as the coupe, the Spider produces the same 530kW and 770Nm.

Despite a considerable weight penalty of around 91kg over the hard-top, Ferrari claims the spider is capable of matching the coupe's 2.85-second sprint to 100km/h.

It's only on the dash to 200km/h that the extra mass catches up with the hard-charging convertible, with Ferrari claiming the 488 Pista Spider takes eight seconds – 0.4sec slower than the lighter coupe.

Top speed, meanwhile, for the Spider is the same 340km/h claimed figure as the hard-top – because the Spider comes with a completely revised aerodynamic package that's claimed to match the coupe for efficiency.

The hard-core Spider also comes with the Ferrari Dynamic Enhancer tech that applies brake pressure to improve cornering.

Keeping weight down, the Pista ditches its carpets and sound deadening and gets fabric door straps instead of an internal door handle and the option of new Australian-made carbon-fibre wheels that are said to be 20 per cent lighter than the standard 20-inch alloy rims.

The Pista Spider is said to be the 50th convertible Ferrari model ever made, and appropriately the show car revealed in California is claimed to be finished in the car-maker's Pebble Beach blue stripes, matched with contrasting white paint.

Ferrari has not yet announced how many 488 Pista Spiders it plans to make, nor has it confirmed how much of a price premium the drop-top will command over the coupe, which sells Down Under for a sobering $645,000.