By Andrew Ganz
Thursday, Dec 5th, 2013 @ 10:38 am

In a surprise move, Ford has decided to unveil the 2015 Mustang Convertible alongside its coupe sibling. It was previously believed that the drop-top was still months away from greeting the public.

So far, our only look at the convertible comes from a tweeted photo and a video of the 2015 Mustang's debut in Sydney, Australia. Ford will likely release official images later today, but in the meantime we can tell the open-air 'Stang will continue to use a fabric roof with what appears to be a manual tonneau cover.

While official details have yet to be released, expect the convertible's mechanicals to mirror those of the coupe.

That would mean carryover 3.7-liter V6 and 5.0-liter V8 engines - albeit with the more power than before (official figures to come). The coupe's 2.3-liter EcoBoost four-cylinder could also make its way into the convertible's engine bay, making 305 horsepower and 300 lb-ft. of torque (the latter of which comes at just 2,500 rpm). Like in Ford's F-Series pickups, the turbo engine is actually an extra cost upgrade even though it's the smallest displacement on offer.

Fuel economy numbers should be announced closer to the Mustang's on-sale date, but improvements across the range are expected.

Six-speed Getrag manual and six-speed automatic (with new paddle shifter) transmissions will be available. The automatic is a conventional unit, not the long-rumored dual-clutch.

Bringing things to a halt are larger brakes, which grow from 12.6 inch front rotors to 13.9 inch units with the selection of the optional Performance Package on four and six-cylinder models. Selecting the V8-powered GT nets 15-inch Brembo front units.

Underneath, the Mustang's rear solid axle has been chucked for only the second time ever (the SVT Cobra model briefly offered an independent rear setup). Up front, Mustang gains a new MacPherson strut/double ball joint design that takes up less space and offers what's said to be improved handling.

Between the suspension changes and Ford's use of lighter materials, the Mustang coupe checks in about 200 lbs. less chunky than before - expect the convertible to benefit from a similar reduction.

Inside, Ford's MyFord Touch infotainment system will be available on the Mustang. All models will come standard with a proximity key and the automaker's Sync connectivity system. Toggle switches just below the screen will control a number of performance features - including the car's electric power steering.