The spider version McLaren MP4-12C has just been unveiled by the British sports car manufacturer. The vehicle is already available for ordering through the 38 McLaren retailers in 22 countries, and the only thing that differentiates this version from the coupe, is its retractable hard top (RHT).
Antony Sheriff, McLaren Automotive Managing Director said that “While the 12C is the technological essence of a race car, the 12C Spider incorporates an additional dimension. 12C Spider owners will love the opportunity to lower the roof and hear the unhindered howl of a V8 twin turbo engine at full throttle. It undoubtedly enhances an already euphoric 12C driving experience.
“The 12C Spider delivers all the thrills characteristic of a high performance roadster, and yet transforms into a raucous track beast at the flick of a switch. I can’t wait to see it on road and track with customers later this year.” 
The McLaren MP4-12C will cost 195,000 GBP in the UK and under its skin customer will find the same 3.8-litre twin-turbo V8 that is also powering the coupe, which means output figures of 625 HP (616 bhp) sent to the rear wheels via a 7 Speed SSG dual-clutch transmission.
Due to its increased drag coefficient, the spider version will accelerate from 0 to 100 mph 0.1 seconds slower than the coupe, meaning 6.1 seconds instead of 6.0, while nought to 124 mph will take 9.0 seconds flat instead of 8.8 seconds. The top speed has also been slightly affected, as it is now 204 mph instead of 207 mph but the 0 to 62 mph time remains the same at 3.1 seconds. 
The 2013 McLaren MP4-12C Spider weights 40 Kg more than the regular version due to the addition of the convertible roof system, and speaking about the roof, the automaker claims it can be operated at speeds of up to 19 mph (30 kmph) and that it takes 17 seconds for it to be raised or lowered.
When the roof is up, McLaren says that the area under the tonneau can be used as an additional luggage space, as it provides 52 litres worth of storage.
In terms of safety, McLaren has equipped the MP4-12C Spider with a passive Roll Over Protection System while inside the seats, the buttress area contains a steel structure
designed to absorb impact energy.

Source: McLaren