Abu Dhabi, United Arab Emirates - With just a month to go before the 2017 World Rally Championship kicks off at the traditional Monte Carlo Rally, Citroen Racing has released full details of the new C3 WRC, built to the 1.6-litre turbopetrol four Global Racing Engine formula.
Based on the architecture of Citroen’s World Touring Car Championship winning car, it has a block machined from a solid block of aluminium (the most precise, but also the most expensive way to make anything), gear-driven dual overhead camshafts, four valves per cylinder and Magneti Marelli direct fuel-injection.
But the biggest boost (if you’ll forgive the pun!) in performance comes from increasing the diameter of the turbo restrictor plate from 33mm to 36mm, increasing maximum power by about 20 percent to 280kW at 6000rpm. Maximum boost is limited under FIA GRE regulations to 2.5 bar, however, so peak torque remains much the same as the previous generation - about 400Nm at 4500rpm.
If those figures seem a little conservative, that’s because each car is allowed only three engines for the whole season, so durability becomes a key concern. Nevertheless, the extra power, wider track and uprated suspension and aero kit are going to make the 2017 cars a serious handful when driven in anger, in line with the FIA’s stated intention of making the World Rally Championship more exciting to watch.
The light stuff
Power reaches all four wheels via a semi-automatic six-speed sequential gearbox with paddle shift, a centrally-controlled hydraulic differential and self-locking mechanical limited-slip differentials on the front and rear axles. Braking is by ventilated discs and four-pot callipers all round, water-cooled in front.
Each car starts life as a standard five-door C3 body shell; the rear doors are welded shut and a tubular roll cage welded in, as much to support the upgraded suspension – including tilted dampers adjustable for high and low-speed compression as well as rebound damping – as to protect the crew, while most of the outer panels are replaced with carbon fibre.
These feature dramatically flared wheel arches (the 2017 regulations allow for 55mm extra track width), bulldozer-like front aprons (with different depths for tar and gravel stages) a protruding rear diffuser and a seriously sexy biplane rear wing (Subaru, eat your heart out). The whole car weighs just 1190kg, giving it a power-to-weight ratio of 235kW/ton.
The human factor
The works team will field between two and four of the new cars in each of the 13 rounds making up the 2017 World Rally Championship, led by development driver (he’s also a trained engineer) Kris Meeke and navigator Paul Nagle, and one or more of young crews Craig Breen and Scott Martin, and Stephane Lefebvre and Gabin Moreau, with a fourth car where appropriate for team sponsor and former multiple Middle East rally champion Sheikh Khalid Al Qassimi and navigator Chris Patterson.