The development prototypes that begin testing this month will initially use modified Senna road car bodywork. The final Senna GTR shape - shown in simple form in a new design sketch - will be based around a chassis with wider track front and rear and centre-lock wheels.
The carbon fibre body has new, wider fenders, a larger front splitter and rear diffuser and repositioned active rear wing; these last two elements combining to improve aero-efficiency by 'coupling' the wing to the airflow from the diffuser, enabling greater - and more accessible - downforce at lower speeds.
A final vehicle weight is still to be declared, but the GTR will weigh less than the road-going Senna. In combination with the 814bhp output of the 4.0-litre twin-turbocharged V8 engine - an increase of 25bhp over the road-legal Senna - this will see the power-to-weight ratio comfortably exceed that of the road car. Together with torque of up to 800Nm, the result will be astonishing levels of response and performance.
The Senna GTR retains the active aerodynamics of the road-legal car - an advantage that would not be permissible in a homologated race car - which is a major enabler in generating the 1,000kg of downforce. The car has conventional double wishbone suspension, with the geometry, springs, dampers and anti-roll bars having been developed from the system engineered for McLaren's GT3 customer racing programme.
