Aston Martin has announced that that the naturally aspirated 6.5 litre Cosworth V12 designed for its Valkyrie supercar will after all contest the World Endurance Championship including Le Mans. The Valkyrie road car had originally been intended to contest the current Hypercar (LMH) division of the WEC but that plan had been dropped when IMSA LMDh cars were admitted on a performance balancing basis.

Aston Martin had planned to recoup some of its investment in the Valkyrie race project through the sale of LMH customer cars. However, it was clear that an LMDh Prototype is a far less costly way of seeking Le Mans glory than a racecar derived from a £2.5 million roadcar. Nevertheless, the marque has had a change of heart and on behalf of the factory, starting next season the Heart of Racing team will run at least one Valkyrie LMH in the WEC (including Le Mans) and at least one in IMSA’s GTP series.

The Valkyrie engine was designed by Cosworth from a clean sheet to suit the Adrian Newey-penned car. It is known as the RA, and was dubbed the RAR in its originally envisaged 2021 LMH guise. In that guise it would have been detuned from the roadcar’s 1000 bhp to about 820 bhp. The 2025 RAR is likely to have to be detuned even further to meet the prevailing LMH homologation requirement.

The RA is a 65º V12 with bore of 98 mm and stroke of 71.8 mm for 6499 cc. It is a linerless production with aluminium block and heads. Its six-pin steel crankshaft runs in seven plain main bearings and is driven by three-ring light alloy pistons through titanium con rods. Gear-driven twin overhead camshafts operate four valves per cylinder at an included angle of 20.4º; the intake valves are 40.6 mm, the exhausts 33.75 mm. The engine is port injected and a distributorless ignition system fires two plugs per cylinder, that twin plug arrangement reflecting the large bore.