Japanese manufacturers Subaru and Mitsubishi are both developing high performance versions of their existing Group N cars to enable them to compete on level terms with their Super 2000 rivals next year.
Work on the cars, based on the firms Impreza and Lancer models, began earlier this month after the FIA World Motor Sport Council gave the green light to a new ‘R4’specification.
An R4 kit, homologated by the current Group N manufacturers, should enhance the performance of the two-litre turbo cars, bringing them in line with the normally aspirated Super 2000s.
The R4 class could lead to Imprezas and Lancers competing alongside Super 2000 cars in the 2011 SWRC, and should also give the turbo cars a boost in national rallies where they already compete in the same category as the S2000s.
Details of the kit are yet to be finalised by the FIA, but next year’s R4s are expected to be stronger and lighter than the existing N4 models, with longer suspension travel and modifications to steering columns, dashboards and windows. Further power could be unlocked by widening the mandatory 33mm turbo restrictor.
Production car World Rally Champion Armindo Araujo gave a glimpse of the R4s potential when he drove a Mitsubishi Lancer Evo X R4 prototype at last week’s Monza Rally Show in Italy. His times were consistently in the top two or three of the S2000 class and he rounded off the event by beating all the S2000 cars to win the final stage of the event.