Opel Manta 400 Rally Homologation
The Opel Manta 400, produced from 1981 to 1984 in a limited run of just 245 units, was Opel's entry into the ultra-competitive Group B rally championship. Named for the 400 units originally planned for homologation (though only 245 were ultimately built before rules were satisfied), the Manta 400 transformed the popular Manta B coupe from a stylish but modest sports car into a genuine competition machine.
The key to the Manta 400's competition credentials was its engine. Where the standard Manta used overhead-valve or single-cam engines, the 400 received a completely new twin-cam 16-valve cylinder head designed by Cosworth — the same engineering firm responsible for the DFV Formula 1 engine. This head was fitted to a 2.4-liter bottom end, producing 144 horsepower in road-legal form. In competition specification, with larger turbocharger (on later rally cars), revised fueling, and exhaust modifications, the engine could produce well over 300 horsepower.
The body received modifications appropriate to its competition purpose. Glass-fiber front fenders, hood, and rear panel reduced weight significantly compared to the steel components of the standard Manta. A large front air dam, extended wheel arches, and a boot-mounted rear spoiler improved aerodynamics and accommodated wider wheels and tires. The interior was stripped of unnecessary equipment, with lightweight Recaro seats and a competition instrument panel replacing the standard items.
In rally competition, the Manta 400 competed against the Group B titans — the Audi quattro, Lancia Rally 037 and Delta S4, and Peugeot 205 T16. While it could not match the all-wheel-drive cars in wet or slippery conditions, its rear-wheel-drive layout and excellent weight balance made it a formidable contender on tarmac rallies. Guy Frequelin and Henri Toivonen both achieved notable results in the Manta 400, and the car won several national championship events.
The road-going Manta 400s were distinctive machines. The Cosworth-headed engine gave the car a sporting character far beyond the standard Manta, with a willingness to rev and a mechanical quality that standard Opel engines couldn't approach. The lightweight body and uprated suspension provided handling that was sharp and responsive, if somewhat demanding due to the live rear axle's limitations.
Only 245 road cars were built before production ended, making the Manta 400 one of the rarest Opels in existence. Today, it is the most valuable production Opel ever made, sought after by collectors who appreciate its competition heritage, its Cosworth engineering pedigree, and its role in one of motorsport's most dramatic eras.
With only 245 examples, verify authenticity through Opel Classic archives and the Manta 400 registry. The Cosworth twin-cam head requires specialist knowledge to maintain — parts are extremely scarce. Check the glass-fiber body panels for damage, repairs, and correct specification. The live rear axle with Watts linkage is robust but check for bushing wear and axle casing leaks. Verify the correct Getrag gearbox is fitted. Many Manta 400s were used in competition — check for crash damage repairs and verify the chassis plate. A complete, unmodified road-specification car is more valuable than a competition-modified example for most collectors.
245 road-going Manta 400s were produced for Group B homologation between 1981 and 1984. The twin-cam 16-valve head was designed and manufactured by Cosworth Engineering. Road cars produced 144 hp; competition cars with turbocharger could exceed 300 hp. The car competed in the World Rally Championship from 1983 to 1986. Bodies included glass-fiber front panels for weight reduction.