The specially prepared 404 convertible broke some 40 records in 1965. Never before had a diesel engine been installed in a 404 convertible. The 404 has been converted to a single-seat to have as little air resistance as possible. The records have been broken with two different engines. On 4 and 5 June 1965 with a 404 1.9 liter diesel Indenor (class E) and from 11 to 14 June 1965 with a 404 2.1 liter diesel Indenor (class D).