In the 1980’s Finland developed their own class of racing based on Super Vee, it allowed for a lighter chassis powered by 1600cc engine and was called Formula VW 1600. When VW stopped supporting the category it was renamed Formula 4 and the 1800cc engine from the VW Golf was introduced. As the class became popular many second-hand F3 cars, especially Ralts and Reynards, were converted to F4 specification as the two classes were very similar in performance.
Finland’s own Seppo Nieminen began to manufacturer the Niemax for F4 , the chassis was built around Veemax components and in 1986 the Niemax began racing in the Finnish F3 Open Championship The design proved successful with Sami Pensala winning the F4 championship in 1987 and 1988.
Although the Niemax never raced in F3 specification, it did race in a F3 championship and I have included it in order to explain how it differed from the contemporary F3 regulations.
Thanks to Antti Rinne for additional information.