ISI designed and produced turbocharger restrictors for Sports Car Club of America competitors in both Professional Rally and Road Racing disciplines. This was SCCA’s attempt to follow the World Rally Championship WRC rules in limiting horsepower based on competition class and engine displacement. We also made a Go/No-Go test kit for the scrutineering officials to check each turbo car. Restrictors were machined for the following marques: Mitsubishi, Subaru, Mazda and Garrett turbo applications. Needless to say, competitors hated the loss of power!
ISI Turbo Restrictor Turbocharger Restrictors