Recommended for all engine sizes up to 1600cc for ease of set up. The 30/31 PICT 3 fits both single and dual port manifolds and works well with the 009 distributor with less chance for flat spots. It features a 12 Volt idle shut off solenoid and has a SDVA vacuum port. Its a direct replacement for all 12 Volt 30 PICT single port applications.