Edelbrock Performer Non-EGR Carb is designed and calibrated for optimum street performance in small-block and big-block engines with Performer RPM, RPM Air-Gap and Torker II manifolds and with Performer manifolds on large cubic-inch engines. Includes both timed and full vacuum ports for ignition advance. Electric choke #1478 can be added if needed. Comes with: Metering Jets - Primary .113, Secondary .107; Metering Rods - .071 x .047; Step-Up Spring - orange (5" Hg). Use our Carb Stud Kits EDL-8008 or EDL-8024 if needed