Edelbrock Performer Non-EGR Carb is designed for 402 c.i.d. and larger engines with Edelbrock Performer manifolds and other brands of similar design, these carbs are recommended only for stock to Performer level applications. They are not recommended for use on RPM or Torker II intake manifolds. Calibrated 2% leaner than #1407. Provides excellent fuel economy when used on 454 c.i.d. Chevy and 460 c.i.d. Ford with Performer manifold. Includes both timed and full vacuum ports for ignition advance. Comes with: Metering Jets - Primary .110, Secondary .107; Metering Rods - .075 x .047; Step-Up Spring - orange (5" Hg). Use our Carb Stud Kits EDL-8008 or EDL-8024 if needed