Designed and calibrated for good street performance and fuel economy in 402 c.i.d. and larger engines with Edelbrock Performer manifolds and other brands of similar design. 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).