HLY300-121BK - Holley EFi Gen III LS1,LS2,LS6 2X4 Dual Plane Mid Rise Intake Manifold, Duel Rails Included - Fits all Gen III Heads With Cathedral Ports, Black Ceramic Coated

This product may require vehicle validation(s) for proper fitment. Please contact us to confirm correct vehicle fitment and usage.

Availability: Special Order Item
Pricing: $466.95


•The Holley GM LS1/LS2/LS6 2x4V dual-plane was designed in the tradition of the great dual Holley 4160 induction systems that competed on drag strips, in Trans-Am and at Lemans in the 1960’s. The technology of the LS pushrod engine is now mated with the impressive multi-carb looks and performance of the muscle-car era!

•The dual-plane equal-distribution layout produces great mid-range torque without compromising top end power. The LS engine architecture does not utilize an intake mounted water neck or \distributor so it’s perfect for two Holley carburetors and this intake manifold design takes full advantage of that opportunity.
•Carbureted and EFI versions available
•Power band from 1500-7000 rpm
•Appropriate for any street/performance, muscle car, or street rod enthusiast
•Cast aluminum construction
•Intended for use on all GM LS Gen III engines equipped with LS1/LS2 style cathedral port cylinder heads

Installation Notes
All GM LS Gen 3 engines equipped with LS1/LS2 style cathedral port cylinder heads

Click on documents tab for instructions


  • 300-121BK
  • 300-121BK
  • 090127715857
  • Holley Performance
  • Special Order Item
  • New

Shipping Information

  • Item Requires Shipping
  • 25.0 lbs.
  • W14.5000” x H10.0000” x L20.5000”

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