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Plenum Top for 300-621BK Modular Ultra Lo-Ram Intake Bases [Black Finish]
Product Discontinued
HOLLEYPART NUMBER: 510-300-604BK

Plenum Top for 300-621BK Modular Ultra Lo-Ram Intake Bases [Black Finish]

Currently Unavailable

This product is no longer available. Please call customer service for assistance at 1-800-345-4545.

Intake Manifold Tops [Lids]
Modular Ultra Lo-Ram EFI Intake Manifold Plenum Top
  • For Holley 300-621BK
  • GM LS1/LS2/LS6
  • Black Powder-Coat Finish
  • Sold Individually

    Breakdown of Included Items

    Holley 300-604BK Features:

    • Plenum top for Holley Modular Ultra Lo-Ram EFI Intake Manifold 300-621BK
    • Designed for GM LS Gen III and IV engines equipped with GM LS1/LS2/LS6 cathedral port cylinder heads
    • Bolt-through design
    • Non-burst panel
    • Black powder-coat finish

    Note: Plenum top casting can be machined for a 6 1/8 in. x 3 1/8 in. burst panel

    Emissions Note:

    This part is only legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles or on vehicles used solely for the purposes of closed competition racing.

    CLICK THIS LINK FOR IMPORTANT CARB & EPA EMISSIONS INFORMATION ABOUT THIS PART

      • Components for GM LS/LT Lo-Ram and Ultra-Lo Ram Intakes

      These components are specifically for Holley's Lo-Ram and Ultra-Lo Ram line of intake manifolds. You can select the parts individually as you build your injection system or when replacing damaged parts.

    Part TypeIntake Manifold Cover
    Product LineHolley GM LS/LT Lo-Ram and Ultra Lo-Ram Intake Manifold Components
    BrandHOLLEY
    Package Height1.97
    Package Width10.23
    Package Length18.7
    Weight4.45 PG
    Part CategoryPerformance Parts
    Cover FinishBlack
    Cover Plate MaterialAluminum
    QuantitySold individually
    Mounting Hardware IncludedYes
    Package Qty1
    Package TypeEA
    No Questions
    No Reviews

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