The Holley LS1/2/6 Ultra Lo-Ram intake manifold kits are designed for GM LS Gen III and IV engines equipped with GM LS1/2/6 (cathedral port) cylinder heads. These intake manifold and rail kits will work with OE or aftermarket cylinder heads.
The 300-604 is the plenum top in the 300-621BK complete kit. Offering this separately allows you to select your components individually as you build your system.
The Ultra Lo-Ram intake manifolds are designed for forced induction (supercharged or turbocharged) engine applications and the 105 mm throttle body part number 112-581 or similar models. The base intake manifold is designed with a lower overall height to fit under a stock or mildly modified hood in the front-feed configuration. The 300-621 Ultra Lo-Ram plenum entry was configured to provide a very low profile modular intake manifold suitable for turbocharged or centrifugally supercharged engines. The fuel rail kits come with two sets of brackets. A set for long (usually standard length) fuel injectors and a set for short (such as Pico, or LS7) fuel injectors.
Features:
- Individual plenum top for 300-621BK allows you to select your components individually as you build your intake system
- Designed for GM LS Gen III and IV engines equipped with GM LS1/2/6 (cathedral port) cylinder heads
- Designed for forced induction (supercharged or turbocharged) engine applications with peak power at 7000-8000 rpm depending on the application
- Modular design allowing the use of the included front plenum entry
- Intake design facilitates custom inlet duct and throttle body placement
- Low height to fit under a stock or mildly modified hood.
- Front entry plenum flange allows design & fabrication of special throttle body adapters or inlet ducts for custom installations
- Clears 1998-2002 (4th Gen) Camaro/Firebird and 1997-2004 (C5) Corvette cowls and hoods without modification
- High volume fuel rails and mounting hardware included with ¾”-16 o-ring ports (8 AN)
About Holley Performance Products
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors powered every Monster Energy NASCAR Cup team and nearly every NHRA Pro-Stock champion for four decades. Now, Holley EFI products power these cars and are dominating the performance world. Holley products for GM's popular LS engine are dominating the LS scene as well. Holley's products also include performance fuel pumps, intake manifolds and engine dress-up products for street performance, race and marine applications. As a single solution or partnered with products from other Holley companies we can give you the edge you need over the competition!
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