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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 manifolds will work with OE or aftermarket cylinder heads. 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. The 300-621 Ultra Lo-Ram front-feed 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:
- 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.
- With forced-induction and the short runner length the engine rpm at which peak power occurs is more likely to be coupled to the supercharger or turbocharger being used
- Modular design allowing the use of front-feed 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 4th Gen Camaro and C5 Corvette cowls and hoods without modification
- High volume fuel rails and mounting hardware included with ¾”-16 o-ring ports (8 AN)
| Basic Operating RPM Range | 3500-8000 RPM |
|---|---|
| Brand | Holley EFI |
| Category | Intake Manifolds |
| Color | Black |
| Construction | Cast |
| EGR Port | No |
| Emission Code | 3 |
| Engine | GM LS1/LS2/LS6 |
| Finish | Black |
| Flange Style | EFI |
| Front Height | 6.86" height with throttle body adapter |
| Front Maximum Height | 6.86 IN |
| Fuel Injectors Included | No |
| Fuel Rail(s) Included | Yes |
| Fuel System Type | EFI |
| Gasket Or Seal Included | No |
| Grade Type | Performance |
| Injector Quantity | Single |
| Inlet Location | Front |
| Intake Port Gasket(s) Included | No |
| Manifold Type | Ultra Lo-Ram |
| Material | Aluminum |
| Nitrous Bung(s) Included | No |
| Plenum Finish | Black |
| Product Type | Intake Manifold |
| Recommended Use | Forced Induction |
| Removable Runners | No |
| RPM Power Band | 3500-8000 RPM |
| Single Or Dual Plane Type | Single Plane |
| Throttle Body Bore Diameter | 105 MM |
| Throttle Body Included | No |
| Warranty | Limited 90 Day |
| UPC | 090127079676 |
| Part Number | 300-621BK |
Emissions
3
This part is legal for sale and use on Uncontrolled (Non-Emissions Controlled) Vehicles.
The following vehicles are considered Uncontrolled (Non-Emissions Controlled) Vehicles:
- 1965 and older U.S. manufactured California Certified vehicles
- 1967 and older U.S. manufactured Federally Certified vehicles
- 1967 and older Foreign manufactured vehicle
WARNING: It is against the law to install this part on an Emissions Controlled Vehicle
The following vehicles are considered Emissions Controlled Vehicles:
- 1966 and newer U.S. manufactured California Certified vehicles
- 1968 and newer U.S. manufactured Federally Certified vehicles
- 1968 and newer Foreign manufactured vehicle
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