Single-plane aluminum EFI intake manifold for compatible GM LS1 and LS2 cathedral-port engine applications, including performance builds and LS engine swaps.
Product Highlights
- Fits compatible GM LS1 and LS2 cathedral-port cylinder heads
- Single-plane intake configuration
- Recommended operating range of 3,500–8,000 RPM
- 4150-style square-bore throttle-body flange
- Eight symmetrical intake runners
- Machined injector bosses for multi-port EFI applications
- 1.08 × 2.74-inch port exits
- 6.07-inch manifold height
- Cast-aluminum construction
- Natural aluminum finish
- Machined cylinder-head mating surfaces
- Includes the mounting hardware shown in the product images
Engine Compatibility
| Engine Application |
Compatibility |
Requirements |
| GM LS1 |
Compatible |
Must use compatible cathedral-port cylinder heads and EFI components |
| GM LS2 |
Compatible |
Must use compatible cathedral-port cylinder heads and EFI components |
| LS-swapped vehicles |
Conditional |
Fitment depends on the installed engine, cylinder heads, fuel system, throttle-body arrangement, and available clearance |
Important Fitment Information
This intake manifold is selected according to the engine and cylinder-head configuration. Vehicle year alone does not confirm fitment.
For an LS-swapped Chevrolet C10 or another engine-swap application, confirm the following before ordering:
- The installed engine is a compatible LS1 or LS2 configuration
- The cylinder heads use cathedral-style intake ports
- The throttle body or EFI elbow matches the square-bore mounting flange
- The fuel and injector system matches the intake setup
- The vehicle has sufficient hood and accessory clearance
- The ECU and engine calibration support the completed configuration
This manifold is not compatible with LS3/L92-style rectangular-port cylinder heads.
What This Intake Manifold Does
This manifold replaces the existing intake manifold on a compatible LS1 or LS2 engine.
The single-plane layout uses a central square-bore throttle-body flange and eight intake runners to route air toward the cylinder-head intake ports. Machined injector bosses allow the manifold to be used as part of a multi-port EFI system.
Its 3,500–8,000 RPM operating range is intended for performance-oriented engine combinations that operate at higher engine speeds. The final result depends on the complete engine setup, including the cylinder heads, camshaft, exhaust, fuel system, throttle body, and ECU calibration.
Product Specifications
| Specification |
Value |
| Product type |
EFI intake manifold |
| Engine family |
GM LS |
| Compatible engines |
LS1 and LS2 |
| Cylinder-head port style |
Cathedral port |
| Intake configuration |
Single plane |
| Fuel-injection configuration |
Multi-port EFI |
| Material |
Cast aluminum |
| Finish |
Natural aluminum |
| Recommended RPM range |
3,500–8,000 RPM |
| Throttle-body flange |
4150-style square bore |
| Manifold height |
6.07 inches |
| Port exit dimensions |
1.08 × 2.74 inches |
| Intake runners |
Eight |
| Injector bosses |
Machined |
| SKU |
SPIS08516 |
Construction Details
Single-Plane Layout
The manifold uses a central plenum with eight runners arranged around the square-bore throttle-body opening. This layout is intended for performance applications where airflow at higher engine speeds is a priority.
Machined Injector Bosses
Machined injector bosses are positioned along the cast-aluminum runners for use in a multi-port EFI configuration.
Machined Mating Surfaces
The cylinder-head mounting surfaces include machined intake-port openings, bolt holes, and mounting bosses. These surfaces should be inspected and cleaned before installation.
Aluminum Construction
The manifold is manufactured from cast aluminum and supplied with a natural aluminum finish.
What Is Included
The product images and current listing show:
- 1 × EFI intake manifold
- Mounting bolts
- Washers
- Sealing O-rings
- Threaded fitting or bung
- Mounting hardware shown in the product images
Review the product images before installation and confirm that all illustrated components are present when the package arrives.
Installation Considerations
Professional installation is recommended. Installation instructions are not supplied with the current product.
Before Installation
- Confirm that the cylinder heads use cathedral-style intake ports.
- Inspect the manifold and cylinder-head mating surfaces.
- Confirm the throttle-body or EFI elbow mounting pattern.
- Check the injector and fuel-system arrangement.
- Verify hood, accessory, and firewall clearance.
- Identify the required sensor and vacuum connections.
- Confirm that the ECU and engine calibration match the completed EFI setup.
- Compare all supplied hardware with the product images.
After Installation
- Check the intake sealing surfaces.
- Inspect all fuel connections for leaks.
- Confirm unrestricted throttle movement.
- Check sensor readings.
- Inspect for intake or vacuum leaks.
- Verify engine operation with the correct ECU calibration.
- Reinspect the installation after the first engine heat cycle.
Who This Manifold Is For
This intake manifold may be suitable for:
- GM LS1 performance builds
- GM LS2 performance builds
- LS engine swaps using compatible cathedral-port cylinder heads
- Multi-port EFI conversions
- Higher-RPM engine combinations
- Competition-oriented applications
This intake manifold is not intended for:
- LS3/L92-style rectangular-port cylinder heads
- Buyers looking for a factory-style intake replacement
- Vehicles that have not been converted to a compatible LS engine configuration
- Installations where the engine, cylinder-head type, or available clearance is unknown
Frequently Asked Questions
Does this intake manifold fit an LS1 engine?
Yes. It is intended for compatible GM LS1 engines using cathedral-port cylinder heads. The EFI system, throttle-body arrangement, and available clearance must also match the completed setup.
Does it fit an LS2 engine?
Yes. It is intended for compatible LS2 cathedral-port engine applications. Confirm the cylinder heads, fuel system, throttle-body arrangement, and ECU configuration before installation.
Does it fit LS3 or L92 cylinder heads?
No. LS3/L92-style cylinder heads use rectangular intake ports and are not compatible with this cathedral-port manifold.
Will it fit my Chevrolet C10?
It may fit a C10 that has been converted to a compatible LS1 or LS2 engine. C10 model year alone does not confirm fitment. Check the installed engine, cylinder-head ports, fuel system, throttle-body arrangement, and available clearance.
Is this a direct bolt-on product?
The manifold mounts to compatible cathedral-port cylinder heads. A complete engine-swap or custom EFI installation may require additional work involving the fuel system, throttle body, sensors, wiring, clearance, and ECU calibration.
What is included in the package?
The current product images show the intake manifold, mounting bolts, washers, sealing O-rings, and a threaded fitting or bung. Compare the received components with the product images before beginning installation.
Are installation instructions included?
No installation instructions are supplied with the current product. Professional installation is recommended.
What is the recommended operating range?
The recommended operating range is 3,500–8,000 RPM.
Does the engine require tuning after installation?
The required calibration depends on the complete EFI and engine combination. A custom LS swap or modified engine should be checked by a qualified EFI tuner before regular operation.
PLEASE NOTE!
