Chevy LS Intake Manifold Clearance Issues: What You Need to Know

Installing a serpentine system on a Chevy LS engine is one of the most popular upgrades in the swap and restomod world — and for good reason. March Performance's LS serpentine systems are precision CNC machined from 6061-T6 aircraft-grade aluminum and designed to give your LS swap a clean, show-quality look. But one of the most common fitment questions we get involves intake manifold clearance.

Here's what you need to know before you start the install.

Why Intake Manifold Clearance Is a Common Issue on LS Engines

The LS engine family is used in everything from stock Corvettes to full race builds, and the aftermarket intake manifold options are extensive. The problem is that not all intakes sit at the same height — and some aftermarket high-rise intakes, cathedral port manifolds, or valley covers with raised breather provisions can conflict with accessory brackets that mount near the front of the engine.

Specifically, the alternator bracket on many LS serpentine systems mounts to the passenger side of the block and extends up and over the front of the engine. If your intake manifold is taller than stock, or if it has a prominent front edge, you may have limited clearance between the top of the manifold and the underside of the bracket.

How to Check Before You Install

Before ordering or installing your March Performance LS system, do this quick check:

1. Measure your intake manifold height — from the deck surface of the intake to the highest point at the front of the manifold
2. Check the dimension callouts in the March Performance product photos for your specific kit — we publish clearance dimensions on all LS systems
3. Account for any valley covers or breather adapters — these can add height that isn't immediately obvious

Common Intake Manifolds That May Cause Clearance Issues

• High-rise single plane race intakes
• Certain cathedral port aftermarket manifolds with tall front profiles
• Intakes with raised EGR provisions or front-mount breather bungs
• Some LS3-style intakes on LS1/LS6 blocks due to port height differences

Solutions

Use a low-profile intake. Many LS swap builds run a factory LS3 or LS1 intake which sits at a known height and is fully compatible with March Performance LS systems. If you're building a swap, this is the path of least resistance.

Check for spacer options. In some cases, a small modification to the bracket mounting position or the use of a spacer can resolve clearance issues. Call our tech line at 1.888.729.9070 and we can walk you through options for your specific combination.

Verify before you finalize your build order. If you're running a non-stock intake and you're not sure about clearance, give us a call before you order. We'd rather help you get it right the first time than have you deal with a clearance issue on the bench.

March Performance LS Systems

Our Chevy LS lineup includes all-inclusive serpentine systems, bracket kits, and individual pulleys for LS1, LS2, LS3, LS6, and related engines. Every system is built to our 25-year standard of precision CNC machining, 6061-T6 aluminum construction, and clear powder coat finish — no polishing required. Browse the full LS lineup at marchperformance.com/chevy/chevy-ls/ or call 1.888.729.9070 for tech support.