How do I know if I need tall valve covers?
In most cases you need tall valve covers only if your valvetrain is upgraded for more clearance—such as high-lift cams or roller rockers—or if your current covers rub against the hood or nearby components.
This article explores what tall valve covers are, when they become necessary, how to verify fit on your specific engine, and practical steps to decide if upgrading is right for you. It covers common scenarios from street builds to performance upgrades and provides actionable checks to avoid buying the wrong part.
What tall valve covers are and what they do
Tall valve covers are simply a taller version of standard valve covers designed to provide extra internal clearance for valvetrain components. They are used when stock covers would otherwise contact tall rocker arms, thick valve springs, or other high-profile components, or when you need additional space for breathers, PCV valves, and related hardware without compromising service access.
Key features of tall valve covers
- Extra height to clear tall valvetrain components (roller rockers, high-lift cams, stud girdles)
- More room for breathers/PCV fittings and gaskets
- Often structually compatible with aftermarket valve-train configurations
Concluding: Tall valve covers are a targeted solution for specific setups where stock covers don’t provide enough clearance or accessibility.
When you should consider tall valve covers
Before deciding, assess whether your current setup may require more clearance or space. The following conditions commonly indicate a potential need for taller covers:
- You installed aftermarket high-lift or aggressive camshafts that push the rocker arms higher than stock.
- You installed roller rocker arms or stud girdles that are taller than stock.
- Your stock valve covers contact the hood or other components during valve-train movement or at operating temperature.
- Your engine uses valve covers with integrated breathers or PCV fittings that require extra space for routing hoses.
- You want easier access to spark plugs or coil packs located near the valve-cover edge.
Concluding: If any of these conditions apply, tall valve covers may be worth considering to restore clearance and servicing ease.
How to verify fit on your engine
Use these steps to check compatibility before purchasing tall valve covers.
- Measure the available clearance between the top edge of the stock valve cover and the underside of the hood or any obstruction at operating temperature.
- Compare this clearance to the total height of the tall valve cover you’re considering, including gaskets and any attached breather/PCV hardware.
- Check for service access: ensure spark plugs, coils, and PCV/breather fittings remain reachable with the tall cover installed.
- If possible, perform a mock-fit or test install on the engine stand or with the hood open to confirm there is no contact with the hood, intake, or headers.
Concluding: careful measurement and a hands-on fit check help prevent buying mismatched parts and ensure you gain the intended clearance.
Engine families and typical scenarios
Some engines are more likely to benefit from tall valve covers due to their valvetrain layout or factory design. Consider these general cues:
- Engines using tall roller rocker arms or high-lift cams, where rocker/valve-train height exceeds stock cover clearance.
- Builds with aftermarket breathers or PCV setups that require extra space for routing and baffling.
- Cars with hood clearance constraints that limit how much room is available above the valve covers.
Concluding: consult your engine builder notes, shop manuals, or community forums for model-specific guidance, as recommendations can vary by engine family and generation.
Summary
Tall valve covers are typically needed when your valvetrain components exceed stock clearance or when hood and accessory layouts create interference. Use precise measurements and a hands-on fit test before buying, and seek model-specific guidance if you’re unsure. With the right fit, tall covers can relieve interference, improve service access, and accommodate advanced valvetrain setups without compromising engine performance.
