What is valve float and why should I prevent it?

Valve float occurs when the valve springs can't close the valves fast enough at high engine speeds. This can cause the camshaft to hit the open valve, leading to bent valves, piston damage, and other serious engine problems. These Manley springs are designed to prevent this.

Do these valve springs come with retainers or locks?

This part number (221434-32) includes 32 valve springs. Retainers, locks, and seals are typically sold separately and should be inspected or replaced during a valvetrain rebuild.

Are these springs suitable for stock camshafts?

These NexTek Series springs are designed for performance applications and are often used with upgraded camshafts. While they can be used with stock camshafts, they are particularly beneficial when paired with performance cams that require higher spring pressures for proper operation.

Manley Ford 4.6L/5.4L DOHC NexTek Series High Performance Valve Springs (4 valves per cylinder)

Specifications

Brand: Manley Performance
Part #: 221434-32
UPC: 807298023465

Manley Ford 4.6L/5.4L DOHC NexTek Series High Performance Valve Springs (4 valves per cylinder)

Name: Manley Ford 4.6L/5.4L DOHC NexTek Series High Performance Valve Springs (4 valves per cylinder)
Brand: Manley Performance
Price: 734.22 USD
Availability: InStock

$734.22

On Backorder

Order now to reserve yours — we'll ship as soon as stock arrives. Full refund if we're unable to fulfill.

Fits 1999-2008 Ford Mustang. Manley NexTek Series high performance valve springs for DOHC 4.6L/5.4L engines. Essential for high-RPM operation.

Key Features

Fits 1999-2001 and 2007-2008 Ford Mustang, 2005-2006 Ford GT.
Designed for 4.6L and 5.4L DOHC Ford modular engines with 4 valves per cylinder.
Manley NexTek Series valve springs are built for high-RPM performance.
Ensures reliable valve closure and helps prevent valve float.
Includes 32 springs, sufficient for all valves in a DOHC engine.
A well-built component for engine rebuilds and performance upgrades.

⚠️ CA WARNING: This product can expose you to chemicals known to the State of California to cause cancer and/or birth defects or other reproductive harm. Learn more

Secure CheckoutFast Shipping631-982-0042

Fits these vehicles

Ford GT 2005-2006
Ford Mustang 1999-2001, 2007-2008

Product Details

If you're rebuilding the top end of your 1999-2008 Ford Mustang with a 4.6L or 5.4L DOHC engine, especially if you're planning on higher RPMs or more aggressive camshafts, a strong set of valve springs is crucial. These Manley NexTek Series valve springs are built to handle the demands of performance applications, ensuring your valves close reliably and prevent issues like valve float, which can lead to serious engine damage.

Manley has a solid reputation for making well-built engine components, and this NexTek Series set is no exception. They are designed to work with 4 valves per cylinder setups, common in these Ford modular engines. The springs are made from high-strength materials and are tested to ensure they can maintain consistent pressure across a wide range of engine speeds. This means better valve control and improved performance when you push your engine hard. They are a direct replacement for your stock springs, making installation straightforward for a qualified mechanic.

This set includes 32 springs, enough for all 32 valves in your DOHC engine (4 valves per cylinder x 8 cylinders). When upgrading your valvetrain, it's always a good idea to inspect your retainers and valve seals as well to ensure everything is in top condition. These springs are a key component for anyone looking to get the most out of their performance Mustang engine.