Product Description
CNC Fabrication 421008 94.5-03 7.3L Stage 1 Valve Spring Kit With Valve Seals and Shims
The CNC Fabrication 421008 Stage 1 Valve Spring Kit is a proven upgrade for 1994.5-2003 Ford 7.3L Power Stroke engines looking for improved valvetrain control and reliability. Designed as a mild performance upgrade over factory valve springs, this kit is ideal for street-driven, towing, and performance applications producing up to approximately 500 horsepower.
Engineered specifically for the 7.3L Power Stroke platform, the CNC Fabrication Stage 1 Valve Spring Kit includes sixteen valve springs, valve seals, and shims to help maintain proper valve control under increased RPM and boost conditions. Whether you're rebuilding a cylinder head or upgrading your valvetrain while performing other engine modifications, this kit provides improved spring pressure and durability over worn factory components.
CNC Fabrication is dedicated exclusively to the Ford Power Stroke platform, delivering products designed to exceed expectations while providing industry-leading technical support and expertise.
Features
- Designed for 1994.5-2003 Ford 7.3L Power Stroke engines
- Stage 1 performance valve spring upgrade
- Excellent upgrade for stock and mild performance builds
- Recommended for applications up to approximately 500 horsepower
- Improved valve control over factory springs
- Helps reduce valve float at higher RPM levels
- Includes valve seals and shims
- Ideal during cylinder head service or engine rebuilds
- Designed specifically for Ford Power Stroke applications
- Manufactured to deliver reliable long-term performance
Fitment
- 1994.5 Ford 7.3L Power Stroke
- 1995 Ford 7.3L Power Stroke
- 1996 Ford 7.3L Power Stroke
- 1997 Ford 7.3L Power Stroke
- 1998 Ford 7.3L Power Stroke
- 1999 Ford 7.3L Power Stroke
- 2000 Ford 7.3L Power Stroke
- 2001 Ford 7.3L Power Stroke
- 2002 Ford 7.3L Power Stroke
- 2003 Ford 7.3L Power Stroke
Note: Recommended for stock and mild performance applications. Always verify installed height, valve lift, retainer compatibility, and overall valvetrain condition during installation.
What's Included
- (16) CNC Fabrication Stage 1 Valve Springs
- (16) Valve Seals
- Valve Spring Shims
Specifications
- Manufacturer: CNC Fabrication
- Part Number: 421008
- Application: 1994.5-2003 Ford 7.3L Power Stroke
- Product Type: Stage 1 Valve Spring Kit
- Outside Diameter: 1.354 Inch
- Inside Diameter: 0.940 Inch
- Seat Load: 119 lbs @ 1.800 Inch
- Open Load: 312 lbs @ 1.350 Inch
- Spring Rate: 458 lbs/In
- Coil Bind Height: 1.280 Inch
- Maximum Recommended Valve Lift: Approximately .510 Inch
- Installed Height: Recommended Height Per Manufacturer Specifications
- Quantity: 16 Springs Per Kit
- Includes: Valve Seals and Shims
- Recommended Power Level: Up to Approximately 500 Horsepower
Cross Reference Numbers
421008, CNC421008, 7.3 Valve Spring Kit, 7.3 Stage 1 Valve Springs, Power Stroke Valve Springs, 7.3 Cylinder Head Valve Spring Upgrade
FAQ
What horsepower level is the CNC Fabrication 421008 designed for?
This Stage 1 valve spring kit is commonly recommended for stock and mild performance applications producing up to approximately 500 horsepower.
Why upgrade valve springs on a 7.3L Power Stroke?
Upgraded valve springs help maintain valve control at higher RPM levels, reduce the risk of valve float, and improve overall valvetrain stability in performance applications.
Does this kit include valve seals?
Yes. The CNC Fabrication 421008 kit includes valve seals and shims along with the valve springs.
How many springs are included?
The kit includes sixteen valve springs, providing a complete set for one 7.3L Power Stroke engine.
Can these springs be used with aftermarket camshafts?
These springs are designed primarily for stock and mild performance applications. Always verify spring pressure, installed height, and valve lift requirements when using aftermarket camshafts.
Is this a good upgrade during a cylinder head rebuild?
Yes. Many builders choose to upgrade valve springs while servicing cylinder heads to improve reliability and future performance capability.
