Product Description
CNC Fabrication 421005 94.5-03 7.3L Stage 1 Valve Spring Kit
The CNC Fabrication 421005 Stage 1 Valve Spring Kit is a performance upgrade for 1994.5-2003 Ford 7.3L Power Stroke diesel engines designed to provide improved valve control over factory valve springs. Ideal for mild performance builds and engines producing up to approximately 500 horsepower, this kit helps maintain valve stability under increased RPM and boost conditions while retaining excellent drivability and reliability.
Manufactured specifically for the 7.3L Power Stroke platform, the CNC Fabrication Stage 1 Valve Spring Kit delivers increased seat and open pressure compared to stock springs, helping reduce valve float and improve valvetrain control. Whether you're upgrading injectors, tuning, turbochargers, or simply refreshing a high-mileage engine, this kit offers a reliable solution for improved engine performance.
Features
- Designed for 1994.5-2003 Ford 7.3L Power Stroke engines
- Stage 1 performance valve spring upgrade
- Excellent for mild performance and towing applications
- Recommended for engines up to approximately 500 horsepower
- Increased seat pressure over factory valve springs
- Improved valvetrain control at higher RPM levels
- Helps reduce valve float under increased boost and engine load
- Engineered specifically for the Ford Power Stroke platform
- Includes complete set of 16 valve springs
- Manufactured for durability and long service life
Fitment
- 1994.5 Ford F-Series 7.3L Power Stroke
- 1995 Ford F-Series 7.3L Power Stroke
- 1996 Ford F-Series 7.3L Power Stroke
- 1997 Ford F-Series 7.3L Power Stroke
- 1999 Ford Super Duty 7.3L Power Stroke
- 2000 Ford Super Duty 7.3L Power Stroke
- 2001 Ford Super Duty 7.3L Power Stroke
- 2002 Ford Super Duty 7.3L Power Stroke
- 2003 Ford Super Duty 7.3L Power Stroke
Note: This kit does not include valve seals or shims. Verify installed height and valvetrain condition during installation. Professional installation is recommended for best results.
What's Included
- (16) CNC Fabrication Stage 1 Valve Springs
Specifications
- Manufacturer: CNC Fabrication
- Part Number: 421005
- Application: 7.3L Power Stroke Valve Spring Upgrade
- Engine Compatibility: 1994.5-2003 Ford 7.3L Power Stroke
- Stage: Stage 1
- Outside Diameter: 1.354 Inch
- Inside Diameter: 0.940 Inch
- Seat Load: 119 Pounds at 1.800 Inch
- Open Load: 312 Pounds at 1.350 Inch
- Coil Bind Height: 1.280 Inch
- Spring Rate: 458 Pounds Per Inch
- Maximum Recommended Valve Lift: Approximately .510 Inch
- Installed Height: Recommended at 1.800 Inch
- Quantity Per Package: 16 Springs
- Valve Seals Included: No
- Shims Included: No
- Recommended Power Level: Up to Approximately 500 HP
Cross Reference Numbers
421005, CNC421005, 7.3 Stage 1 Valve Springs, 7.3L Valve Spring Kit, Power Stroke Valve Springs, Ford 7.3 Performance Valve Springs
FAQ
What horsepower level is the CNC Fabrication 421005 designed for?
This Stage 1 valve spring kit is typically recommended for mild performance applications and engines producing up to approximately 500 horsepower.
Does this kit include valve seals?
No. The CNC Fabrication 421005 kit does not include valve seals.
Are valve spring shims included?
No. Valve spring shims are not included with this kit.
How many valve springs are included?
The kit includes sixteen valve springs, enough for one complete 7.3L Power Stroke engine.
Why upgrade valve springs on a 7.3L Power Stroke?
Upgraded valve springs help improve valve control, reduce valve float, and maintain valvetrain stability when additional boost, RPM, tuning, or performance modifications are added.
Can these springs be used on a stock engine?
Yes. They can be installed on stock engines as a preventative upgrade or during engine rebuilding and maintenance projects.
