Engine Valve System Specifications
WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2003 GMC Yukon XL, 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Suburban, and 2003 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.
VALVE SYSTEM
| Application | Specification | |
|---|---|---|
| Lifter | Hydraulic, Roller Followers | |
| Rocker Arm Ratio | 1.70:1 | |
| Valve Lash - Exhaust & Intake | Net Lash | |
| Face Angle (Intake/Exhaust) | 45 Degrees | |
| Seat Angle (Intake/Exhaust) | 46 Degrees | |
| Seat Runout (Intake/Exhaust) | 0.002" (0.0500 mm) | |
| Seat Width | ||
| Intake | 0.030-0.060" (0.800-1.200 mm) | |
| Exhaust | 0.060-0.095" (1.651-2.159 mm) | |
| Stem Clearance - Production | ||
| Intake | 0.0010-0.0029" (0.025-0.074 mm) | |
| Exhaust | 0.0012-0.0031" (0.030-0.079 mm) | |
| Stem Clearance - Service | ||
| Intake | 0.0010-0.0034" (0.025-0.088 mm) | |
| Exhaust | 0.0012-0.0036" (0.030-0.091 mm) | |
| Valve Spring Pressure | ||
| Closed | 86-94 lbs. @ 1.808 (381-419 N @ 33.985) | |
| Open | 216-236 lbs. @ 1.338 (962-1058 N @ 33.985) | |
| Valve Spring Installed Height | 1.808-1.838" (45.923-46.685 mm) | |
| Valve Spring Free Length | 2.218" (56.35 mm) | |
| Valve Head Diameter | ||
| Intake | 2.19" (55.63 mm) | |
| Exhaust | 1.72" (43.69 mm) | |
| Valve Stem Diameter | ||
| Intake | 0.3715-0.3722" (9.436-9.454 mm) | |
| Exhaust | 0.3713-0.3720" (9.431-9.449 mm) | |
| Maximum Valve Spring Installed Height Shim (Service Only) | 0.030" (0.726 mm) | |
| Maximum Valve Spring Tension Shim (Service Only) | 0.030" (0.726 mm) | |
| Maximum Combined Valve Spring Installed Height & Valve Spring Tension Shim (Service Only - Shim Placed Under Valve Rotator Only) | 0.060" (1.524 mm) | |