Ignition Timing
Ignition timing is checked or adjusted with engine at normal operating temperature, distributor vacuum line disconnected and plugged, transmission in Neutral and engine at normal idle. On "P" models, use number two cylinder and timing mark tab on bottom of cylinder.
Ignition Timing Specifications
| Application | Man. Trans. | Auto. Trans. | |||
|---|---|---|---|---|---|
| 350" 2-Bbl. | 0°TDC | 8°BTDC | |||
| 350" 4-Bbl. Fed. Light Duty | |||||
| Suburban | 6°BTDC | 12°BTDC | |||
| G-2500, 3500 Rally | 8°BTDC | 12°BTDC | |||
| All Others | 8°BTDC | 8°BTDC | |||
| 350" 4-Bbl. Cal. Light Duty | |||||
| Suburban | 4°BTDC | 6°BTDC | |||
| All Others | 4°BTDC | 8°BTDC | |||
| 350" Heavy Duty, All | 4°BTDC | 4°BTDC | |||
| 454" Light Duty, All | (1) | 10°BTDC | |||
| 454" Heavy Duty, All | 8°BTDC | 8°BTDC | |||
|
|||||