How to Set the Ignition Timing in a 351C
- 1). Start your 1971 Ford Mustang, or any other Ford vehicle with a 351C. Turn all car accessories off.
- 2). Put your transmission in neutral and engage the emergency brake. Bring the engine to an idle speed of 700 rpm if you have a manual transmission, or 600 rpm if you have an automatic. Engage the idle speed solenoid.
- 3). Connect the timing light and/or tachometer to your 351C engine's battery, No. 1 spark plug and the main crank pulley.
- 4). Check where the timing mark on the pulley falls compared to the standard 6 degrees BTDC it should be. You don't have to change the ignition timing if it already reads 6 degrees BTDC.
- 5). Loosen the distributor lockdown bolt with your wrench. The lockdown bolt should be located by the base of the distributor housing.
- 6). Disconnect and plug the distributor vacuum hose into the distributor housing.
- 7). Rotate the distributor by hand until the timing mark drifts into 6 degrees BTDC.
- 8). Tighten the distributor lockdown bolt with your wrench once you have set the timing to 6 BTDC. Unplug and connect the distributor vacuum hose. Remove the timing light and/or tachometer.
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