454 Timing Issuescontribution.html - That is why you need to disconnect the timing connector, adjust the timing to spec(4 degrees on this aplication), reconnectt he connector and let the ecm take over. I really strongly urge you to go buy a cheap timing light, watch some youtube video's on how to set timing and do it yourself. There are tons of folks here that will help you. Shine the timing light at the harmonic balancer timing mark on the driver's side of the engine. Read the number on the timing plate adjacent to the timing mark on the balancer. The total sounded like a lot but i was not getting any detention. The issue i found was my vacuum advance was connected to. So basically the initial timing of your 454 will depend alot on how much mechanical timing your particular distributor adds.
That is why you need to disconnect the timing connector, adjust the timing to spec(4 degrees on this aplication), reconnectt he connector and let the ecm take over. I really strongly urge you to go buy a cheap timing light, watch some youtube video's on how to set timing and do it yourself. There are tons of folks here that will help you. Shine the timing light at the harmonic balancer timing mark on the driver's side of the engine. Read the number on the timing plate adjacent to the timing mark on the balancer.