Omc 5.7 ignition timing

[Nick2020]

I just put a 350 Chevy engine in my boat that came from a car. I put all the parts from the old motor on. I am having issues with backfiring through the carb, so I messed with ignition timing and noticed that it actually runs a lot better with timing way before TDC. What could be causing this?

 

[Bondo]

I just put a 350 Chevy engine in my boat that came from a car. I put all the parts from the old motor on. I am having issues with backfiring through the carb, so I messed with ignition timing and noticed that it actually runs a lot better with timing way before TDC. What could be causing this?

Ayuh,..... That usually means it's runnin' Lean,.....

Put the timin' back where it belongs, or you'll have holes in the pistons,.....
Both a lean condition, 'n/ or advanced timin' will induce detonation, 'n hole the pistons,....

 

[jerryjerry05]

The car carb is probably sucking air someplace.
Start it and spray starting fluid around the base.
If the spray makes it run different? then it's sucking air.

 

[Sattech200]

You did switch cams also right?