[Medicone]

From other posts, here are some possible issues/things to try:

1.  Fuel Starvation Issue
a. Check fuel filters (not sure if the 454 has two filters or not, but the 7.4s and 8.1s have a pancake (UFO) shaped filter and a regular fuel filter.  The pancake one is a bit hidden and has a mesh screen.
b.  Clogged Fuel Pickup Tube - Do you have a single tank or duel tanks (e.g., one for each engine)?  If so, maybe clogged pickup tube on tank for starboard engine.  You may want to have the tank cleaned.
c.  Clogged Fuel Vent - unscrew the gas cap to see if that solves the problem - could be a clogged fuel vent limiting the draw of fuel from the tank to the engine.


2.  Electrical/Firing Issue
a.  Check the plugs - make sure plugs are clean.
b.  Check the wires - make sure wires are properly seated on plugs and coils.
c.  Check alternator system - make sure engine batteries have sufficient charge and alternator output is appropriate.

3.  Major Engine Issues
a.  cylinder/valve issues - hire a certified mechanic

My bet, without knowing more, is that it is fuel starvation.

Best of luck,
M1