* 4.1L V8 (HT4100): 1-8-4-3-6-5-7-2
* 4.5L V8 (HT4500): 1-8-4-3-6-5-7-2
Note that both engine options in the 1985 DeVille use the same firing order. It's important to know which engine is in *your* specific car to be absolutely certain. You can check your vehicle's identification number (VIN) or the engine block itself for the engine code.
