What is the firing order on a 1991 Chevrolet vortec 350?
The 1991 Chevrolet 350 (not a Vortec) uses a standard small-block Chevy firing order of 1-8-4-3-6-5-7-2. The Vortec heads didn't appear on the 350 until 1996. A 1991 350 would have the older style heads.