What are the piston numbers on a 1985 Chevy 305?
The firing order for a 1985 Chevy 305 small-block V8 is 1-8-4-3-6-5-7-2. This dictates the piston number sequence as the engine cycles. There isn't a visual "number 1" stamped on the piston itself. The number 1 piston is determined by its position relative to the timing cover and its firing order position in the sequence above.