The firing order of the 302 is 1-5-4-2-6-3-7-8. However, you do not adjust valves based on firing order. A common and logical approach is to work your way around the engine, cylinder by cylinder, adjusting the intake and exhaust valves for each one before proceeding. For example:
1. Cylinder 1: Adjust intake, then exhaust.
2. Cylinder 2: Adjust intake, then exhaust.
3. Cylinder 3: Adjust intake, then exhaust.
4. Cylinder 4: Adjust intake, then exhaust.
5. Cylinder 5: Adjust intake, then exhaust.
6. Cylinder 6: Adjust intake, then exhaust.
7. Cylinder 7: Adjust intake, then exhaust.
8. Cylinder 8: Adjust intake, then exhaust.
Remember to consult your specific Ford 302 engine's service manual for the correct valve lash specifications (clearance) for both intake and exhaust valves. The manual will also provide detailed instructions and diagrams for the process. This is crucial to avoid damaging the engine.