However, AC Delco R45TS or an equivalent from Champion, Autolite, or Bosch were common choices for that era and engine. The "R45TS" is a good starting point for your research.
Before buying, you should:
* Check your owner's manual: This is the best source for the manufacturer's recommended spark plug.
* Look at the existing spark plugs: If you can remove one, the plug's markings will tell you the exact type previously used.
* Consult a parts store: Provide them with the vehicle's year, make, model, and engine details. They can look up the correct spark plug based on your vehicle's information.
Don't rely solely on general information online. Always double-check with your resources mentioned above to ensure you get the correct spark plugs for your specific 1977 Chevy 350. Using the wrong spark plug can damage your engine.
