* Engine modifications: A stock engine will have different needs than one with performance upgrades (camshaft, higher compression, etc.).
* Fuel type: The octane rating of your fuel influences the heat range needed.
* Driving style: Aggressive driving generates more heat than casual driving.
* Climate: Hot climates require different heat ranges than cold climates.
However, some popular and generally well-regarded choices for a Chevy 350 include:
* ACDelco 41-985 (or equivalent): This is often considered a good starting point for a stock or mildly modified 350. It's a reliable and readily available option. Check the ACDelco website for the correct part number based on your specific engine and application.
* NGK TR55 or TR6: NGK plugs are another popular choice, known for their quality and performance. The TR55 and TR6 are common heat ranges used in Chevy 350s, but again, the correct heat range depends on your specific setup.
* Champion RC12YC: A more budget-friendly option, Champions are still a viable choice for many applications.
Crucially, you should consult your engine's specifications and owner's manual. This will often recommend a specific heat range and plug type. Failing to use the correct heat range can lead to pre-ignition (detonation), fouling, or overheating.
If you have performance modifications, you'll likely need a colder heat range plug. If unsure, consulting a mechanic or a reputable parts store is highly recommended. They can help you determine the appropriate spark plug for your specific application. Don't be afraid to provide them with details about your engine modifications and driving conditions.
