Here is a concise summary of the text:
**Best Spark Plugs for Your Car's Engine**
* Evolution of spark plugs: Copper (short lifespan, soft) → Platinum (harder, longer-lasting, runs hotter) → Iridium (6x harder than Platinum, 700°F hotter melting point)
* Iridium spark plugs:
+ Last up to 200,000 miles
+ Often used in new engines due to increased difficulty in accessing spark plugs
+ No significant performance or fuel efficiency gains, but offers longer life
* Recommendations:
+ Stick with stock spark plugs for optimal performance
+ If upgrading, only consider Iridium if a compatible version exists, solely for longer lifespan
+ Avoid non-standard, "performance" spark plugs with unproven claims
Here are the extracted key facts, numbered and in short sentences, excluding opinions:
**Spark Plug Facts**
1. Spark plugs fire the air or fuel mixture in a gasoline engine, causing an explosion that pushes the pistons down.
2. Early spark plugs had copper electrodes, a good conductor of electricity.
3. Copper electrodes are extremely soft and wear out relatively quickly.
4. Platinum spark plugs were introduced as an improvement, being much harder than copper.
5. Platinum spark plugs can last up to 100,000 miles.
6. Platinum spark plugs run hotter than copper plugs, burning off deposits more effectively.
7. Iridium spark plugs are six times harder than platinum spark plugs.
8. Iridium spark plugs have a 700-degree hotter melting point than platinum spark plugs.
9. Iridium spark plugs can last up to 200,000 miles or more.
**Engine and Spark Plug Design Facts**
10. Modern engine designs often make spark plugs harder to access.
11. Some engines require significant disassembly to replace spark plugs.
12. Engineers design spark plugs specifically for each engine model.
13. Stock spark plugs are designed to work best with the car's engine.
**Spark Plug Replacement Facts**
14. Using the wrong spark plug size can cause engine damage.
15. Spark plugs must match the exact specifications of the original (e.g., size, thread length, heat range).
16. Upgrading from platinum or copper to an Iridium spark plug (if available and compatible) can provide longer life, but not necessarily better performance.