Projected square platinum electrode spark plug — Why it’s better

Why carmakers use projected square platinum electrode spark plugs

A Projected square platinum electrode spark plug is built like a double fine wire spark plug except for the ground electrode. The ground electrode has a shorter reach and has a fused square shaped tip of platinum. They’re used in turbocharged engine applications where the car maker requires a “high ignitability” spark plug. They incorporate a platinum square ground electrode placed directly over the center electrode to provide a more focused spark and improved heat dissipation.

Advantages of a PSPE spark plug

This unique ground electrode shape focuses the spark between the fine-wire center electrode and platinum ground piece that extends past the side electrode strap. Because the side electrode and center electrodes are smaller, they require lower voltage to jump the gap.

This reduces misfires and increases power. The smaller mass of both the center and side electrodes reduce quenching over traditional nickel center electrodes and conventional side strap electrodes.

Spark plug manufacturers use either platinum or iridium for the precious metal tips.

WARNING: Never use a “coin gap gauge” when checking the gap on a double fine wire spark plug. The wedge can break off the fine wire electrode. Always use a wire style gauge to check or adjust the gap.

Projected Square Platinum Electrode is registered to NGK

©, 2022 Rick Muscoplat