Indmar Marine Spark Plug – Supercharged 575 | Part #597128 Purpose-built for the most powerful engine in the Indmar lineup — this genuine spark plug is the only correct choice for the Supercharged 575 marine engine. The SC 575 operates at significantly higher cylinder pressures and temperatures than any naturally aspirated Indmar engine — demanding a spark plug engineered specifically to handle the extreme conditions of forced induction marine performance. Compatible with: Indmar Supercharged 575 marine engines fitted to Malibu, Moomba, Supra, and Tige boats. Contact us to verify fitment for your specific model year before ordering. ⚠️ IMPORTANT — Correct Plug for Supercharged 575 Only: THIS PLUG IS SPECIFICALLY FOR SUPERCHARGED 575 MODELS ONLY. If your boat is fitted with the naturally aspirated Ford 6.2L engine you must use: 597037-16 – Spark Plug Ford 6.2L CYFS-12FP Set of 16 If you are unsure which engine your boat is fitted with — contact us before ordering.