Delco EST 4 Cylinder Spark Plug Wire Set | Volvo 3888324 OEM 7mm ignition set for Volvo Penta GM 3.0L marine engines with Delco EST distributors. Delco EST marine spark plug wire set Fits Volvo Penta 3.0L 4 cylinder engines with Delco EST ignition systems Original Volvo Penta Replaces Volvo Penta 3851815 Replaces Mercury 84-816761Q14 Replaces Marine Power 470300 Replaces OMC/BRP 503749