The Buckshot Racing Super Sport (SS-77) Switchbox Set is a German-made replacement ignition package for Mercury Marine and Mercury Racing V6 two-stroke outboards using the classic 332-7778-series ADI/CDI ignition system. It fits many 2.0L, 2.4L, and 2.5L Mercury V6 engines produced from 1976 through 1999.
Each V6 uses two (2) switchboxes, so the Buckshot Racing #77 package is supplied as a matched pair. The two modules are electrically linked through the white/black bias circuit, making matched switchboxes important for consistent ignition timing and reliable operation across all six cylinders.
German-Made Super Sport Construction
The 338-7778-77 Super Sport switchboxes are manufactured in Germany by PRÜFREX, a long-established manufacturer of ignition and engine-control electronics.
These switchboxes use U.S.-style SAE terminal posts with brass nuts and include the required ground straps and threaded hardware. They are designed as a premium replacement for aging Mercury 7778-series modules in both recreational and high-performance applications.
These may be among the last available production runs of this German-made version, making complete matched sets increasingly difficult to source.
Mercury 332-7778 Cross References
The Buckshot Racing #77 338-7778 (SS-77) replaces Mercury 332-7778A6, 332-7778A12, 332-7778A13, and 332-7778A14, as well as earlier numbers in the same ignition family.
Common cross-references include 114-7778, Sierra 18-5775, 5524A1, 338-7778A1, 7778A3, 7778A6, 7778A7, 7778A9, 7778A12, 7778A13, F7778A9, and F749301.
Mercury Marine & Mercury Racing Applications
The 332-7778 switchbox family was used across many Mercury V6 two-strokes, including 135, 150, 175 and 200 HP Black Max, XR2, XR4, XR6, Magnum, Laser EFI and XRi, along with many 2.0 Liter, 2.4 Liters, 2.5 Liters, 260 EFI, 245 Carb, and Pro Max 150, 200, 225 HP applications.
It is also used on numerous Mercury Racing engines with conventional ADI ignition systems, including various 2.4L Bridgeport, 245 Carb, 260 EFI, S3000 and 300 Drag-style configurations. Exact fitment should be confirmed by the existing switchbox number and ignition layout, particularly on modified race engines.
How the Mercury Switchbox Works
The switchbox is the electronic switching section of Mercury’s Alternator Driven Ignition, or ADI/CDI system. The stator supplies charging voltage while the trigger sends crankshaft-position signals. Each switchbox stores and releases that energy at the correct moment to fire three ignition coils.
On a Mercury V6, one switchbox controls cylinders 1-3-5 and the other controls 2-4-6. A failing switchbox can therefore cause loss of spark on all three cylinders of one bank or ignition group.
However, a three-cylinder no-spark condition does not automatically mean the switchbox has failed. A stator circuit, trigger, wiring fault or kill circuit can produce similar symptoms, so proper DVA testing should be performed before replacing parts.
Why We Supply Two Switchboxes
The two Mercury V6 switchboxes share a white/black bias circuit that helps control ignition timing. A fault in one module can influence the other and create misleading ignition symptoms.
Installing a matched pair of 338-7778-77 Super Sport switchboxes gives the complete six-cylinder ignition system consistent electronics and eliminates uncertainty caused by mixing old and new modules with different electrical characteristics.
The Buckshot Racing #77 German-Made 338-7778-77 Super Sport Switchbox Set includes two matched modules, SAE brass terminal nuts, ground straps and mounting hardware for classic Mercury 2.0L, 2.4L and 2.5L V6 two-strokes.
For Black Max, XR, XRi, EFI, Pro Max and Mercury Racing engines still using the proven 332-7778 ignition system, this set provides a high-quality replacement for aging factory switchboxes.
Contact Mike Hill with technical questions at 714-697-1716