285 HP AND UP (Price Includes 8 Plugs) Carbureted Plug gap .035, EFI (GT40) and Pro Tec Ignitions gap at .045. NOTE: The Autolite #764 has been superseded by Autolite #104. The threads are longer, don't worry!
GM Vortec 300+ HP (Rep. MR43LTS) Includes 8. The Vortec engines have the intake manifold bolts installed going straight down, non Vortec bolts are angled. PLUG GAP .045. BUT, IF USING WITH HVS IGNITION, .060 IS RECOMMENDED.
* Most Indmar EFI and carbureted after 1993.
* Not for coil pack type ignitions like LT1
* PCM GM EFI engines up to 2001
* Indmar Pt #556083
* Indmar thru 2005 (Monsoon, MCX, RTP)
2 screws hold down the cap with a rectangular cut out at the base for the igniton module wires.
AROUND 2002 UP MERCRUISER #47-862232A2, Black Scorpion S/N OM391600 and up, S/N OW690000 and up. MX 6.2L S/N OM317000 and up. 5.7 MPI SKI S/N 1A090000 and up. New style pump that has the 2 blue water drain petcocks.
FUEL LINE THREADS INTO EACH END
Early Mastercraft TBI, LT1 and some Monsoon engines, located after the fuel pump Indmar Pt # 556003.
Note: Late 1999 and up Mastercraft's use a proprietary in tank fuel filter. Also 2007 up Malibu uses a in tank filter.
This filter is now being used on 2013 and up Indmar engines with in tank fuel pumps. It is located on the engine.