I am looking for advice on what the best plugs, wires, and general upgrades would be for my engines. They are 1997 502 MPIs with the B&M 250 Efi supercharger kits on them. The engines are undergoing a total top and bottom rebuild as we speak. The superchargers were sent off and were rebuilt/blueprinted at Supercharger USA. I run about 4-5 PSI of boost and I am looking for the best plug wire combo as well as distributer to run. Currently I am running the MSD 6M-2 Marine ignition. The fuel pumps are being upgraded with the Keith Eckert pumps; the sea pumps have been upgraded to the "lifetime version" and I am doing all new gaskets, filters, etc. Thanks

pretty open ended question there..... You can increase boost and have your efi reprogrammed for more power.. You can add an intercooler... Stroke it to a 540...cam change, etc.... plugs will be determined when you figure out what you are going to do.

I am going to keep the engines stock and go with the same amount of boost 4-5 PSI. The boat is a twin engine 29 Fever. It will be plenty fast for its size. The engines make about 575-600 HP each but I will not know the exact numbers till we re-assemble and dyno them. Not going to go with an intercooler at this time mainly due to my budget. I was thinking of going with a colder heat range plug, like a NGK 5673-8. The Taylor wires look nice also (the 10.4 wires). I want to make sure I am not just wasting money. I want excellent quality parts.

I would run one heat range colder than stock for the engine...should be good to go...best to have a wideband 02 to tune from...

the ngk-8 plug is good,the taylor wires are good,as are the msd wires.some will disagree,but i like the red msd non marine boxes,i have only had to replace 1 in 20 years.and i use them on all my boats.