Greetings!

I have a problem and need some advice. I am restoring a ’77 VIP, 190 hp, with an OMC 302 Ford. I have converted it to electronic ignition using an “Ignitor II” distributor conversion, an “Ignitor II” coil and “Ignitor” 8mm plug wires.

Problem – Without a load at the dock, obtaining and maintaining the book rpm of +/-4000 is no problem. However, on the water as the rpm is increased, the engine runs excellent all the way up to about 3500-4000 rpm. Once reaching this range, the engine runs very strong for several minutes, and then it begins to miss and fire back through the carburetor.

As power is reduced, the misfiring continues on down to around 1000-2000 rpm, and then once again the engine settles down. If the power is immediately taken back to idle, all indications of misfiring stop and power can then be applied. Extended running at or below 2000-2500 does not produce any problems.

Any ideas or recommendations will be appreciated.