Champions are best for an OMC engine.<br /><br />Spark plug was originally a J6J gapped at .030". They've been discontinued but the J6C is widely available. It's just got a slightly different ground electrode.<br />Some people find they get a better idle from a slightly wider gap. It can be worth experimenting with if you troll.
Use the J6C, tyee.<br /><br />If you troll a lot you will get better operation with a .035-.040" gap. For high speed operation you should use the .030" gap.<br /><br />Many users who use their engines both ways set gaps at .035".
