Indexing Spark Plugs

[Roy W.]

Will indexing spark plugs putting the open side of the spark plug gap toward the intake ports help on a bassboat with a 2000 175 EFI Mercury, or is this only for the ultra high performance rigs.

[Russ]

Others do not. I do not, only because the difference couldn't be measured while on a dyno. Once the flame kernal is started...it's started and the flame propagates as it's going to, whether it's done with indexing, 1 plug or 2 plugs.