Spark Plugs

Moderate to low compression: ZFR5N Extended reach

Over 9:1: ZFR6-FIX-11 Standard reach Iridium

Over 11:1, N2O/Forced induction start looking into colder racing plugs. NGK and Champion have plugs. Don't have any of my data as I'm on a business trip. There is a ZFR7 plug listed, but I haven't played with it. (Peaked at 11:1, but backed things off to 10.7:1 to better utilize my cam timing.

As you will find, remove plug sealing rings when using Drool/Hemi tubes. The plugs seal on the aluminum tubes.

Indexing. A waste of valuable time. Net ET gain. 0.00 seconds. Very similar to moving the battery to the trunk in a slant car. :lol:

CJ