| In a message dated 7/9/2006 7:21:56 PM Eastern Daylight Time, 
75TR6@tr6.danielsonfamily.org writes:
> He suggests using a starting point of .035 versus the
> normal .025. I've been still gapping my plugs at .025. What will be the
> symptoms if the gap gets too big? And what do you gap at with the Sport Coil
> and no ballast wire?
> 
Bob,
I think that the theory behind setting a wider spark plug gap when using the 
sport coil or any coil which raises the voltage to the spark plugs is to take 
advantage of a hotter spark from a spark across a wider gap.  The standard gap 
of .025" with a sport coil won't allow the spark to be any hotter than a 
standard coil would produce over a .025" gap.  But, a high voltage coil can 
span a 
larger gap and generate a hotter spark.  Of course, there's a theoretical 
limit to the wider gap where, even with a high voltage coil, the plug would 
misfire (I don't know what that limit is).
I've experimented with various spark plug gaps on my TR6 with a Lucas Sport 
Coil and I've come to like .032".....no scientific data - I just like the color 
of the plugs when I change them each fall.
Interesting question on spark plug gap using a sport coil with or without 
ballast wire.  I would guess that the manufacturer of the coil would design the 
coil to produce the same secondary voltage regardless of ballast (12 volts vs. 
8 volts)....it's all just a matter of internal wire size and number of turns!
Chip Krout
Delaware Valley Triumphs, Ltd.
Skippack, PA  USA
'76 TR6 CF57822U
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