[s-cars] Speaking of plugs? (not A/S)

[Paul Gailus]

"Indexing" the plugs to move the orientation of the ground
electrode is an old trick. Moroso and others sell assortments
of various thickness washers for this purpose. One reason to
do this is supposedly to minimize any blockage efects on the
flame front emerging from the ignition point at the spark.
This makes some sense if the plug is off to the side of the
combustion chamber, but our plugs are more centrally located.

The other argument is to orient the open end of the plug
toward the intake valve(s) to expose it more to the intake flow.
The advantage of this is less clear to me. For one thing,
the spark occurs later in the compression stroke so
conditions at this point have will have changed from those
during the intake cycle.
But if there are any intake blockage effects from the ground
electrode, then having two intake valves should help
to minimize it.

Paul


----- Original Message -----
From: Bill Mahoney <wmahoney at disk.com>
To: <s-car-list at audifans.com>
Sent: Friday, May 02, 2003 11:48 AM
Subject: [s-cars] Speaking of plugs? (not A/S)
...

> But, also, I have read or heard (that in Pxxxxxx cars anyway) that power
can
> be enhanced by turning the plug in a certain direction towards the intakes
> when installing?  Lie, myth, fiction, somewhat true or true?
> Just curious.
...