Re: Split-fires Gimmick!

[Rolf Mair <waves@epix.net>]

Want to make a split-fire? Take a Bosch W7DC and a small demmel tool with 
a cut-off wheel, or a jewelers saw, and split the contact yourself. In 
theory, Split-fire does have an advantage, which is only in longevity. 
Electricity prefers sharp edges to make it's path complete. Split-fire 
offers more 'edge' to work with, thereby allowing the plug to last maybe 
a bit longer.

The Real reason the tri-electrode Bosch W7DTC is excellent for 
Watercooled VW and most Audis, with stock ignition systems, hasn't been 
brought up yet. Yes, they last longer and the spark can choose which 
electrode is cleanest to fire, But MOST importantly is the fact that the 
spark faces the upcoming mixture of fuel/air. With a standard plug, the 
mixture must travel around the electrode to meet the spark, which isn't 
as effecient. Ever heard of 'indexing' your spark plugs? American car 
racers do this because their plugs, if installed correctly by shimming, 
can face the intake charge as it's rising up the cyl. The tri-elect. has 
an open face no matter which way you install them. Use them before you 
try those gimmicks called "split-fire". If you are running a Jacobs or 
MSD ignition, you will probably want to use the standard plugs though. 
According to Jacobs, most Hi-Po ign. systems become 'confused' with any 
plug other than stock. Call them up for any question.
sincerely,
r.mair