Ignition Book

[SRavet at bangate.compaq.com]

wturner at acorn.co.uk (William Turner) Wrote:
| 
| > ~ the multiple spark is also mostly marketing jazz -- someone on the 
net
| > ~ reverse-engineered the msd box and discovered that the sparks count
| > ~ down as rpm increases, until it's down to just one spark above 
~3500rpm.
| > ~ 
| > But the average RPM range of the average highway vehicle falls well
| > below 3500 RPM, so there is benefit.  
| 
| Excuse my ignorance, but do 'Splitfire' sparkplugs fall under the
| heading of being multiple-spark devices? Do they spark twice at the same
| time, or sequentially (as MSD systems appear to do). And do they
| actually have any benefit? (obviously, racing rpm's are going to be
| well in excess of 3500, but I assume multiple-sparks enhance fuel
| economy at the lower RPMs).
| 
| William
| 

A splitfire plug only fires as many times as the ignition system does.  
Which means usually it fires once, unless you have an MSD or other multiple 
spark system.  The fact that the electrode is split makes no difference.  
Only one arc will form.  The only way to get simultaneous arcs would be to 
have two wires, and either two coils or a single dual output coil.  
Otherwise the arc (like humans :-) will take the path of least resistance.

-steve

Steve Ravet
sravet at bangate.compaq.com
Baby you're a genius when it comes to cooking up some chili sauce...