Posted for "Ed Anderson" <eanderson@carolina.rr.com>:
I guess my age is beginning to show.  I don't understand why you would want
to undertake a modification that provides questionable benefit?  If you want
the security of being able to fly home on just the trailing plug along (that
I can relate to)  then changing the ignition of the trailing plug to fire at
nearly the same time as the leading edge (15 Deg sooner than normal) will
provide that power.  Tracy Crook's ignition/EFI system does just that AND
you CAN produce near full power (my rpm drops about 50-75-100) when flying
on just the trailing plug.  So you do not need to make the modification for
that reason.

Now if there is some magical increase in power (doubtful in my mind - but, I
could be wrong) by undertaking to enlarge the trailing sparkplug combustion
chamber hole then it might be worthwhile.  Perhaps Lynn will undertake this
experiment and report the results - how about it Lynn??

Just my 0.02 worth

Ed Anderson