RE: refalcon ignition zdz 80
typically the Falkons liked just good , solid amperage 4.8 volt the new ZDZignitions will accept the A123 as is
don't use old crummy tired 4.8 cells get a good pack such as as an Intllect from Cheap Batery Packs .com
low output cells can damage the ignitions
When the original supplier of ignitions , Vlach,first offered ignitions he warned about this.
some latest types are not as fussy but a solid 4.8 is very desireable
the problem is possible voltage drop as the ignition instantly tries to "fill" with current .
that's the simple answer but take it for what it's worth.