"electronic" Coil For High Energy Unit ?

[Tham]

Does anybody know if the older high energy electronic ignition

unit by Silicon Chip magazine (June 1998, kit by Dick Smith)

needs to be used with one of those "electronic" coils ?

 

These coils, which usually do not have a ballast resistor,

typically come with those stock reluctor-type distributors

with built-in ignitors.

 

This is because I have been using the high energy ignition

with my Corolla 4K engine's standard coil (with ballast resistor)

and I think it is overheating the coil. Several times, I had to

pull by the road when the engine began to idle badly, sputtering,

kind of like a way-off idle mixture setting. Initially I thought it

was the ignition unit's power transistor or IC giving problems,

but after cooling down the engine, it appeared to run fine again.

I'm using the points to trigger it.

 

I think the standard coil cannot handle the extended dwell set

by the ignitor. I've reduced the variable resistor setting (VR1)

in the Silicon Chip unit to the mininum, giving 0.25 volts for

a coil current of only 4 amps. The coil still runs very hot at this

setting, almost burning to the skin.

 

Are those "electronic" coils made to handle extended dwell,

or are they different in some other way ? These type of coils

can usually be purchased in spare parts shops in Malaysia

and are made by "Diamond" of Japan.