HEI HEI

[dzorde]

Just had a look at the Moto data sheet for the MC3334, this shows dwell as
being set by an external cap and some internal reference buffer circuitry
linked to the current limiting circuitry.  To me it seems that if you
decrease the coil resistance then it will automatically reduce the dwell
because it only allows for a set charging current, this being determined by
a trimpot to the current limiting circuitry (according to the data sheets),
you may need to reduce the charge current a bit to avoid burning out the
coil.  Probably sounds really confusing, so check out the data sheets.

On another note, has anyone looked at the MC33093, MC33094 and MC79076 all
of which are very similar to the above unit, but with extra features such as
car push starting capability, coil current limiting, etc.

Also anyone looked at the MC33293 quad fuel injector driver, you can
paralled the outputs if required for lower Rds-on and higher driving
capability, fauld output indicator if a load goes open circuit, etc.
Definitely worth a look.

Dan     dzorde at geocities.com

>One more twist to the HEI problem, if the 4 terminal modules do have dwell
>control, is it just time base from the charge on a cap. What I getting at,
>if the HEI coil is 2 ohms (Just guessing, anyone know) on the primary side,
>and I use a different coil, lets say the dual post ones that are around .6
>the dwell time could be way off, and toast the dual post coil. I This all
>depends on the primary coil resistance and the amount of dwell. May not be
>a big deal, but the thought has crossed my cone shaped mind.
>
>Sandy
>