GM L6 250 Alt/Elect Ign./Coil/Resistor Questions...

[DukesFin]

I'd like to get myself a new alternator, new electronic ignition, new coil and drop the external ballast resistor.

I've got an L6 250 motor and a stringer outdrive. It's a '74 model. Right now, I've got electronic ignition, but I'd like to upgrade to the Pertronix II and get the an epoxy filled coil for it, and also knock out the external regulator.

What do I need to be concerned with when I dump my OLD 30-something AMP AC Delco alternator, upgrade my ignition, get rid of the external regulator and how do I get rid of the ballast resistor?

Note I said "I'd like to..." The suggestions and concerns mentioned here might sway me one way or the other...

Any help is greatly appreciated!

 

[95yj]

Re: GM L6 250 Alt/Elect Ign./Coil/Resistor Questions...

Can't give you any specifics here but changing the alternator shouldn't be a big deal. Make sure it's a marine alternator. You'll need to decide which type, (one, two or three wire) so the rewiring is as simple as can be. Do a search on the web and you'll find lots of info on the differences between them. Generally it has to do with how the voltage regulator is "kicked in" to start the charging circuit.

Easiest way to change the ignition since you're looking to change all of it is to buy a complete set, distributor, coil, etc. Again, you're looking for a marine unit and you want to find something that has an advance curve that will work with your engine/cam/boat.

The ballast resistor just lowers the voltage from 12 to around 9 volts. It was originally used to make the points last longer. I think some electronic ignitions may use them but if the circuit runs at less than 12 volts, nowadays it's built right into the coil. (GM always did this so no resistor needed while I was always forced to carry a spare ballast resistor in my Dodge Dart.) Any ignition you buy today should not need an external resistor.