voltage drop to distribitor

Every car has an electrical system. Here's the place to learn all about it.

Moderator: 2088 bob

Post Reply
weldvair
Posts: 191
Joined: Sun Apr 20, 2014 6:24 pm
Location: st cloud fl

voltage drop to distribitor

Post by weldvair » Mon Mar 02, 2015 5:18 am

I am rewiring my 71 & have a question......does the Ghia stock wiring harness have a voltage drop
resistor in the wire going to the distributor or does it get full 12v. :)

thanks Don
retired mech engr living in central florida

User avatar
sideshow
Posts: 3280
Joined: Mon Oct 27, 2003 2:00 pm
Location: suth'ern oraygun yusa
Contact:

Re: voltage drop to distribitor

Post by sideshow » Mon Mar 02, 2015 10:31 pm

No, that is done internal to the coil.
Yeah some may call it overkill, but you can't have too much overkill.

User avatar
Piledriver
Moderator
Posts: 21913
Joined: Sat Feb 16, 2002 3:01 am
Location: Van Alstyne, Texas

Re: voltage drop to distribitor

Post by Piledriver » Tue Mar 03, 2015 5:12 am

sideshow wrote:No, that is done internal to the coil.
It is supposed to be that way on the stock and German Blue coils...

Many aftermarket coils (including some alleged Bosch blue coils) need an external ballast resistor.

There is actually no real downside to using a coil with an external dropping resistor:
It keeps the heat out of the coil.

Note that the setup will probably work a lot better if you use the ignition wire (runs from battery>switch>back of car) to control a relay powered off the alternator power stud or off the starter so the ignition sees 13.sumthin volts instead of ~8-9.

Of course if you have programmable ignition with adjustable dwell time you can use a much higher output coil if so desired.
(I'll argue this makes more of a bang for a buck than injection, although having full control is of course mo betta)
The stock cap/rotor and HV wire setup are still a reliability issue as always if you go that route.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

Post Reply