Ballast resistor wire removal

[Greasyfingers]

I have been able to find out answer's too most of my questions through search's, but this one has gotten me thoroughly confused. I put a GM HEI distributor into my 74 bronco and didn't realize there was a resistor in the factory harness and I'm not getting the 12v needed to run correctly. I know I need to bypass/remove the resistor, but what's confusing me is the fact that there are two other wires with the resistor wire that tie into the positive coil feed under the hood. So, do I run a wire directly from the ignition switch eliminating all three wires or do I just eliminate the resistor and tie the three wires back together to feed the single wire going to the coil?

Any info to get this squared away would be helpful
Thanks,
Aaron

[ntsqd]

Re: Ballast resistor wire removal

GM HEI's are power hogs, they really need a dedicated feed of at least a 12 gauge wire and preferably a 10 gauge wire. Routing their power thru a typical ignition switch isn't the best plan. Find an ignition 12 VDC source and use that to trigger a relay to switch battery power on and off.

[Greasyfingers]

Re: Ballast resistor wire removal

Hmm makes me think I should go back to the original system. I really don't want another piece in the ignition as a possible failure point.

[ntsqd]

Re: Ballast resistor wire removal

Everything is a failure mode.

A Hella, Omron, or Bosch branded relay is a LOT less likely to fail than an OEM Bronco ignition switch. Do what you want, but I'd use one of these relays: http://www.delcity.net/store/Skirted...2.h_811820.t_1 with one of these pigtails: http://www.delcity.net/store/Hella-I...9.h_808970.t_1, carry a spare relay just in case, and quit worrying about stuff that the OEM's have sorted out and made last thru the end of their warranty period.
I use one like above for my electric fuel pump.

[Greasyfingers]

Re: Ballast resistor wire removal

I'll take your advice and add the relay. I just read so many different posts about this subject I couldn't make a clear decision on what to do.
Thanks

[DirtDonk]

Re: Ballast resistor wire removal

I prefer relays too. They're very reliable and let all the power get to where it's supposed to go. Just a little more stuff to do is all. Gets you "in tune" with your electrical system, so to speak.
They can and do fail of course (hence the spare mentioned above), but if done right, and you use good quality products, they'll probably outlast most other electrical stuff on your truck. Including the factory switch like was said. Putting too much load on them just shortens the life. Like wiring the modern PMGR starters directly to the switch. In those cases, using the original fender mounted starter relay to energize the new solenoid on the starter is just good practice for lots of reasons.

But back to the HEI, in a pinch you can bypass the wire like you were thinking. I wouldn't necessarily make this a permanent solution, but it would get you going and back on the road right away and give you time to collect the parts needed to do the upgrade. If this isn't your daily driver though, just wait get the relay and do it just once.

The only part of the resistor that is in the factory circuit is under the dash where you can't easily see it. Everything you see under the hood is standard wire. The reason you see two at the firewall connector is that the Brown wire from the "I" terminal on the starter relay runs to that point. From there to the coil, the Red w/green wire goes to the coil positive (now to the HEI) but a second wire there would have been for the original radio-noise suppressor. Looks like an ignition condenser/capacitor/thingy because that's basically what it is. Did you have one of those?
That might explain your additional wires.

Because you don't need any heavy duty wires to energize the relay, you can simply use the old Red w/green wire under the hood and connect it to terminal #86 on the relay.
Some relays have diagrams showing what wire goes where, so follow them instead of me. But then again, ntsqd can probably tell you for sure and even explain how to connect the other wires to the relay better.

If you decide you really don't want to use a relay (after all that!), you can splice into the Red w/green wire right at the back of the ignition switch, run it to the HEI and hope for the best. Might work just fine. We'll probably never know if it's what caused the eventual death of your ignition switch, or if it was just getting old to begin with!

Have fun.
And definitely let us know if you need the wiring rundown on a relay in the system.

Paul

[Broncrick]

Re: Ballast resistor wire removal

Many Bosch relays on mine, only fail was a junkyard one I got

[Greasyfingers]

Re: Ballast resistor wire removal

Wired in the relay and there's already a noticeable difference in how it's performing. Now to just finish cleaning up and routing the new wires. Should be back on the road this week. And than on to the next project. Whatever that maybe.

[BRONKEN]

Re: Ballast resistor wire removal

Aaron, what part of Morgan Hill do you live there are a few of us that live there too.