If you tie the blue and brown together is there any harm with the power back feeding to the ingintion switch (IGN 2)? I'm about to wire up my car and wanted to know the safest, easiest most economical way of wiring a FI Tech. With a factory ignition sounds like diode/relays would be best bet. Does anyone have a wiring diagram of how to accomplish this? @Johnny Mac
Switched 12v source
- Thread starter ScampChamp
- Start date
-
Your mention Factory ignition? The stock distributor and box need to be out of the equation. So just clarifying that. Pending year of vehicle you may have a 12v open slot on the fuse box. I havent heard of interference issues with the blue/brown method, but just my taste, I would much rather find a simple 12v source off a fuse spade, or even a switch under the dash. My 1974 had a random female butt connector coming off the fuse box. Perfect switched 12v.
The car in question is a 71 Dart. So best bet is one of your recommended BBK3601BK distributors with a matching coil, Tying the blue/brown together or finding a switched fuse source and be done with it? Will this distributor with FI Tech timing control?
The OEM ballast resistor was nothing more than a resistor. No diodes in the start and run circuit. So there always was a reduced voltage back feed through the resistor to the ignition switch on blue or brown.
Tying blue and brown together, deleting the resistor does make the back feed measure full 12 volts. No harm done.
This is the one you want for timing control.
PRO SERIES 2 WIRE DISTRIBUTOR | MOPAR SB 273-360 | V8 ENGINE | BLACK CAP
With this rotor.
MSD PHASABLE ROTOR FOR PRO-SERIES BILLET DISTRIBUTORS
Only way to do timing control the "right way" IMO.
The PN you meant to reference in your post, BPP3601BK ( the little hei ) will work, but only in a fuel only setup.
And I do prefer the E core type coil. No oil in it to get hot, or leak.
IGNITION COIL | EXTERNAL E-CORE | 50K VOLT | BLACK
Anything I can do to help let me know!!
ScampChamp
Active Member
hi everyone I fired up my sniper efi yesterday and it’s running great. I’ll add a pic of how I wired up the 12v switched ign as well as a diff one to a toggle switch . Where it says “IGN” means to the Ign1/ign2 wires that were spliced together. And where it says “fuse” means to an always hot 12volts from the fuse box under the dash (spliced in). Simply flipp the toggle switch and crank the key and life is great. Thanks so much guys
Thanatos340
Well-Known Member
Some great information in this thread.
I just went through a similar dilemma with my 71 Duster - 440 in it.
I had no factory wiring as this was a former drag car I was bringing it back to Street. It had been previously wired with all toggle switches and a push button for a the starter. I ripped all that out and wanted to start and turn off the car with the Key and eliminate all toggles.
Also important to me to make sure a Neutral Safety Switch was working properly. I wanted to use a relay for the Run Circuit as well since I am adding a Holley Super Sniper in the future. For ignition I am Using an MSD 6AL-2.
I used an MSD 7564 Solid State Relay Pack (4 Channels) to run Starter Solenoid, Run, Fuel Pump and Fan.
Coming off the Ignition Switch,
I ran ACC to a fused bus for all ACC circuits I would want.
IGN 1 and IGN 2 I ran to the +12 Input for the Run Circuit (Another fused Bus on the output from the relay).
Ran from the Run Circuit Bus to the +12 input on the relay for the Fuel Pump. (Fuel Pump Only Runs in the Run Position and turns off when key is off)
Ran a -12 (Ground) input from the Temp switch to the Fan Relay.
The challenge came in with the Start Circuit since I wanted a NSS working properly. The MSD Relay Pack is a solid state relay and each channel only used a single input (can be either +12 or -12 but not both). Normally on a NSS I would just break the negative side if in gear and use the switch in the trans but that was not an option with this relay pack. So I ran the Start wire from the Ign Switch through the switch in the aftermarket shifter in the car (B&M Pro Stealth) to the +12 side of the Starter Solenoid relay.
Neutral Safety Switch works and I have a clean Run Bus for when I add Holley Sniper later. No Toggles and key turn everything on and off (Except fan which will run even if car is off if needed)
There are probably better ways to do this but this is what worked for me.
I just went through a similar dilemma with my 71 Duster - 440 in it.
I had no factory wiring as this was a former drag car I was bringing it back to Street. It had been previously wired with all toggle switches and a push button for a the starter. I ripped all that out and wanted to start and turn off the car with the Key and eliminate all toggles.
Also important to me to make sure a Neutral Safety Switch was working properly. I wanted to use a relay for the Run Circuit as well since I am adding a Holley Super Sniper in the future. For ignition I am Using an MSD 6AL-2.
I used an MSD 7564 Solid State Relay Pack (4 Channels) to run Starter Solenoid, Run, Fuel Pump and Fan.
Coming off the Ignition Switch,
I ran ACC to a fused bus for all ACC circuits I would want.
IGN 1 and IGN 2 I ran to the +12 Input for the Run Circuit (Another fused Bus on the output from the relay).
Ran from the Run Circuit Bus to the +12 input on the relay for the Fuel Pump. (Fuel Pump Only Runs in the Run Position and turns off when key is off)
Ran a -12 (Ground) input from the Temp switch to the Fan Relay.
The challenge came in with the Start Circuit since I wanted a NSS working properly. The MSD Relay Pack is a solid state relay and each channel only used a single input (can be either +12 or -12 but not both). Normally on a NSS I would just break the negative side if in gear and use the switch in the trans but that was not an option with this relay pack. So I ran the Start wire from the Ign Switch through the switch in the aftermarket shifter in the car (B&M Pro Stealth) to the +12 side of the Starter Solenoid relay.
Neutral Safety Switch works and I have a clean Run Bus for when I add Holley Sniper later. No Toggles and key turn everything on and off (Except fan which will run even if car is off if needed)
There are probably better ways to do this but this is what worked for me.
-
