EFI retrofit wiring question
Thread Starter
Race Director
Joined: Oct 2005
Posts: 12,468
Likes: 1,548
From: Camp Verde AZ
C1 of Year Finalist (performance mods) 2019
2017 C1 of Year Finalist
EFI retrofit wiring question
I am /have finished installing a multiport EFI system on my C1 car.
the place I bought it from tells me I need an updated ignition switch to make it fire during cranking. (It cranks but won't fire until i release the switch back to "On") The original arrangement, of course was "on" ran thru the ballast resister to the coil, but during cranking, the solenoid ran power directly to the coil.
i think they just may not know what they are talking about, as I think I should simply take the wire that used to supply power from the solenoid to the coil during cranking, and splice it to the regular "on" wire from the ignition switch (that used to connect to the ballast) that goes to the new relay that powers up the ECU.
Am I missing something here?
Thanks,
Doug
the place I bought it from tells me I need an updated ignition switch to make it fire during cranking. (It cranks but won't fire until i release the switch back to "On") The original arrangement, of course was "on" ran thru the ballast resister to the coil, but during cranking, the solenoid ran power directly to the coil.
i think they just may not know what they are talking about, as I think I should simply take the wire that used to supply power from the solenoid to the coil during cranking, and splice it to the regular "on" wire from the ignition switch (that used to connect to the ballast) that goes to the new relay that powers up the ECU.
Am I missing something here?
Thanks,
Doug
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
You are on the right track. Your old points ignition system ran off of 6 to 8 volts via the resister to keep from burning up the points. The solenoid sent 12 volts to the coil during cranking to provide a hotter spark for easier starting. Your new HEI is intended to run on the full 12 volts, all of the time.
You are both right. You just have two method of accomplishing the same thing. As you realize, the ignition isn't receiving any power during cranking. That is why it fires up, all of a sudden, when you release the key from the cranking position to the run position.
Your new HEI requires 12 volts, all of the time. Change the resister wire from the ignition terminal of the ignition switch to a normal wire, or if it goes to a ballast resister, wire it out of the curcuit. The wire in my C4 is 3 mm, which is the equivalent to 12 gauge. Your ignition switch won't power the ignition circuit during cranking, so as you suggested, revert back to the "olden day's" wiring system, and run a 12 gauge wire from the "S" terminal on your solenoid up to the HEI and connect it with the wire coming from the ignition switch, at the "Bat" terminal of the distributor cap.
A different ignition switch that powers the ignition circuit in both the "start" and "run" positions solves the problem as well. It seems your method is quicker, cheaper and easier.
RACE ON!!!
You are both right. You just have two method of accomplishing the same thing. As you realize, the ignition isn't receiving any power during cranking. That is why it fires up, all of a sudden, when you release the key from the cranking position to the run position.
Your new HEI requires 12 volts, all of the time. Change the resister wire from the ignition terminal of the ignition switch to a normal wire, or if it goes to a ballast resister, wire it out of the curcuit. The wire in my C4 is 3 mm, which is the equivalent to 12 gauge. Your ignition switch won't power the ignition circuit during cranking, so as you suggested, revert back to the "olden day's" wiring system, and run a 12 gauge wire from the "S" terminal on your solenoid up to the HEI and connect it with the wire coming from the ignition switch, at the "Bat" terminal of the distributor cap.
A different ignition switch that powers the ignition circuit in both the "start" and "run" positions solves the problem as well. It seems your method is quicker, cheaper and easier.
RACE ON!!!
