After going Efi, which starter solenoid and alt wires are to keep on a 75?

[rjrobin2002]

I installed a Efi harness on my 1975 bronco and it just required a key start and key on source which I tied into at the starter solenoid. While doing this swap I also am using the explorer 1 wire alt. I am wanting to get rid of some wires and convert to a marine terminal block instead of the solenoid as my junction. What wires on the solenoid feed the fuses and what not?

 

[DirtDonk]

Standard factory Bronco chassis harness still, or updated aftermarket? If updated, which one?

For the start feed for the computer, you would leave it on the solenoid/relay.
For keyed power, you don't want that on the solenoid anyway, and should find another source. That one could be on an extra terminal block/stud, but would still have to be controlled by the iginition switch.
Should want a third power, which would be full time power. That one is appropriate for the battery side of the relay, or your separate terminal block as long as it's powered by the battery, independent of the key.

Paul

 

[Viperwolf1]

The 10g wire (should have a fusible link on the end) powers everything inside the Bronco. You need that to have 12V constant power. Ignition switch won't work without it. Between the fusible link and the 10g wire should be a yellow wire going to the voltage regulator. You don't need this with the explorer alt.

Should be another yellow wire that feeds the horn relay. That needs 12V constant.

Brown wire going to the "I" terminal you don't need any more.

Red-blue wire going to "S" terminal you need to energize the starter solenoid. You will need a PMGR starter to get rid of the fender solenoid. This wire goes to the small terminal on it.

You can also get rid of any other wires going to the old voltage regulator. Should be orange, black and the yellow already mentioned.

You will need to run the new alternator output directly to the battery or battery connection at your terminal block. Use at least 6g wire. You can take the old alternator output 10g wire and connect it with a fusible link to the same B+ point. This will help carry the current to the inside so everything will have plenty of amps to run.