Relays for ignition, VR, choke and adding AFR?

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skidmark

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I’m using blue/brown wires, ignition #1 & #2 tied together for switching on a new relay.
Relay feeds new HEI/e core coil conversion, VR and alternator field and choke, also adding AFR.
Should any of these be powered separately with another relay?
Or can one do it all?
Any and all suggestions appreciated.
 
I’m using blue/brown wires, ignition #1 & #2 tied together for switching on a new relay.
Relay feeds new HEI/e core coil conversion, VR and alternator field and choke, also adding AFR.
Should any of these be powered separately with another relay?
Or can one do it all?
Any and all suggestions appreciated.

The way these cars came was with the blue VR wire tied in with your blue and brown ignition wires as well as the choke wire.
The ignition doesn't need a relay unless you have a low power situation to your coil. (some do it though anyway)

The alternator field could be on it's own relay if you want, because it does draw some power when it's needed.

Now all that said, here's my opinion and solutions.
I put the VR blue wire on it's own ignition activated relay with only about 16 inches of 14 ga. wire to the battery stud on the starter relay.
This gives the VR a good close read of battery voltage which helps with bouncing voltage.

Everything else can run without a relay at all taking into account your wiring is not causing voltage drops.
I also have a 30 amp "acc relay" under the hood connected direct to the battery stud on my starter relay for other things.
(electric fan, fuel pump, and such)
Then instead of having a fusible link I run a 30 amp self resetting circuit breaker for all cabin power including stereo, internal lighting and acc's.
Pretty much all internal and external lighting on my car is LED except for the headlights and those are on relays (one for each bulb filament) so it's not possible to loose both lights at the same time because of one bad relay.

The MAD bypass and LED lighting makes a HUGE difference in available power.
My lights don't dim at idle with the brakes or signals on, nor do my wipers or heater blower slow.
For example, two normal brake light bulbs uses about 5 amps.
My two LED brake lights use less than 1/2 amp for both, so that free's up 4.5 amps for other things.
 
Like what you suggested, good info about the circuit breakers and LED’s. I just wanted to keep loads on engine bay side of firewall and to ensure full voltage to these.
Just trying to do it right not being electrical savvy even though my dad was an electrical engineer somehow I missed that talent.
My only question is about this quoted suggestion below. Not sure about the 16” of wire, starter relay is about 36” from VR?
I put the VR blue wire on it's own ignition activated relay with only about 16 inches of 14 ga. wire to the battery stud on the starter relay.
 
The MAD bypass has been done.
I found this drawing here. I’ll use this for the VR/alt field relay. I’ll use the same blue wire to trigger both relays. The other relay feeds an e core coil, choke and AFR. Does that make sense or is there a better way?

114C8FA0-23DC-4569-8F76-50564F23FCD5.jpeg
 
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The MAD bypass has been done.
I found this drawing here. I’ll use this for the VR/alt field relay. I’ll use the same blue wire to trigger both relays. The other relay feeds an e core coil, choke and AFR. Does that make sense or is there a better way?

My relay for the blue regulator wire is pretty close to the regulator.
I just remembered that I moved my regulator to the drivers inner fender between the firewall and starter relay when I put my HEI in.
Now it's just a short run to the starter relay.
The point was to make the blue wire as short as possible and a little over sized.
That diagram is good for using a relay on it, and the way you are going about it seems fine.
 
Thank you for your help! Nice to have another set of eyes on something I’m not 100% sure of.
My relay for the blue regulator wire is pretty close to the regulator.
I just remembered that I moved my regulator to the drivers inner fender between the firewall and starter relay when I put my HEI in.
Now it's just a short run to the starter relay.
The point was to make the blue wire as short as possible and a little over sized.
That diagram is good for using a relay on it, and the way you are going about it seems fine.
 
Thank you for your help! Nice to have another set of eyes on something I’m not 100% sure of.

You are welcome.
There are so many ways some of this stuff can be done it's ridiculous.
 
so i see TrailBeast's thinking on the VR getting a good signal, but load wise, is this really making much difference vs the stock layout?
 
Anything that can be done to relieve the load on your ignition switch and wiring is a good move IMO.

Seen way too many cooked dark blue ign wires exiting the column or in the harness.
 
Anything that can be done to relieve the load on your ignition switch and wiring is a good move IMO. Seen way too many cooked dark blue ign wires exiting the column or in the harness.
yup, and that leads us into the ammeter and bulkhead connector and ... i was wondering if someone has figured out how much you save putting the VR and field wire on relays. at some point though it gets marginal or not worth the trouble
 
yup, and that leads us into the ammeter and bulkhead connector and ... i was wondering if someone has figured out how much you save putting the VR and field wire on relays. at some point though it gets marginal or not worth the trouble

The lightening of the load is minimal, and as you said, for the signal.
For taking loads off the cabin wiring crackback's headlight relay kit is HUGE.
That kit also takes a huge amp load off all your headlight related switches as well.
Lets say for the sake of argument your headlight switch and hi/lo switch normally have 10 amps running through them at any given time.
The headlight relay kit reduces that by more than 50% depending on what external lighting you have.
 
oh ya, headlights are a nobrainer. i have an H4 setup from slantsixdan ready to go, if i ever get back to the front of the car
 
Had concerns about the bulkhead connectors and ignition switch. For HEI conversions some suggested relay power for Hei ignition. Seemed like a good idea to have direct power.
I have installed splice in relays for headlights. Kind of regretting that and should of looked harder at crackedback’s harness. Going to run it for a bit and see how it works.

The lightening of the load is minimal, and as you said, for the signal.
For taking loads off the cabin wiring crackback's headlight relay kit is HUGE.
 
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