I'm currently doing some rewiring on my car and have been simplifying a lot of things. I have a one wire alternator w/ the wire run underneath the car all the way back to the battery in the trunk and it works great. I'd like to shorten that wire by attaching it to a junction block (pictured below) I have mounted on the firewall where the main 1/0 wire from the battery attaches to the starter wire. Also have a wire feeding all of my electrical components (ignition, nitrous, etc.) taken from this junction block.

My question is will there be any interference issue w/ these somewhat sensitive components if I let the alternator feed back to the battery at this point? Or does that long run back to the battery and then the battery wire run all the way back to the front of the car eliminate any possible interference?
It's all attached to the battery positive, just a matter of where it connects.

Could I even connect it to the starter relay where it gets battery power on the big stud? That would make an even shorter run.

Excuse me if this is a stupid question, I'm learning as I go w/ a lot of this wiring stuff, lol.

Chip the wire from my alternator is hooked to the same stud on my battery (up front) as my Digital 6 and I've noticed no issues with it to 7200.

If you do that, will it not still make the wire hot and let the engine run, even if you turn the battery disconnect switch off in the back of the car?

I don't know the answer, but just throwing it out there.

I'm wired the same way as your talking.. both
on the race car and the Rampage.. it works
fine so far.. I'm putting on full fuel injection
now so I will see how it is with that type of
electronics

Yep, you're right. Didn't even think of that!

Thanks yall, but it looks like I'll have to leave it the way it is.

On mine I come from the alt to the master then
out of the master to the battery then forward
to the hot post..

The battery, all batteries , will act as a noise filter on AC current from the alternator
EFI systems with super ignition system can have issues

Connecting the alternator feed to the same stud as everything else in the car will eliminate the function of the master switch. The alternator will keep everything running until the engine shuts off. Battery and alternator feed on one side of the master, everything else on the other. That's the simple and effective way to do it. Because of the long run, use a larger gage of wire for the alternator, minimum of 8ga. Also, because the alternator line is now hot all the time, take time too ensure that wire is well insulated and protected to keep it form being shorted to ground.

I have mine wired up like you are wanting to do. I do use a continuous duty solenoid to interrupt the alternator feed though. It does take some extra wiring to make the solenoid work right with the key and everything but the charging system is something I don't ever worry about anymore.

It's been this way for 11 years w/ no issues...big wire run back to the battery from the alternator.

I started off rewiring my nitrous system to add a progressive and it kinda snowballed. I've gotten rid of a bunch of old crap wiring, simplified a bunch of stuff, and throughout this whole deal I've been trying to take some weight off this sled of a car so I can hopefully run a lil faster.

I wish I wasn't so attached to this particular car, but I am, so I'll just have to do what I can w/ it. Otherwise I'd sell it rolling, buy the '68 fastback cuda I've had my eye on, and actually have a car that's light.
But I've had this car for so long and done so much w/ it, I'll never part with it.

If this makes you feel better my 68 Fastback weighs 3600lbs with my 240lb rear in it and an all Iron(r1 block) small block. lol

LOL, ok, that does make me feel a lil better! I've lost almost 10 lbs myself...down to a svelte 325 lbs now, lol. I need to get Ray (sixpackgut) to drive this thing.
I'm seriously thinking about removing the windshield wiper system since I never drive it in the rain anymore. It desperately needs to lose weight, but I refuse to gut the interior of the seats, door panels, etc.
I've even been shortening bolts that hold various things on, lol.

Everyone thinks the all aluminum hemi saved me a bunch of weight, but it didn't at all. It weighs the same as the iron block/aluminum headed 440 it replaced.

This is the style master disconnect I use when wiring cars with alternators.

https://www.waytekwire.com/item/44031/Pollak-51-904-Master-Disconnect-Switch/

I use that same switch but I use the small poles to kill the solenoid on the alternator output.

I like using the 2 pole switch(4 post) also, but route the ignition control (MSD small red wire not the big lead) through the aux pole of the switch.

Then the alternator can be connected forward in the car for less cable length and voltage drop, and no need for heavy relays.

Also when wired this way every thing in the car is dead forward of the bettery disconnect when the switch is thrown. Lots of ways to get the job done.

It should work fine as long as you have good connections and crimps. You can always add a capacitor/filter if you are worried about noise.
Usually, it is the ground paths/connections that cause problems with electronic controls because the sensors are using the ground as a reference point. The input voltage to the electronics is normally filtered and regulated to a lower voltage, like 5-volts.

Chip, if you have a dedicated cable to the starter, you can run your alternator wire to the starter cable stud, also. Leave your ignition system and fuel system wired as is, because they need to power up through the kill switch.

I did the same thing, ran a 4ga copper clad aluminum wire to the back with a continuous duty RV type solenoid.

http://www.madelectrical.com/ IMO check out the electrical tech
there is great info there.