help with amp bypass or parellel

being you have read my replies is hepfull to make this.

how I would do?

if you have a powerfull alt able to feed everything iddling, you won't have any problem to keep the ammeter working, even if is still the stock 40 amps alt.

A low charge alt won't ever suck enough power to get a full load charge reading at regular RPMs. And if does, will be for a minute or so.

but if your source everything from batt side keeping the ammeter, you'll have mostly sure a "ghosty" charge reading wich is not really a charge job, but really a sourcing job for the newer accesories. Is then, an unnecesary stress and load for the charge system, meaning this, wiring, terminals, ammeter.

The ONLY moment you should worried keeping the ammeter and sourcing everything from alt side is if alternator says byebye, or if you turn off the engine and keeps sourcing the devices/accesories somehow... i.e. fans relay being sourced from a constant power source instead keyed, but if this is the case, these will turn off by itself once engine gets cold, which should be more less quick.

the question is... do you want to keep the ammeter or not ?

myself, I wouldn't get worried as in fact really do. I have 6 relays sourcing my car with stock in everything but just halogen headlights, my 40 amps stock ammeter working, and stock 80's mopar replacement alt. All relays sourced from alt side straight from ammeter stud ( all relays inside the cab to be hidden making a cleaner engine bay view without splices anywhere ). Well of course, these 6 relays will be never working together, just 3 max, but normally 2, if I turn A/C in low speed and headlights. If turn on A/C on mid or high, 3 relays, since low speed is allways activated no matter the speed when you trun on the A/C( factory design on 70s Mopars ), but still just 2 getting the load.

next question... have you calculated how many amperes you'll need to source everything, and how much amps gives the alt iddling ?

THIS is the main to be answered... after this, you can decide which way to go.

I've seen plenty of charred Mopar instrument panels or firewall connectors over the years. The original design might have been okay in the 60's, but it doesn't hold up to modern electrical demands. The firewall connector is probably the weak link rather than the ammeter, but the ammeter will melt if you send enough current to it.

The Mopar engineers started to figure it out in the 70's. They ran heavy gauge thru the firewall on some vehicles and they started to shunt around the ammeter.

Actually I'd say mostly of ammeter and bulkhead fails are related to 3 BIG stupidities!!!

1-hook every existant newer accesory to batt
2-upgrade the batt with a more powerfull one, keeping SAME FACTORY underrated alternator
3-the factory guilt misconception ammeter is an alternator gauge where really is a batt gauge

and these three are proportionally related electricity ignorance

every body is worried about some electricity burn around, but our car works with EXTREMELLY DANGEROUS GASOLINE ACTIVATED WITH A SPARK INTO A CILINDER!!! and quite often with backfires trhough carb due whichever reason.

If we use gasoline to make work our cars and everything takes care correctly about it, why not we do the same about electricity ? without any hack up job needed for that!!! just knwoledgement.

mantenience and knolwedgement will save you.

would be great ppl begins to understand about electricity, the same than takes cares about understand a camshaft!

My brother's 77 Dodge truck had a melted Amp meter that caught fire and damaged his dash. A voltmeter also will show you immediately when your alt. can't keep up.