And yet, you can't see the problem with adding a big alternator into a system with full load ammeter designed 50 years ago for a weak generator and small battery?
Ok, one last time on this thread then tripleblack gets the last word, I’m done here. First, I don’t promote the use of the ammeters to anyone, I do challenge miss-information about them when I see it. You want to by-pass your ammeter, do it, I don’t care. But when pushing that modification to others it should be based in and backed-up with facts and not your miss-guided assumptions and or opinions. Chrysler, and some other manufactures, used alternators with a battery ammeter since about 1960 and up thru the early eighties on some Chrysler built models. Fact is, the driving force then for the move away from the use of ammeters was the higher production costs, cutting costs, no other reason. To the individual who understands changing circuits completely, the battery ammeter can provide significantly more information about the health of the charging system in real time. More than only a volt meter or idiot light. This is the reason it was designed in to system in the first place. May be outdated now but it was ahead of it’s time then.
The fact that the ammeters seem to be difficult to understand and service, higher the costs, with changing automotive technology, more electrical demands, it is likely they would have gone away at some point anyway. 50 years later, they are only dangerous to those who fail to understand them, the effects of the passage of time, the effects adding loads to the battery will cause, and the electrical principals they were designed to monitor. As I have posted earlier, I’ve never experienced a failed ammeter on anything I’ve owned or touched in all my years. Then again, I’ve never blindly connected heavy loads to the battery on anything running a battery ammeter. Any related connections I’ve touched have been properly reassembled to avoid future issues. In some cases, I was by-passing bulkhead connectors back in the seventies. That makes me washed up? So be it.
I don’t recall posting specific info or addressing upgrading alternator capacity here but I would recommend if doing so, there are some other upgrades that need to take place as well. At a minimum running 8ga charge circuit wires, and by-passing the bulkhead connectors, with or without ammeter the charge circuit wiring should be bumped up and all quick connects remove or by-passed.
Numbers? Here are some numbers, in my shop now, two 1972 bodies (mine) and a 1970 E-body with the same basic modified Chrysler designed charging systems with the mods as follows. Optima Red top 800cca, 1000ca, 50ah. Tough stuff 130-amp Chrysler reproduction alternator, externally regulated. 8-gauge marine grade primary charge circuit wires. Alternator output is connected to the input side of an 80-amp circuit breaker mounted on the fire wall. Another 8-gauge run from that same circuit breaker stud thru the firewall to the alternator side of the ammeter where the original 12-gauge dash harness ammeter wire remains (leads to the factory load splice). Ammeter connections are properly tightened and insulators in good shape. The ammeter to battery charge wire is also 8 gauge with a 12-gauge fusible link at the starter relay. The upsized charge wires replace the original 12-gauge wires, nothing is “paralleled”.
The circuit breaker protects another 8-gauge run to the trunk and connected to a 400-watt amplifier (at 13.5 volts that’s a potential ~30-amp add-on, doing the math). A pair of 40-amp circuit breakers to protect the forward light mods are also connected to the alternator out at the circuit breaker. Running a total 560 watts Hella H1 & H4 lead lamps on relays (potential total 42 add-on amps, 30 amps hi beam, 12 amps low beam). A few other non-original loads and factory air and power windows. All loads, factory and add-on are on the alternator side of the ammeter. The MSD controller should be worth about 10-12 amps. Some other connection replacement to reduce voltage drop at the voltage regulator, Anderson PowerPole 45amp rated terminals replacing the Molex ignition switch disconnect to be specific.
Net result? Quite a bit potential total vehicle load and not a single amp of that total vehicle current load, factory and added, flows thought the ammeter when the engine is running as was originally designed. Battery charged, engine running, 130 amps of power available from the alternator, loads on, equals a centered ammeter. Won’t go into details here on the audio system, all quality components used with zero noise artifacts induced. Nothing connected directly to the battery.
Battery charge rate in excess of 15-20 amps? Not likely, never seen anything close to it with above configuration. Too many variables to debate you on this subject here but healthy batteries are limited in the charge current they draw and can accept, it’s not directly proportional the current state of charge. The use of a battery maintainer is recommended anyway, a fully charged AGM draws 200 ma.
When the name calling starts, I check out.
