The OP is considering and dreaming the wide range of possibilities available :), and trying to see what is possible.
Excellent input MEX. This 70 amp ND alternator will always be able to exceed the amperage of the 50/120 upto 70 amps? The current Single V belt that powers my alternator only goes from crank pulley to alternator to ACcompressor. The alternator mount provides the tension adjustment. I have No Idler Pulley. The power steering and water pump are on another V belt with the PSP providing tension adjustment. The Smog pump is on its own V belt to water pump.
Or perhaps I misunderstood and you are saying to use an Idler pulley on the ND alternator for the smaller size so it spins faster, and can always keep ahead of the 50/120?
There are times when my Solar controller is seeking 14.4v and the Ecm chooses 13.7, and the solar is partially running vehicle electrics, so perhaps the additional charging source is not going to smoke the ECM or fire the CEL as it has not fired the CEL when this has occurred previously. I cannot pass a smog test with the CEL illuminated.
If I go the Dual alternator Route, I'd desire to just have the current 50/120 alternator feed only a dedicated Engine battery, and the secondary alternator would feed whatever battery I use for a House battery. My fear of this method is the shared Ground of both alternators screwing with the ECM's voltage regulator. I fear the magic smoke escaping from the engine computer.
If this fear is unfounded, I'd put an adjustable voltage regulator on this house battery dedicated alternator to give me that manual voltage control I desire. The alternator possibilities would be much wider, but anything more than 70 amps is not really necessary.
But all of this is dreamery. Never the less it is fun to seek the ideal possibilities available.
I don't have the disposable income to seek a smidgen better battery charging via my alternator or add another one. I have enough other projects to consume any free time.
14.9v is high, 13.7 irritates me when the battery is depleted, but the AGM battery still exceeds my expectations in my nightly load testing regimen. I should be happy it allows more than 14.2.
I might just have to keep pushing this AGM, and I can put in a tiny 'jump assist' AGM, for if I push too far, and can't wait for a few hours of sunlight to start my engine, or Plug in the Meanwell, or get a jump from some other vehicle.
The 50/120 is nice as it pulls in all air from the back, and I can aim a snap switched fan forced cold air intake at it to increase its lifespan, already got the fan, already got the flexible 3 inch pipe, already have a hundred other projects.
Thanks for the input.
