Costs/Benefits: EVI vs Carb

[TheSilverBuick]

For reference, my voltage varies about .1 volt on a semi-cyclical pattern on the Skylark, with 105amp alternator, and the T-bird is around .3-.5 volts which isn't great, but I figure the 63 amp (might be 55?) alternator might be a bit under powered at low rpm.

I watch the temp sensors to see how they are reading, or the MAP if the engine is off, but that only tells you if you have a background noise issue (like the radio or such).