Automated alternator delete

[oldtamiyaphile]

Originally Posted by serialk11r

The higher the load, the less efficiency you gain from adding load. If the engine happens to be idling or DFCOing, you might as well charge the battery. This is how the new BMWs and Mazdas work.

This is how all new cars work. Problem is at hypermiling speeds/ revs, I found my smart alt is basically reluctant to keep the battery charged. You have to downshift during DFCO to get any decent charge, and then it's only for a few seconds.

They actually essentially have three modes:

Idle: No charging at all - battery voltage around 11.7-11.9. This happens on a full battery or when accelerating. I drive about the first 5 miles in this mode each morning (still goes into regen when it can).

Normal charging: Maintaining roughly 12.8v

Regen: 14.5V on overrun - you might not get as much regen as you think especially if you have eco friendly tall gearing. My Fiat has two regen modes, ~14v on overrun, 14.8 on overrun +brake.

Also if you EOC, you'll probably find you want the alt on all the time that the engine is running.

Personally, I mostly see value in an alt cut out at high loads, especially in a small car, but even that would be a problem during EOC.