Never factor in impedance rise for a daily system anyways. Impedance fluctuates a lot as many factors change.

@ Julian - it's a DC Power 320 amp alternator. Niether MLA or XS Power makes voltage regulators for my vehicle.

Gonna see about a smaller pulley tomorrow.

Also got a comp on Sunday so I'll be building an SPL box.

See what kind of difference that makes

Don't get a smaller pulley without contacting DC Power, they design and put the alternator together for your vehicle to work with your vehicle. My car couldn't get a smaller pulley or the engine would bog down too much at idle even with low loads. Make sure you have a belt with good grip and make sure you have it tight. I had this problem too and I just had to tighten the belt. Some belts will loosen after the first month or so and you need to tighten it again to be tight for sure. Talk to Rob and he will help you out.

What happen to the stetsom amp you had ?

you didn't like it ?

You should be ok with such a beast of alt.

I looked at the mla website : they have 2 models of mla module for Toyota. None of them fit in your Yaris ?

I asked them if I could find one for my car. I want to try one.

good luck

Ahhhhhhhh, wish I knew this 5 days ago. Might have invested my money in different areas. Maybe another alt or one that puts out more at idle

Would 14volt batts be an option?

That's just the issue with most high output alternators vs. stock ones. Stock alternators are built to put out a higher percentage of their max amperage at idle, since when you just drive around like most people do, you idle a lot. Most high output alternators are made to put out their most juice at a higher RPM (under higher engine stress situations), but often that's at the expense of idle amperage output.

I've seen graphs of stock vs. high output alts and the stock one would put out, say, 80 amps at idle and 120 amps at 3,000 RPM. The high output alt would only put out 50 amps at idle but 200 amps at 3,000 RPM.

You must have looked at garbage high output alternators. No alternator from dc power will have lower ratings in any parts of the rpm bandwidth compared to stocks.

However, this was the case when I tried a rewound stock alt to high output. I got about half the output at idle compared to stock. This was also the case with an ebay boss load alternator.

I would dip into the low 12s with stock alternator and an extra deka in the trunk with just a 3k amp, idle or 2k rpm. I don't even get below 13.5 with all lights and accessories on with the 3k amp at IDLE. These are all read from the battery in the trunk.

If u get a custom alt u can most of the time ask the company to build it that it has great idle output.

(and by the way not all DC power alts have good idle output. )