Under Driven 200 Amp Alternator: A Bad Idea

I think it'll measure 2.17, because I have a stocker, too. It so happens that the 2.1" that LMR sells is also 2.17, because I have one of those, too... lol! Thank you for the offer, though.

Good stuff, Mike. Any idea what the blower motor specifically was on max?

I slapped that 1 7/8ths pulley on, limited the car to 6k RPM and went out to the street scene last night. The pulley made a huge difference! Also got some runs in with 2 coyotes I wish I could tell you guys about. Looking forward to getting the 2", and getting the limiter back up to 7. This 1 7/8" pulley would spin me up over 18k.

Haha! I just got a mental image of you there trying to get a reading while working the locks and windows, lol!

I'm curious because I notice that the blower drags the voltage down pretty decently. With the a/c, is the only power used due to the clutch engagement? If so, I wouldn't think it's really much of an electrical draw.

To put a bow on this thread, here are my takeaways from this experience:

Alternator pulley specs are not well represented in advertisements.
The stock "2.25-in." pulley measured 2.17".
The "2-in." Powermaster pulley measured 2.05".
The "1 7/8-in." ASP pulley measured 1.69".
These measurements were all taken on the ridges upon which the belt rides with a micrometer.

The only pulley that worked to my satisfaction on my alternator was the ASP pulley, presumably because it gets the alternator up to a ~2,400 RPM shaft speed at my ~900 idle RPM. I'm going to put it back on and take my chances with spinning that alternator nearly 19k rpm. After talking with PA Performance, and Powermaster performance, it is apparently true that at lower idle alternator shaft speeds, the 130 alternator falls off less than the 200 amp. They also say that 130-amp alternators can make upwards of 170 amps at and beyond 6,000 RPM, where they level off at their maximum output.

Both PA Performance and Powermaster told me that the ~18,600 RPM I'll spin the alternator up to is not crazy, and though it's beyond what they'd guarantee, it will probably hold together.

PA performance convinced me to keep the unused 130amp I ordered from them, because they can build it into a 200 amp for an additional $90 + shipping. If I blow up the current one, I'll play it safer and see if the 130-amp does the trick at lower idle speeds. It's nice to have a backup.