My FD alt has been acting weird ever since I put it on my new motor.

At random times the car will run off the battery and will be around 11.6volts at start up. Once I go over a certain rpm(2-2.5kish) it will make a whine and then the voltage kicks up to 13.2-13.7 range.

2 weeks ago out of no where the car over charged in the 14.8+ range even with headlights on. This has gone away and has yet to resurface.

During the day I'll pull any where between 14.7 and 14.2
At night with headlights on it's never over 14.3 and I've seen drops well into 13's

Has anyone had an alternator drop it's voltage with longer drives and heat exposure?

Think it's the regulator?

 

Did you rewire the alternator in accordance with the new S5/S6 wiring?

 

yeah,
One of the back trminals is the constant 12v source and the other is the reference wire for the interior crap.

The 12v constant is looped right to the B post terminal with a 30amp fuse.


I'm almost wondering if this plus crappy coils are the cause of all my problems.
Argh. Me hates Rx7's.
I've already got a back up harness rewired. I just don't want to do all that work with out knowing if that's the cause.

I'll do some multimeter tests to see if I'm getting 12v from the b post.

 

ok,
I put the wrong number.

On initial startup (if it doesn't do the 12v thing) I got 13.7-8 volts
After a couple minutes of driving it settled down to 13.4-5v with running lights on.

Then later on I put the headlights on and I was running 13.0-2v and occasionally would touch 13.4

Does 13.2 sound too low for high load driving?