So I just read that I need to re-wire my alternator. I searched and even googled but couldnt find any info on how I have to rewire it. Does anyone have some info on this?

 

is this what you need?

also later than s4 NA alt equipt cars will have a double up B+ wiring and larger main fuse
you can add another B+ with 50A wiring and another 30A blade fuse to the battery or starter to supplement the circuit of the old as an uprate

 

Nice info!

 

sorry if this is a stupid question, but is for wiring the alternator up to a haltech. I'm just getting started with my E8 and trying to figure out the aux output fo the alternator control.

 

which car/alt ?
s4 is differnt to s5
and later mazda alts like miata need a PWM
( which i assume is what you are asking )

 

it'a a s4 86

 

then you dont use up an aux out for it
the s4 needs a signal from the key switched ignition, as distinct from s5 and s6 requiring to be "live" all the time with sig from the battery

get them onto the wrong car wiring and the system will constantly drain or overcharge, depending if s5 into s4 or s4 into s5
( hence the diagrams above )

so, as such the alt has nothing to do with the E8 , but all to do with the cars original wiring config

you have s4 car, with s4 alt , then the old plug should go back into the alt, and be AOK
( the original warning light and charge reference will still be there )
use that haltech aux out for something else !
though i would recommend the B+ wiring double up that later cars will have
and later upgrade the alt to s5 or s6 ( with attention to signal wiring )
and fuse to 100 amp if using big fuel pumps