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biju
04/09/2007, 07:33 AM
modsters:

the positive post to our stock alternator has two small 10gauge (white) wires that run up to the (engine bay) fuse box. the alternator is then fused at the box with a 100a fuse ("Main"). that then runs out to various sources including to the positive post at our battery.

i'm reworking the wiring scheme so the positive post of the new h/o alternator is wired directly to the positive post of the optima yellow-top, (which is then run in parallel with two more optima's in the rear).

the (new) direct power line from the alternator to the battery will initially have an external fuse of 100a (since that's what it had in the fuse box).

(following me so far??)...

the (2) 10ga wires that used to run from the positive post of the alternator directly to the fusebox will now run from the positive post of the battery into the fuse box.

Questions:


is there anything inherently wrong with doing this (or anything i might be overlooking and need to be aware of)?
i'd like to increase the fuse rating of the new ANL fuse inline between the alternator and battery to maximize current direclty to the batteries - how would i determine the max size i can get away with? what is it based on?


thanks all.

-biju.

Joe_Black
04/09/2007, 08:49 AM
I'm not 100% on this, so this is merely "cautionary": The two smaller white wires may be either for the field on the alternator or the instrument idiot light. If for field then you could possibly be discharging your battery whenever the VX isn't running, meaning a stone dead battery if left to sit long enough. If for the idiot light then it would either never illuminate if there was an alternator failure or stay constantly illuminated. Plus you could be introducing some nastly line noise into the electrical system as well since the alternator produces AC which is rectified to DC by that little teeny-tiny voltage regulator.

If I have time this evening I'll check the factory wiring schematic on the VX and the type of alternator we have. Unfortunately I just don't remember much about it since fiddling with the GM upgrade a couple years ago.

biju
04/09/2007, 10:42 AM
Thanks Joe. Any help is appreciated.

I do know there are two smaller (22ga?) wires that come from the alternator pigtail that also go into the engine bay fuse box - and I'm clueless as to what those are/do.

My logic is - what's the difference if the two white (10ga) wires that carry the positive charge from the alternator, instead get their charge from the positive battery post?

I'll wait to hear back before continuing on....