So, i did a serpentine conversion to my non-ac/ps GTI yesterday. i know, its just a dumb gasser, but ive got a fetish with OVERKILL charging/cooling systems!
can pretty much jump start a dead dump truck now, with all the power my car has. brand new over size battery, and a nice big alt!
i used the VR water pump pulley, because the power steering pulley was already gone, damn it! it would have worked OK with no spacer behind the pulley, but i wanted the belt to ride in the middle of the pulley, instead of on the edge, so i built an aluminum spacer for it, then everything lined up PERFECT! belt rides directly in the middle of the pump pulley. belt does not flutter at all.. not at idle, not at WOT.. no belt flutter. its friggen sweet!
i also used the VR6 120a BOSCH alternator.. its the same 120a that the TDI uses. its physically HUGE compared to the 90a alt i took off the car.. has the same W-term/D+ plug as the TDI alt, but with a regular rectangle injector connector, rather than the D shaped connector.. and it bolts right up to the ABA serpentine bracket perfectly.. all i had to do, to be able to use it, was swap the ABA pulley onto the VR6 alternator..
and, according to my butt-dyno, the car is just a little bit QUICKER now.. im absolutely amazed actually. i thought i would LOSE power from the huge alternator, but i swear it added some bottom end torque, just from the bigger spinning armature..
also, since i installed the ABA bracket on an 86 GX engine, i didnt get to install the top right (looking at the bracket) stand off bracket for the alt bracket.. so its bolted to the water pump with the 2 long, bottom bolts, and then it has only ONE bolt holding the top of the bracket to the block.. there was no provision for the top right stand-off bolt, that the bracket bolts to.. i looked the alt bracket over good and well, and i saw no reason that i couldnt safely run the bracket with only 3 of the 4 bolts holding it to the block.. it doesnt flex at all, and really doesnt have to do anything more than hold an alternator.. i should be ok with only 3 bolts right? or should i build up a bracket so i can use the 4th stand off bolt? i also had to make a little aluminum spacer to go behind the timing cover.
oh, and i forgot to mention the best part of the swap:
you know how most every old mk1 or mk2 VW has the "blip throttle to excite alternator" syndrome? well, my charge light now goes out before the OXS light, or oil pressure light!!!
its soo nice not having to manually make the alternator charge, now it just does it without any human input! could also have something to do with the fact that i cleaned every grounding point on the alternator/water pump/bracket, and die-electric greased every metal to metal connection between the engine block, and actual alternator..
anyways, this is DEFINITELY a worth while upgrade, even on a diesel, being that you have to get the crank broached, and use a TDI sprocket..