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upgrade alternator


New Member
I'm sure this has been covered somewhere at some point in here but I'm new to the forum so I had 2 89 lx hatchbacks many years ago and I upgraded the alternator for the stereo systems. My memory is not what it was but I don't remember having to cut into a housing to make the new alternator fit and running new wires to a block and then to a solenoid to make it work. I just bought my wife a 91 gt covertible all stock and everyone says you have to do that now. Am I missing something is my memory that bad can someone please answer this do I have to make these modifications or can I just buy a bigger alternator and bolt on and go. Please any help is appreciated and I'm not a mechanic by any means so no negative comments please


Well-Known Member
They used to (maybe still do) sell an upgraded heavy-duty alternator. It was barely an upgrade, but it did the job. That was before the 3g came out. A 3g alternator swap is easy and light years ahead of the old style. Plus, it gets rid of the flat plug that was a fire hazard. Note: some 3g swaps retain the original main power feed wires, which are the two black/orange stripe wires coming from the old alternator. If you do the swap (you should), get rid of those wires and install a heavy cable from the lug on the back of the 3g to the starter relay or battery.


New Member
I did that newer one wire alt years ago and it charges great, made my own cable that runs from the back of the alt to the starter relay. Pretty easy to do.


Active Member
I did the 3g upgrade along with the wiring adapter kit from LMR. It was straightforward, and the charging capacity has been a great help.