converting to a 93 alternator in a 87 fc
 

i was told that i could exchange my alternator (87) with a more powerful 100 amp alternator from 3rd gen. keep blowing main fuse. talked to many different people and very confusing.main fuse on turbo 87 is 80 amp alternator 100 amp. changed to 100 amp fuse still blowing and melted down fuse box. so what im getting at is has anyone else trie this or can this car handle the larger alternator? please help if you can.

talk to "silverrotor"

This is a pretty common upgrade and I myself have done it. Im not to sure what would be causing your fuse problem but I am sure that there are many other reasons to upgrade the alternator and very few downsides. If you can find one cheap I say go for it, however I think you should examine your fuse problem more than just replacing things until it stops. Ive learned some things over the years about working on cars and one of the things I have learned is that is exactly the wrong way to do things. Diagnose the problem and then fix it based on the diagnosis.

Re: converting to a 93 alternator in a 87 fc
 

Your problem is you have a short somewhere. By sticking a larger fuse in, you exacerbated the problem.

The alternator only puts out what is required of it. And your stock electrical should not be requiring that much.

when u changed the alternator, did u happen to check the engine ground wire also? (just in the area)
my car had the main fuse blow like twice because the stock ground wire was shorting out... and when my last owner changed the FD alternator into the car, he didn't position it too well... so it forced my intercooler out of place (and i thought i had a blow off valve..... stupid it was a giant vaccum leak in the back of my intercooler)
anyways.... when the ground wire went bad..... it hit my intercooler (and some positive source)

so the alternator's placement and also the ground wires near it or wires around it might be whats happening to you

stupid main fuse cost 5 bucks!