How many people here use HO alts? Where di you get yours? How much did it cost? Do any auto manufacturers make them, or are they strictly aftermarket? Do you need a specific alt for a specific car, or are they more or less generic? I drive a 1999 Honda Civic EX sedan. Not sure what size alt I have currently, but I may look to upgrade sooner or later. Any information would be appreciated.

I do. see my high output alternator source post a little further down. Yes, most alts are car specific.

Thanks for the replies. I'm running about 1100 watts all said, and I get some dimming. But I might eventually upgrade to a more powerful setup, and 70A just won't cut it...

I use 1 in the Mini. Went from 35ish amps to over 180. It was built/ modified specificaly for the Mini. As of yet I couldn't find an manufacter to supply 1. As for price it was an gift from my father he had an friend that owed him an faviour. With his and my time for the modifying and building I'd say around $600. But well worth the time. Look at GM's alt's they seem to adapt resonably easy.

Just get a Buick/Cadillac alterntor. 140 amps stock, and it should fit in with only minor modifications (like an extension bracket).

Way cheaper than something built up, and probably work better at idle than something custom.

Honda altenators spin in the opposite direction of Gm. Also the computer is hooked up to it. Get a Honda specific alternator.

Thanks for the tips.

and what does that have to do with it?

If the built in fan is spinning in the wrong direction, it won't cool as effectively as it is designed, reducing the lifespan greatly.