Some more info on >180 amp alternators from Ryan aka fireguy50: RJM Injection Tech — 200Amp Alternator

 

In hind sight, if you want that much power get a 160A 3G, and then use a top quality big @$$ audio capacitor in your audio system. This will eliminate any huge drop in system voltage that would be there without a capacitor....

 

If you decide to go to 200A or more with a 3G alternator and you actually use it at that load, expect to be rebuilding it often...
There is not enough heatsink and internal fan cooling to keep it from melting down.

Ask someone who has a heavy duty electric winch.
A #12,500 unit draws about 530A.
Batteries don't provide that for very long.

 

would an alternator from a 2001 Ford Expedition with a 5.4L v8 fit my 7.5L motor?

 

No you need a 7" 180* alternator. They are from 93-99 Taurus's, 93-98 windstar's, some year continentals and 94-96 v6 mustangs. It should look like this:

 

I'm willing to bet the '97-'01 3G in the Expy has that funky two leg mount.
If so, that wouldn't fit your 7.5.

 

Yes it does:

 

Mod motors use a completely different mount.

There was a 3G swap thread last year where someone didn't know until they had them side by side.

I'm pretty sure the serpentine 4.9 use the 8.25" ear mount.

 

Well here's what it looks like.

http://i196.photobucket.com/albums/a...e/IMG_0317.jpg

http://i196.photobucket.com/albums/a...e/IMG_0315.jpg

It's a 270 amp mechman he's selling for $275.00. I was gonna jump on it if it fits. I emailed him but he doesn't know.

Here are the specs from the actual web site btw: http://www.mechmanhighoutputalternat...2d8/97%252d01/

I've emailed them and asked straight up. Why beat around the bush. May not answer since it's taking money out of their pocket but can't ever hurt to ask.

 

That's not going to fit.

And it's a 4G...

 

What's the difference between a 4g and 3g, I don't understand that part? What does it mean?

 

Well I'm no expert but that doesn't even look like a 3G. And I'm not 100% on the 7" or 8.25" era spacing... I read somewhere on this forum it was 7"...

 

Sorry, it's a 6G.
It means 1st Generation, 2nd generation, etc...
1G's had an external voltage regulator that mounted in the engine compartment, and an external fan, with studs to connect the wires.
2G's had an integrated voltage regulator and an external fan, with two multi-pin plugs.
3G;s had an integrated voltage regulator and an internal fan, with one multi-pin plug and one stud.

The mounts still won't fit your 7.5.

 

ok thanks guys!

 

So this will work then?

Here's one on ebay, if I don't have time to get to a yard.

FORD Mustang Alternator 94 95 96 97 98 99 00 240 Amp on eBay!