I just took a 20 mile test drive in my 90 Vert. I have a Taurus two-speed fan using the low speed for cooling and the high speed for A/C. The total of the requirements for running the engine, a/c clutch, high-speed Taurus fan and the interior fan were just a little too much for the stock S5 alternator. Add in lights for a night drive and the S5 alternator just wasn't enough. Now what happens when I do the stereo with two amplifiers? No, something else needed to happen.

The FD alternator, easy fit that it is, is only 100 amps. That's nice, but only 20 amps of head room over stock didn't even really bring me back to stock levels when you account for the 25 amps added from the Taurus fan, let alone a couple of large amps.

Please note that for stock use, the S5 is just fine, it does not suck. The FD does not suck just a little less. What to do? I wondered how the lowly Taurus was able to run the high current draw of the fan and the obviously higher amperage draw of power seats, sunroofs, etc. How? With a factory 130 amp alternator, that's how. Aha! And Ford made a buttload of these things, so they would be cheap cheap cheap for the man who could adapt. This was just what I needed!

So last Saturday, I tripped out to the pick-n-pull and pulled an alternator from a 1996 Taurus 3.0 OHV. I got the alternator, the harness and the entire charging wire from the alternator to the fuse box.

$20-cool! While I was there I got a couple of MarkVIII fans-one for me and one for my Porsche buddy. $65 for an alternator and two Mark VII fans, that is my idea of a back to school sale!

The Taurus alternator mount is the opposite of the S5 mount- it looks just like the mounting point on the S5 engine. So I got it home and sketched out an adapter to the factory mounting point. I fabbed a mount with some adjustments so the pulley alignment could be just right, bought some Grade 8 3/8' bolts and presto! I have the Taurus alt mounted using the factory tension adjustment to boot!


A pulley change from serpentine to v pulley and then on to the wiring.

The Taurus alt uses a 3-wire system exactly like the S5: One wire to the main fuse, one wire to the charging light on the dash and one wire to the EGI fuse.

Piece of cake.

I wired the Taurus plug into the S5 harness, plugged it in, tensioned the belt fired it up and POW!!

Not really, the only thing that happened is 14.2 volts. at idle. With the lights, A/C on high inside, the Taurus fan on high, the headlights on and the brake lights lit, the idle volts are at about 13.6, 600 rpm. Anything above 1000 rpm and I get 14 volts.

Subjectively, the Taurus alternator doesn't pull down the engine nearly as hard as the S5 did when the A/C clutch kicked in and the High-speed fan came on at the same time. With the S5 alt, the engine would drop by 200 rmp, from 600 to 400 and the car would nearly die. The volts dropped quite a bit at the same time. If all this happened when you were starting up from a stop sign or stoplight, the car would stumble. My theory is that the S5 was at the top of it's output and maybe wasn't as efficient as the Taurus alternator is. The rpm drop is minimal and the stumble is gone.

I took some pictures to illustrate the mount, the adjustability of the mount for pulley alignment and of the general look of the alt on the car, but it is late and the pics need resized to post. I am too tired and the Cowboys play tomorrow, so off to bed for now. I will post some pics. I intend to take the alternator off, clean it up (man is it dirty!) and take some more pics.

 

nice.cant wait for the pics..

also a big cowboys fan btw.. cant wait for the game

 

I like where your head is at and interested to see the end result. However, even though this is not The Lounge you cannot dangle a ******* carrot like that and not have pics

Pics or it never happened
or
Pics or GTFO

 

There's gotta be a simplier option that this...

My Cressida uses a 130A alternator.
Others have mentioned that the Maxima uses a 130A alternator.
Some Hondas (Odyssey) use 130A alternators.

I'm sure one of these uses a proper "saddle mount" which should drop right in?
I'm suspect of USA made parts. :P


-Ted

 

yea so let us know!!

plz

 

i had minne altenator rebuilt and upgraded to 120 amps simple and local shop only charged 80 bucks

 

Anybody have a pic of the stock S5 alt mounting tabs. If you guys think a Honda one will work, im currently running a 160amp Jeep Wrangler alt on my CRX. It bolted on without any work, might be a viable option.

 

Heh, heh. I checked my pictures just to make sure it really did happen. It did.

It was a very late night for me. I was too happy not to post up, but too trashed to edit the photos for the forum.

 

Ted-
I agree, there may be an simpler way, but when you see the double saddle bracket made from 1" angle x 1/8" steel, you may agree that there is not a cheaper way when you consider the millions of inexpensive Taurus alternators out there.

Pics in the next post.

 

Made from 1" angle, 1/8" stock.

 

This view of the Double Saddle Mount Bracket shows the space allowed for adjustment shims-hardened grade 8 3/8" washers.

By moving the shims one at a time from the front front to the back the alternator could be moved in +/- 3/16" increments for pulley alignment.

The same amount of space is allowed in the upper mount where the alternator mounts. Combined, there is about 3/4" adjustment in 3/16" increments. Simple effective. The pulleys are pretty much perfectly aligned.

Also note the upper saddle is extended forward to set the alternator forward, again to roughly position the alternator pulley over the waterpump pulley.

 

The new belt is only 1" longer than original.

 

Really not so complicated. If I were a machinist or had some access to a machine shop, the bracket would be easy and cheap to duplicate.

I really only spent about 30 minutes on the actual fab of the bracket, drilling the holes, bending the ears etc. and this for the first time done. I spent more time measuring, making notes, etc to design the double saddle mount than actually making it.

 

Could you estimate how much higher this alt sits compared to stock?
I'm curious about whether it would interfere with a strut tower brace.

 

I had a similiar project, I had a mazda alternator in my V8 car, I put a 130+ amp brand new alternator from a camaro in there, it was
a 20 minute swap, I got a wire harness from GM that has the resistor built in so the car does not overcharge or any of that stuff. I went with the newer style 4 wire alternator because I had read how good they are compared to one wire or 2 wire alternators, I cant seem to remember why but there was someone who had a website with incredible information on it that convinced me about it- but that link is on my work computer right now.

My guess as to why there was a mazda alternator on the car is either thats what was around, or they did not try to figure out how to wire a GM one on there.

The adaptor goes from a 4 wire to a 2 so you can either just cut the ends off and splice them to the factory wiring, or you can get the other end of the plug and wire that in, which is what I did.

Here is a picture of the wiring adaptor and alternator





here is the plug on the alternator




here is the old alternator on the car, and yes the writing on the PS pulley is now gone- along with the PS



the only picture I have of it installed.

 

Or so the wife sez

Pic of the S5 80 amp alternator sitting on top of the Taurus 130 amp alternator

 

I could have used a belt that was only 1/2" longer than stock, or even the stock belt could have been used, but I wanted the adjustment to be in the middle of the range. If you used a slightly shorter belt, the tensioner would be in the lower range and alt would be slightly lower. With the stock belt, the tensioner was at the BOTTOM of the slot.

Here is a pic with a 4' level across the strut towers covers. You look at it and determine. Let me know if another picture or measurement would help.

 

my main point was that I went from a mazda to a gm and it was a direct swap with no brackets needing to be made and basically plug and play, I now have a lifetime gurantee alternator that can dish out anything I throw at it. I also did not have to change out my belt

I also dont know about your area, but locally my alternator shops and smaller auto parts stores wont sell you a FD alternator without a core anymore. I ended up getting a brand new FD alternator for my vert from someplace online, its also lifetime gurantee and came tested at like 120amps or something.

 

That'll do, thanks.

 

So you put the GM alt on your rotary? Or you replaced the Mazda alternator on your GM V8 RX7 swap with a GM alt? I think I just got a little dizzy!

Nice vert Rob!

 

I pm'ed 4 different sellers in the FD section selling FD alternators. Only one replied and he told me that I should really just buy one at the parts store. I took that to mean that his alternator was not going to work.

I decided that I was not going to make a change of any kind for only 20 amps. Even if it 'tests at 120 amps' that doesn't upgrade the size and internals. I'm sure that most stated amperages are slightly conservative and testing would uncover that margin. Maybe if you tested your 130 amp GM it would test out at 150 or 160 amps. Interesting theory.

Anyway, with a rated 130 amp, I (and you as well) won't have any issues carrying any electrical load we throw at our cars.

We must be the charter members of the Rotary Engine 130 Amp Alternator Club!

 

that month was an expensive month for alternators for me.

I put brand new FD alternator in my rotary vert and went from a rotary alternator in my v8 car to a new GM one- it gets me dizzy as well!

both alternators came with test results, the gm one was actually putting out 150+amps.

 

My Orielly's had a new alternator tester that should have been able to print out a graph of the output of the alternator. No one, including the manager, could remember their recent training on the machine and how to get to the graph. They put in the specific model of vehicle and it tests and confirms that it met the spec of 130 amps.

Basically, it passed.

 

Nice work!
I gotta agree that the fabrication is on the simple side.
Kudos to you.

One thing that still bothers me...
With the higher redline of the 13B, cause these domestic alternators take that kinda revs?
I guess if you can update this thread regularly?
I bet the Taurus motors can't rev past 6kRPM?


-Ted

 

The pulley you have on the Taurus alternator appears to be smaller than the one on the stock unit. Have you considered the fact that you're potentially going to be spinning the Taurus alternator faster than it was designed to go? Combine that with the fact that the redline on a Taurus is likely something pitiful like 5k RPM and you could end up with little bits of copper flying through your hood when the armature explodes.