Well, you could pick-n-pull a taurus alt AND a tempo alt, then swap the internals, put on a standard pulley and have...


...130 Amp Alternator Sweetness. :)

While you have them apart, polish the Tempo case, replace the brushes and bearings.

BTW, my Taurus alt is running flawlessly still.

Edit:

or maybe I could build you a bracket.

Why can't it ever be easy? Geezes. Ok, I am going to cancel my alternator purchase for now, and see if I can get more volts, just moving my sensing wire to a place other than the battery.

I wish I didn't have a TMIC so I could do an alt other than FD...or wasn't a sucker for A/C so I could relocate the alt. Till I'm better situated and have more experience things are what they are

Jack, today I have become a man... or well at least I get to join to league of 130 Amp Alternator Sweetness.

https://www.rx7club.com/attachment.p...1&d=1238722382

I think I had to do more work than you to get it to fit but it's in there. There was a bunch of grinding and a little bit of welding for the bracket since my initial measurements didn't work out. However, there is a small problem though. My idle is probably 600-700 and at that idle I get >13 volts. Anywhere else I get 14.0. Could it be I have a faulty alternator? or is this normal? I don't know how big the pulley is but I'd guess 2.5-3 inches.

My tempo alt is working flawlessly too :icon_tup: I think mines 90amp though I dont have a radio or anything to suck up juice with :lol:

Oh and for those that dont think the alts can handle the high revs of a rotary engine, I'm using the stock s5 alt pulley on the tempo alt, and I'm often around 5-8krpm for periods, no issues so far :)

I do get this random squeaking when its cold and my engine pops up to 3k rpm, it'll keep squealing till the rpms drop, or i can tap the throttle it stops and i can rev it abck up without squeaking, I think the belt is SLIGHTLY too loose, it only squeals for like 30seconds

I wouldn't see why it couldn't handle the higher RPMs. The insides for the tempo alt and the taurus alt is probably used in many more applications the only difference is the case.

hey yeti, you got the tempo alternator right?
Is it the 1 wire or 3 wire?

The 3 wire (The one with the plug like S5 style alt) will plug right into a S5

For s4 just do the procedure for a s5 alt in a s4

I have the taurus alternator. Also it does NOT plug in. the s5 plug has two wires and a b-terminal. and the taurus alt has three wires. and is made different.

Anyway, I guess the alternator I got was bad. because it's only 14volts where I first start the car.. once a start putting load on it goes down until the fan kicks on then it's 10-12.5 volts with fan and accessories on and maybe 13-13.5 while driving.. Any suggestions?

Ok, first of all-Nice Job on the Bracket!

Now about the voltage. None of this sounds like it is working correctly What is your idle speed? If your BAC is not working , your idle will vary thus voltage will vary at low rpms. It is normal, since the alternator is barely turning at acceptable speeds with our FC main pulley. I used a stock diameter pulley on the Taurus alt. I didn't want to over speed my alternator, so I didn't use a small pulley to essentially overdrive it-like TweakGames did originally. I knew that I might be slightly low volts at idle with everything on. For me the volts have been fine. I recently adjusted my TPS and then reset the idle speed. Now I idle at about 650rpm with all my accessories on. I do see a little lower volts than I did at 900rpm, maybe mid 13s. I am planning on resetting the idle to around 800rpm and I think this will stabilize my idle volts.

Next let's talk about the wiring: I saved the plug from the taurus and wired it into the harness of my S5. Let me see if I can get some info to help. I will take a look at mine to see if I can help you confirm that you have it in right.

Wiring:

On the Taurus plug there are 3 wires. See the Picture attached.

The middle wire is attached to a plug that loops back into the alternator. It should have a plug as pictured.

The largest of the two wires left is the 'S' wire on the S5 alternator loom. BTW, this is also the larger of the two wires on the S5 loom.

The smaller of the wires is the 'L' terminal-this goes to the smaller wire on the S5 loom.

Do this and it should work.

Good Luck.

Oh so they have 2 wire versions, I thought the s5 alt was 3 wire

The plug has 2, and the b terminal, 3 wires. MY MISTAKE

But regardless, my tempo alt looks exactly like the fc alt minus a few changes in the casing and the inability to put the b terminal thing on so it connects a the top, how did you guys solve this?

I don't understand your question. You have 2 wires on the plug. Are those connections made?
You have 1 connection-the 'B' wire-that is the heavy charging wire. Is this what you are having trouble with? Why can't you put the original ring around the post on the new alternator, tighten it down and pull up the boot?

oh it wouldn't fit, plus the b terminal on my tempo alt is long enough to touch the intake mani (on a s5)

doesnt bother me though

Yeah, I have mine wired the exact same but I didn't cut my harness (spades are in the s5 connector) I wanted to the able to undo anything I did.

I think I may have figured out my problem.. I think perhaps the b terminal isn't making a solid connection. and/or my battery is weak from my old s5 alt. I'm also guessing that either heat is hurting the alt or when the taurus fan kicks on it's really sucking the power right out of it. Pretty much everything is fine until the fan comes along but it's really starts to take the car down to running off the battery after a while of running.

My B-terminal wires are still the stock 12 or 10 gauge wires.. I'm going to have to replace the wires with 4 gauge or just piggy back it.

My alternator could be bad for all I know. it came off a taurus wagon with about 150k miles on it. My junkyard gave me a warranty so it's just heading down there to switch it out.

Well, mine came off a 150-160k miler as well. Check your connections. I saved my plug for the S5 alt-I left it plugged into the alt and put it on the shelf in reserve.

Check your connections. Your B wire should be pretty thick-it maybe 4 ga already. BTW, you can also take that alt to Autozone or Orielly's and they will put it on the machine for you and test it for free.

with any of these alts did they share the same S4 or S5 pulley, i have a gilmer pulley and need a better alt.. and grinding the pulley is something i dont really want to do but the fan is pulling so much power..

Maybe you could get your amp re-wrapped?

Thats what I did, stock fc alt, re-wrapped to 120a. It's not 130amp, but it gets the job done.

Works well so far, no worries.

No, the S4/5 alt have the same shaft diameters but all the other alts discussed, Taurus, Tempo, S6 have larger diameter shafts.

You are going to either bore your gilmer or have your S5 rewound.

Good Luck.

I just wanted to add to this. I've been researching for hours just trying to find out the best route to go with upgrading the alternator and keeping cost reasonable. To make a long story short, I am favoring the 3G alternator (the alternator that jackhild59 is using). It's borderline, but the large frame version (the one he is using) can handle a max of 15,000 rpms at the alternator shaft. Now, to calculate if you can use this particular alternator safely, you need to use this simple formula:
Alternator RPM = Engine RPM x Crank Pulley Diameter ÷ Alt Pulley Diameter
Now, in my given circumstance, my main pulley is 4.5" in diameter and my alt. pulley is 2.6" in diameter which gives me a 1.73:1 ratio. So, with my ratio, I will be spinning that large frame 3G alternator at 14,711 rpms @ 8,500 engine rpms (but 15,570 rpms @ 9000 engine rpms!).
It's cutting it close, but it's still within the limits when you're bouncing off the rev limiter :)
(unless your main pulley is too big and your alt. pulley is too small, then you might have some haphazard problems...)

Btw, here's a site that sells these alternators new in different configurations, including choosing which pulley setup you want (single v, double v, serpentine 6 or 8 rib).
Here are the small case 3g alt.'s but from what I have read, the spacing from end to end (bolt hole to bolt hole) is 8.25" apart as opposed to the large case 3g which is 7" apart (our stock alternators are 6.9" apart).
small case: http://www.qualitypowerauto.com/cata...Fcategory%3D45

large case: http://www.qualitypowerauto.com/cata...Fcategory%3D45

My preference is the large case 150 amp version for $145
http://www.qualitypowerauto.com/cata...Fcategory%3D45

in addition:
http://rjminjectiontech.com/?p=6
http://rjminjectiontech.com/?p=7

Already covered in Pages 1-3. You should have read instead of researched.:)

Pretty much covered on page 3-5, you simply found another supplier than the one posted earlier. Researching for hours?

I did read it through (one of the 1st threads I found) but I wanted to add a few things for those who are searching.
I originally dismissed it because brand new it's $185 (around here) and I wasn't considering a junkyard one because of the high possibility of it causing AC ripple because of it having a bit of mileage on it. Just because it appears to be charging great and working right, AC ripple causes many problems (I found out the hard way). My alternator had this problem for over a year now in my '91 and I was constantly tuning because all my sensors, ecu and injectors were getting ripples in the voltage therefore causing my tuning to always change and the car never ran as smooth as it should. I found this to be the case on 2 of the 4 different cars I have tuned, including my own (using megasquirt ecu). I just found out about the AC ripple from my friend yesterday who is a technician and he explained it to me. Therefore I was searching for something a bit less expensive and was considering the ford tempo alternator which is a more direct install or a few different GM style alternators. Either way, the pulley needs to be drilled out (unless you buy a v-belt pulley for the ford alternator elsewhere that is), which is not too big of a deal to modify. I wanted to add the links because they were for new 3g alternators that can be had with the v-belt pulley for a good price. I was also worried about overrevving such a large alternator because then it would have been ruined as well as a waste of money and time, which is why I added all the stuff about the alternator rpms, the formula, etc.
Just trying to help the forum :)

The only thing you posted new is the additional vendor; The crank to alt ratio 'formula' was back 3-4 pages, the revs at redline, including the max rpm that the alternator is rated.

Concerning your issue, *if* you have a voltage ripple, it's likely your alternator has a diode failing. A rebuild or any new alternator will fix this.

The other possibility is that you need to clean your battery cables :rolleyes: (increased circuit impedance).

How did you determine that you have voltage ripple? Have you had the car on a scope, or is this voltage ripple still in the theory/investigative stage? I wouldn't jump into a fix until you have diagnosed the problem electronically.

You can measure voltage ripple with a capacitor and a voltmeter set to A-C. Put the cap in series on the positive lead. If you have a ripple, you can now measure it.

Good Luck!