Doing the conversion from the original SI alternator to a newer CS unit seems pretty straightforward (with the splicing in of a new pigtail), assuming one has the "correct" CS unit to install.

My question is - Other than the mounting tab differences (see image below), is the clocking of the back of the alternator an issue, or can the alternator simply be taken apart and the back rotated?



Are there any other variations or differences in CS130 alternators that might cause an installation problem.

The reason I ask is that I have an opportunity to buy a new/rebuilt alternator listed for a '94 Beretta/Grand Am for a good price, but I'm not sure it will actually "fit" my '86 GT.

if you get the alternator for the '88 Fiero - it has the mounts in the same place as your original alternator
if you can - get the 5-groove pulley, otherwise you will either need to use your original pulley

quote Originally posted by Pyrthian: if you get the alternator for the '88 Fiero ...

Pyrthian, thanks for the advice (and yes, that's the simplest solution), but it doesn't really answer my questions.

Patrick, It should be no problem to remove the three bolts that hold the case together and clock the alternator. In fact I've never seen an alt. that could not be clocked. I tried to convert mine to a CS130, but I had bought the wrong model- wrong mounting holes. Anyway, when I prepared to do the conversion, I found information online that was perfect for any alternator conversion: http://www.madelectrical.com/
There is so much information here it is just amazing. After I decided not to do my conversion, I still used some of the information here to rewire the Fiero for better electrical system performance. Check them out.

Ang, thanks for that link. Looks like lots of good info there!

So just to clarify this, as long as the CS130 alternator has the mounting tabs in the right location (12 and 6 o'clock), then clocking (rotating) the back of the alternator (and splicing in the new plug) is the only other thing I need to be aware of for the alternator to work with an '86 GT?

In other words, will a CS130 alternator (A1430) listed for a '94 Beretta work with my '86 GT as long as the mounting tabs are at 12 and 6 o'clock and I rotate the back of it to have the wiring accessing it from the correct angle?

Patrick: in the photo you posted above, the left alternator will fit a Fiero, but the right one will not. Every GM FWD car with a 60-degree V6 that I've seen (which includes the Beretta you mentioned) has the type shown on the right. In other words, it won't fit.

The '88 Fiero V6 alternator is a sure bet.

[This message has been edited by Blacktree (edited 08-25-2009).]

Yes, it SHOULD work, what you will need to do (what I failed to do), is make sure the distance BETWEEN the mounting holes (center to center) is the right dimension. That is why mine would not work - I secured the alt. with the pivot bolt, but the top bolt was 1/4 inch below the adjustment slot. If you can find a car that used a CS130 with the same center to center measurement then it will work. Mad Electrical has the information on properly wiring it up, as it will be different than wiring on the old SI style alt.

Yeup, that should work. As long as the tabs are in the right spot you can clock the case to the correct position for the Fiero. From there, the install is very straight-forward. You might want to inspect your stock alt bracket while you have it apart for cracks as well. Mine had a small crack in it so I ordered a thicker bracket from the fiero store. The cracked bracket flexes just enough to let the alt squeal, even with an underdrive and idler pulley. Heck, the idler is probably the only thing holding it together right now. After I pull the bracket off, I think I'll donate it to my casting professor as an example to use in his class of bad casting design...

I have an '86 that I'm working on getting it running right and I got it as a basket case so I never had the original alt running on it in the first place. I needed a new one so I just bought the CS130 and the pigtail off RockAuto.

I just put an 88 2.6 alternator in My 86 GT no problem! the first one I ordered was for a 4 cyl In a 2.8 box.The next one was the correct one. Make sure the pulley has 5 groves.
The wire's worked fine without rotating the case, Be sure to splice on the new end to the harness! Good luck, It is a great improvement.

You may have to switch pulleys too. This shows the difference between the 87/88 L4 and the 88 V6:




Here are the ones that directly interchange with the 88 Fiero V6:

[This message has been edited by spark1 (edited 08-25-2009).]

quote Originally posted by Blacktree: Patrick: in the photo you posted above, the left alternator will fit a Fiero, but the right one will not. Every GM FWD car with a 60-degree V6 that I've seen (which includes the Beretta you mentioned) has the type shown on the right. In other words, it won't fit.

Blacktree, you're just messing with me, aren't you?

From this thread Here, you can see that it's mentioned that the alternator on the right side is for a V6 Fiero and the one on the left is for the '87-'88 4-banger. If that isn't correct, then spark1 has some explaining to do.

So, are we at least all in agreement now that the mounting tabs need to be at the 12 and 6 o'clock positions for all V6 Fieros?

I have a fiero store bracket sitting behind me to measure Give me a sec...

Edit: Ok, so the bracket is 7 inches from the top of the mounting hole to the bottom of the adjustment ear.

On the extra groove on the pulley you can run the 6 groove just fine on a 5 groove belt. It won't hurt it any

[This message has been edited by Alibi (edited 08-26-2009).]

quote Originally posted by Alibi: Ok, so the bracket is 7 inches from the top of the mounting hole to the bottom of the adjustment ear.

That's great, but is there any way you could translate that into the distance between the centers of the two holes? When I phone the fella with the Beretta alternator, that's what he'll be measuring and what I'll have to be comparing measurements to. It's only a difference of a quarter inch between the right and "wrong" alternators, so we can't just be "close".

quote Originally posted by Alibi: On the extra groove on the pulley you can run the 6 groove just fine on a 5 groove belt. It won't hurt it any

Although there is a half inch difference in diameter. The smaller L4 pulley used on the V6 engine would be spinning a little faster. Might actually be beneficial for someone though who has an underdrive pulley on the crankshaft and the alternator isn't quite charging enough while idling.

I'm not sure on the diameter issue, but just the extra rib won't hurt anything. If the SI pulley won't swap over and/or the Beretta pulley won't work I'll mail you my pulley from my CS130 that I ordered off RockAuto. I pulled it when I installed my Dickman idler/underdrive kit so I don't need it... I also didn't bother to check and see how many ribs it had but, like I said, it shouldn't matter (I did a search and confirmed this a couple weeks ago, actually).

The hole diameter for the adjustment (lower) slot is half an inch. The upper hole (threaded) is just shy of half an inch by about an 1/8. I wish I had some calipers on me so that I could get more precise measurements but the best I can manage is a tape measure. Also bear in mind these numbers are off an aftermarket FieroStore bracket but I don't see why they would be any different from a stock bracket.

So... from my measurements center to center would be ~6.45 inches. Bear in mind the lower adjustment slot is slightly wider than the bolt used to tighten the alternator in place (to allow it to swivel for adjustment) but I doubt GM would have made CS cases with size differences in 1/10 in. increments so I think 6.5 in. center to center would be correct for a nominal value.

quote Originally posted by Alibi: I think 6.5 in. center to center would be correct for a nominal value.

Alibi, thanks very much for the info, and thanks for the pulley offer. I don't think I'll need the pulley, but I'll keep your kind offer in mind.

Did you have to use an impact gun to get the nut holding the pulley off the alternator?

No prob, if you need it just shoot me a PM. I've got it sitting in a box with some other random Fiero brackets I just conveniently had a bracket sitting a box that came in today from TFS so its no biggie on getting the dimensions either.

I did use an impact gun to get the pulley off, but it was just an electric impact so it doesn't take too much oomfp to break it loose. The big trick was getting the center shaft from spinning. To pull it, I could hold the metal external fan when I hit it with the impact and it came loose pretty well but to put it back on I had to hand tighten it first w/ a regular open end wrench while holding the center shaft steady with a T 50 (?) torx socket in the other hand. After it was tight enough, I could then use the impact gun to tighten it up again. The shaft is keyed for a 6 point allen wrench, but I didn't have one handy but the Torx socket fit snug enough to keep it still. It was awkward to do so if you have a vice or a friend to help hold it would be easier.

There are loads of '88 alternators available on ebay, but very few for the '84-'84 models.
After lots and lots of searching i found a remanufactured one, I wish now I had bought an '88 alt as they put out more amps.
The one I ended up with fitted the mounting bracket but the electrical connection was 90 degrees out, Just spliced a couple of inches of wire in to make it fit.

After a few miles my alt belt snapped, this happened twice more before I realised that my new has got the wrong pulley !
Unfortunately id scrapped the old alt with pulley attached...doh...

so the moral of the story is beware what you buy on ebay motors, car and parts dealers are notoriously dodgy at the best of times, and especially so when they are hiding behind the internet.

Im now on the hunt for an alternator pulley ;-/

quote Originally posted by Patrick: Blacktree, you're just messing with me, aren't you?

Sorry, I got it backwards. The Fiero alternator is on the right, and the Beretta one is on the left. And... it still won't fit.

I am going to transplant a '86 motor into an '88. Anyone have a diagram or photos of the splicing needed?

https://www.fiero.nl/forum/Forum2/HTML/099013.html

https://www.fiero.nl/forum/Forum2/HTML/097442.html

Those should help. IIRC, its thick wire to thick wire and brown wire to brown wire. Its very simple

Patrick, I have both the 10/12/15 SI series model & the CS model disassembled completely for a welder project I'm doing. I can take any measurements you need, as well as give you any pinout info you might want to be sure your pigtail is correct. I can also send you any hi-res pics if you need them.
For reference, my CS came out of my '85 duke coupe... If you would like, I also have both mounting brackets removed, and I can compare those side-by-side as well so you can see if you will be able to just swap a CS bracket onto your application...
Just let me know what you need.

-Paul

------------------

quote Originally posted by Blacktree: Sorry, I got it backwards. The Fiero alternator is on the right, and the Beretta one is on the left. And... it still won't fit.

Well, that remains to be seen.

I'm hoping to find out today where exactly the Beretta alternator mounting tabs are located.

Patrick, it looks like there has been a lot of traffic since I last checked in. Ok, there are a few models of CS alternator. If i remember correctly the number refers to the stator diameter in millimeters. I think there is one smaller than the CS130, and I know there is a CS144. As far as different center to center dimensions of the CS130, I don't know. I didn't find one, but that doesn't mean that it doesn't exist. You also had a question about swapping pulleys. The pulleys swap between old and new styles, the shaft diameters are the same. That part of the swap worked for me.

quote Originally posted by Ang84Indy: Ok, there are a few models of CS alternator. If i remember correctly the number refers to the stator diameter in millimeters. I think there is one smaller than the CS130, and I know there is a CS144. As far as different center to center dimensions of the CS130, I don't know. I didn't find one, but that doesn't mean that it doesn't exist.

I'm confused again. Was the alternator with the wrong dimensions that didn't work for you a CS130 or was it a different model CS alternator?

I'm just trying to determine (from what you've stated) if there are indeed CS130 alternators which have the wrong dimensions or if it's possibly just other CS alternators (such as a CS144) which would be a problem.

Ang, I hate to beat this to death, but I'm just trying to make this clear for anyone considering this swap.

quote Originally posted by Ang84Indy: ...make sure the distance BETWEEN the mounting holes (center to center) is the right dimension. That is why mine would not work - I secured the alt. with the pivot bolt, but the top bolt was 1/4 inch below the adjustment slot. If you can find a car that used a CS130 with the same center to center measurement then it will work.

The one I bought is a CS130. I don't know if there is a 130 with the right distance center to center. A CS with a larger stator will have a larger case diameter. It might be similar in size to an old SI style and be more likely to have a similar center to center measurement. I wanted a smaller case diameter than my original SI to make changing the alternator easier. Hope this clears things up.

quote Originally posted by Ang84Indy: The one I bought is a CS130. I don't know if there is a 130 with the right distance center to center. Hope this clears things up.

Heh heh, I think you've cleared it up in a roundabout sort of way. As far as I know, the recommended '88 V6 Fiero alternator is a CS130. Therefore it appears that it is indeed possible for some models of the CS130 alternator to be the wrong size to fit the factory V6 Fiero mounting bracket.

Glad we got that covered. Thanks Ang.

6.6? Cool, that is pretty close. Not bad for just eyeballing with a tape measure

Lets see here... modify a $40 bracket for a $100 alternator and possibly end up with neither working or just buying the proper alt for $100 and be done with it. I think I would just get the right alternator and be done with it. The best prices I could find was RockAuto (be sure to google for their very-commonly distributed 5% discount codes) and I believe they will also have the correct pigtail too.

The Beretta alt may be 3/10 of an inch off and I think that would be removing a good chunk of support material to get it to fit. Would it work? Probably, but knowing I had a potential weak spot in the bracket or just having something a little off would bug me after a while. Also, what would you do about replacements like going back to the correct alt but being stuck with a modified bracket?

quote Originally posted by Alibi: Lets see here... modify a $40 bracket for a $100 alternator and possibly end up with neither working or just buying the proper alt for $100 and be done with it.

The reason why I was interested in using this particular alternator was because I can get it for $20, never used.

The other option I see while looking at that last image I posted is that I could actually swing the top of the alternator to the left an inch or so and use some kind of short homemade "bridge" between the top alternator mounting tab and the factory bracket. That way nothing would be altered or damaged and it would be possible to revert back to the stock setup if necessary.

Man, I know more ways of wasting time, eh?

The CS130 was made in several different frame styles and connector clock locations. The one used on the 88 V6 was frame style “A” clock position “5". The L4 used frame style “F” clock position “9". The Beretta one appears to be a “splt G” frame style (whatever that is) with a clock position “5".

There were several other GM models that used a 100 Amp CS130 with the “A” frame and clock position “5" but with different connector pin-outs and or pulley sizes. Some of those might work if you are careful but the Beretta/Grand AM looks like a bad fit.

edit:

See http://www.acdelcotechconne...tas_alt_clock_cs.pdf

The 88 Fiero model is 321-380. You can go to the ACDelco "parts fit" http://198.208.187.182/inte.../VehiclePartFits.jsp, type in a model number and it will show which cars it will fit.

[This message has been edited by spark1 (edited 08-27-2009).]

quote Originally posted by spark1: ....but the Beretta/Grand AM looks like a bad fit.

Yeah, you're probably right. Dang it.

Anyway, I want to thank everyone for their input. Much appreciated!

Oh, so you would make a small bracket to bolt to the top mount that extends past the mount with another hole spaced properly for the alt? Yeah, that would probably work too but I'm lazy :P If you do it, more power to ya

$20 *is* a good price for a brand new alt, but if it doesn't fit right...

Thanks for the link to the pigtails!

Been a long while since I've been on, but things have happened in RL that will probably be making/allowing me to turn my Fiero back into a daily driver.

My alternator lasted me 9 years in Las Vegas, and then didn't like sitting in the CO cold for too long. So I'm considering an alt upgrade. For the past 2 days I've checked AutoZone, Checkers & Advanced AutoParts for the right alternator and pigtail. The AutoZone numbers came up discontinued at my local stores, with no availability from the vendor either. Checkers (CSK) actually had what I believe to be a correct alt:

Ultima 01-0381 105amp $90 (V-pulley)
Ultima 01-0380 100amp $90 (5-groove)

They had the 105amp and it 'looked' correct, however they did not have a pigtail for it. So I held off on getting it, for now, so I could do a bit more research.

With a request from my wife, I went to the JC Whitney site, and pulled up a '88 Fiero GT and they actually have the choices for 100a and 140a alts, new in stock! My guess is I'd still have to find a pigtail. But does anyone have any experience with the MCI alts? And would a 140a be too much for an '87 GT?