CELEBRATING 20 YEARS!

The sense circuit (when used) is intended to be a remote sense of the voltage at the battery, not a local sense of the alternator output. I haven't looked into the details of the sense circuit, but I presume it is a high impedance input, meaning the voltage drop from the sense line is almost nothing. That way the voltage at the battery is what the sense circuit sees at the sense input to alternator. If sense was measured at the alternator battery output, the voltage drop (IR loss for those who understand electrical stuff) across the battery cable would not be taken into account. By having a remote sense, the length and gage of cable between alternator and battery (cable resistance), and the amount of current being drawn through that cable are irrelevant. The alternator supplies whatever power is required to keep the battery within the specified voltage range, as sensed remotely.

Ok guys I have just left the yard and picked up 2 105 amp CS altenators. I used the first page as a guide and I got one off of an Impala/Caprice and the other one off of a Lumina Van. Here is where my problem lies. My car doesnt have a plug on the car, instead it has a wire bolted to the lug on the back that bolts to the battery and also a small wire that's clipped into terminal 2 and it also is bolted to the lug on the back. Help!!! What do I need to do???

I know it sounds confusing but I looked at the original setup again and that's how it is. The funny thing is my voltage guage works, it actually saved me once. The car was wired like this when I bought it over 7 years ago.

I see quite a few people are having problems installing the CS alternator using the factory bracket. I understand if you want to keep the stock look but if you don't, head to your hardware store and pick up a turnbuckle (I think that's what they're called. Used for adjusting fence doors, etc.) It makes tightening the belt very easy and it looks pretty decent. It's cheap and easy to install. I just put in a CS alt because my electric fans put a bit of load on my electrical system. It's a 140 amp from an LT1 Trans Am engine. I picked up the EC82 conversion harness from my local NAPA. Works great!

my alternator went yesterday and i had this problem. tomorrow i'm going to try and find one of these:]

Just came back from NAPA and the dealership and found the Delco and GM numbers listed at the beginning of this thread do not work anymore. NAPA could not cross reference the listed numbers. I did try a large electrical parts and service for automotive here in Seattle Washington and found what I needed. The company name is Romaine Electric. Their part numbers are 50-1243I for cars with a gauge and 50-1243L for cars equipped with an idiot light.

I gave Napa the part number 'EC82' and they pulled it right up. Good job finding alternate pn's, though.

The wire harnesese are also available at the bottom of the page on this link:

http://www.alternatorparts.com/CS-144_Special_offer.htm

I was wondering why everyone is converting and forcing the original CS144 alternators in when this is available. Its a one wire conversion and ut seems to fit like stock.

http://www.jegs.com/i/JEGS/555/10123/10002/-1

Because I paid $20 for the working alternator with 30-day warranty and then another $20 for the adapter harness through NAPA. And in my opinion, there wasnt any forcing. Only modification I did was open up the groove in the bracket for adjustment some so the bolt I used would fit and slide back and forth for belt tension. Everything thing else fit great, I just installed the upper bracket loosely before dropping the alternator in and then tightened everything up. It wont fit correctly with everything already tight.

Can I hook these up to an aftermarket volt gauge. I cannot find my alternator wires. Help!!! I am ready to do this swap I've been holding off too long. I've already bought the adapter from napa.

Just a heads up, I have a 84 MC SS. I did the upgrade to a 140 amp with adapter EC82 from Napa and everything bolted right up no mods to anything.. They only thing i needed was a 3/8" nut,bolt,washer and locking washer from OSH. Everything costs me $100 out the door.. took about 30min to do everything

This is a great writeup...I've done this swap on two vehicle one without the resistor and the alt works great but on the second vehicle.the alt refuses to charge the batt and I've been racking my brains to figure out the problem I even took the dash apart to see if the alt wiring (brown) was some how cross from the alt to the fuse panel to the gauge but everything checks out so I think ill try the online resistor and see if that solves my problem.... Thanks for the info hope tis works for me

Ok ..this write is great ....but I have a small problem my alt refuses to charge the battery I've read and tried every conceiveble wiring but the one more coming is alt wire to L terminal and batt terminal to battery and I've even put a resistor inline on the brown wire ...still no charge ...battery fully charged recharged alt
check rechecked all good what I get is starts runs reads 12.5v electric fans comes on drops to 8 or 9v switches of voltage goes up then slowly begins to drop to 6.5v approx. 6.5v and stays there disconnect battery overnite check the next day it reads 10.5-11v but won't crank engine check all wiring no breaks even did a direct wiring from starter and alt just for charging ....any idea what I'm missing

Another source for these alternators is out of 96-98 Buick Le-sabres. It has a extra mounting point on it that could be possibly used for mounting or cut off.
The Le-sabres also have the metal fan for a more original look.

I found the adapter connectors at other auto parts store for various prices:
Autozone- P/N 817-$32.99
Advance Auto Parts- P/N 84731-$21.79

For the top bolt i used a wing nut. the wing hits the bracket and keeps it from turning while you tighten the bolt down

I've been using both the CS130 alternators for years myself and another option is a 5.25" case size (which is the same as stock btw) from a 1988 Olds Firenza with the FI 2.0 4 cyl. It's rated at 105 amps and it fits a stock alt. bracket with no mods needed other than a pulley swap and the EC82 adapter. I just put one in my father-in-laws 70 Monte and did away with his crap externally regulated charging system. His had idiot lights so it was as easy as jumpering the regulator harness, soldering in the brown wire without a resistor and looping back the 10-gauge lead to the charge post-BAM done! If you opr for a turnbuckle style bracket on a gbody though you better be aware of the need for a rear support for the alternator case-using the lower bolt inthe head and the top only securing to the water pump ear is not enough support....high HP motors will have enough torque to twist and break the alternator housing. My advice is to go with a serpentine swap altogether and kill about 6 birds with 1 stone!

NEWS FLASH!!!!!!!!!!!!!!

On Rockauto .com: look up Dorman P/N 84731

This is the SI to CS adapter harness.

It is only: $9.06!!!!!!!!!!!!!

looking at the adapter from RockAuto, Advance Autoparts, and Autozone, they don't seem to have the required resistor like the one from Napa has. Just a observation. Would it be a issue to just install a resistor inline.

ok i made a error in my rush to post prices on the other connectors, I neglected to look closely. On the adapter from RockAuto, Advance and Autozone the pins in the connector on the CS side are wrong. NAPA one has them in the correct spots (1 and 3 position) but the others don't (1 and 2 position).

If anyone is looking for the SI to CS harness I have a used one available, if interested PM me for more info.

Great guide. I just finished doing this swap last night on my 85. I ordered a replacement alternator for a 96 impala. I used the napa harness EC82, and swapped pulleys over from Mr. gasket kit #6808($20). I was able to retain the stock bracket by loosening one of the bracket bolts and adjusting with a mallet. Everything bolted in and aligned without issue.

Had my alternator rebuilt but having low voltage at idle. I'm thinking the previous owner may have done an underdrive crank pulley. Does anyone know what the OEM diameter of the crank pulley is. (Turns the fan and alternator only.)

If you are tired of having someone hold the alternator while you tighten the belt, you can tap it using 7/16 tap, either fine or coarse. I used 7/16-20x3/4 bolt and it's holding fine. You probably have to grind the bolt slot for the bracket little wider if you're using the stock bracket. I used both file and Dremel, and only took about 15 minute (maybe little less) to make the slot bigger. Just make sure you do it for the length of the slot so you won't have any trouble in the future when you have to go beyond where you have the bolt right now.