EFI alternator question

[jeremy5780]

Getting ready to install EFI on my AMC 258 i6 / 4.2l CJ7 and I would like to get away from the single wire 64-68 amp alternator I have now. I do run a/c a winch and extra lighting. Which alternator should I go with and how do you wire the extra wires?

 

[Torxhead]

If you are currently using the oem type cast aluminum alternator mount, a 94 amp 12 si alternator will bolt right in. These are available rebuilt from an auto parts outfit. That is what I recently installed on my AMC 258 i6 / 4.2l . The largest alternator the later CJs came with was a 78 amp. I got mine from the Auto Zone Duralast series. As far as the wiring goes, the oem method was not all that great. The main charge wire, which is the insulated post in the rear of the alternator can go to the battery side of the starter solenoid. I use a #6 wire with a #12 fusible link. Then there is the #2 location on the alternator which is for the sense wire which I use a #14 wire to run to the hot line on the gas gauge with another fusible link. The #1 alternator wire is called the excite wire which is a resistance wire N.A.P.A. p/n ICR22 comes from the union of the ignition coil positive wire and the red w/tracer wire from the starter solenoid and another red w/tracer wire from the ignition module. The sense and excite wires will need a special plug which and auto parts store should have. A CJ wiring schematic will lay it out for you in the oem style. I would also advise hooking up a ground wire from the battery negative to the alternator housing.

 

[jeremy5780]

Can you help me with this 94 amp 12 si alternator do you have a part number or something. Also would this alternator give me the amperage at low RPM's to power the Electronic Fuel Injection?

 

[jeremy5780]

My current alternator is working fine on my jeep and the only reason for my concern is the EFI kit I'm going to be putting on my AMC 258 i6 / 4.2l frowns on the single wire alternators. But after adding up the amperage my jeep would use with the added EFI I'm only at 60-65 amp's needed. Just curious what I should do or curious what any of you running the upgraded EFI did to boost or leave your alternators alone.

 

[hole]

A CS130 is a bolt it upgrade, the CS144 requires opening up the mount 1/2" +/- to accommodate the bigger housing. Adapter plug is available at Napa and the required diode is available at Radioshack or similar store. Your FI likes the CS series alternator over an SI

 

[hole]

https://www.google.com/url?q=https:...ds-cse&usg=AFQjCNFrThTu2qaZzSj-kxR0obgeEWlVKg
This is my original post when I did mine, it has a link to the orininal post from Jeephammer(Teamrush)

 

[yellow85cj]

You can go to a CS 130 or CS 144 alternator from mid 90's GM cars. The CS does put out more at low rpm's. They are rated at 105 to 140 amps.

You would need to go to a larger charge wire and fusible link or replace the fusible link with a Midi or Mega fuse and holder as the Painless harnesses do.

AC delco part # PT2145 pig tail to adapt the alt plug (it has a built in resistor
that the CS alt requires. Think I paid $15 for mine.

You will probably need to clock the CS alt, but that is minor and very easy to do.

Most will fit in the stock bracket.

 

[Torxhead]

This is what I installed:Duralast Alternator DL7194-6-12 - Read Reviews on Duralast #DL7194-6-12. The older 12SI alternator does start to charge a bit higher on the rpms, the efi systems have a higher idle speed also. The newer CS units were designed for the efi systems and would be a better bet. The issue with the CS that I had was the rear hold down bolt would not clock correctly to fit and would some modifying. The SI bolts are metric also. I would suggest a big battery and cables in that system also.

 

[Lumpy Grits]

You never want to run more than 80% of your alternator's capacity for any length of time. Alternators get hot......
When you have the heater motor and wipers going, along with headlights. That's a bunch of amps be'n used. Then add in EFI and it's load demands.

LG

 

[jeremy5780]

Thanks everyone, I ordered CARQUEST Alternator - Remanufactured - 105 Amps
Part No 7888-3A got it for $67.99 shipped. I also got the wire connector that converts it to my current wiring plug with the built in resistor. I plan to upgrade the alternator wiring to a thicker 8 gauge. I just want to thank everyone for there help

 

[Lumpy Grits]

As a precaution, for when you install.
Disco the POS(+) battery lead, at the battery.
Good luck
LG

 

[yellow85cj]

Don't forget to order some 12ga fusible link. If you look at the alt wire connection at the starter solenoid end, you will see a short piece of generally black wire. That is the fusible link. When you change to the 8 gauge alt charge wire, you will need fusible link wire 4 gauges smaller, hence the 12 gauge fusible link.

And as Torx recommended, a chunk of cable from the alt ground bolt (or threaded hole that you supply the bolt for to ground the alt to block. Should be an empty 5/16" or 3/8" threaded hole in the block very close to the alt.

And some ring terminals or lugs for both ends,and the alt ground if you do it, butt connectors for the fuse link to 8ga. and sense wires.

There's nothing worse than having to go to the parts store or go back to the computer to order parts when you are in the middle of a project

 

[jeremy5780]

Alternator is in, it was a pretty straight forward install. Putting out a little over 14 volts and working good, now to see how it holds up to all my electrical demands!