I am planning on going with some kind of electric fan in the future; hence the need to upgrade the alternator.  First off let me say a couple things. Do not even attempt this upgrade unless you have the proper 3G field connector plug and make sure that your parts house has more than one alternator in stock!  The first alternator that I installed was bad (a bad front bearing caused the case to superheat), so I essentially had to do the job twice. Also, remember that you are doing this at your own risk.  I am not an professional in the automotive field, just one enthusiast trying to help another. I cannot be responsible for your actions, results, etc.  YMMV!

Before you get started, you might want to have the following on hand:
- 3/8" x 2"Bolt and nut.
- 2 #10 or equivalent ring lugs.
- 3/8" x 6.5" bolt and nut OR: a 7/16-14 x 4" bolt to mount the alternator.
- 1/4" Shrink tubing.
- 3G alternator field connector pigtail plug. (the one with the white wire in the first picture)
- SN-95 Alternator pulley, or re-use your Fox-3 alternator pulley (with minor modification)
- A new alternator belt if you choose to use the SN-95 pulley. See the table below.
 

1) The first step is to remove your old alternator by first taking off the accessory belt and the bolts that hold the alternator down. Note: If you are lucky, you didn't install the 3/8" x 6.5" alternator bolt as described in the Vortech instruction manual. The way that they install it is from what I can tell, backwards, which means removing the blower bracket AND the Vortech supplied cast aluminum accessory bracket from the block! This is a huge PITA, so with the help of the SawzAll (Man's best friend!), I simply cut the bolt head off and slid the remains out the front.

2) It will be necessary to grind down one of the dowel bosses on the smog pump to allow clearance for the larger alternator (A). I had to grind mine down about 1/8" with an air die grinder. This is not very difficult and should go quickly.

A. Clearance your smog pump here. B. Drill, ream or grind to 7/16" for larger bolt. C. Here are the 7/16-14 threads that are not used with the kit's 3/8 alternator mounting bolt. D. This is the location of the original 3/8" alternator mounting bolt, installed on the bracket before the bracket is bolted to the block.

3) Test fit the alternator.  It is a little difficult to slide the alternator between the cast bracket and the blower bracket the first couple times.  A rubber mallet will assist.

4) It is decision time again.  I initially chose to run the alternator with my stock Fox-3 alternator pulley and later changed to a SN-95 pulley, which was far larger in diameter. The reason I did this is that I felt that the Fox-3 pulley might over spin the alternator and that the SN-95 pulley was designed for this alternator.  If you choose to go with the SN-95 pulley, you will have to get a longer accessory belt, which of course means removing the blower belt, etc....  Should you choose to install the Fox-3 pulley on the alternator, you may find that once the pulley is impacted on, it will rub on the aluminum case of the alternator.  To solve this, I simply filed and sanded down the interfering area.

5) Once you've decided on what pulley you will use, you will need an impact wrench (either electric or air) to remove the nut that retains the pulley to the armature.  If you don't have one, you can usually ask a shop mechanic to swap pulleys for you.

6) Once the alternator passes the test fit, it is time to decide how you want to mount it.  Remember the bolt that I cut to get the old alternator out?  You can get a replacement bolt, trim it to length and install a nut on the back side of the cast bracket, or  as an alternative, I decided to use a 7/16-14 x 4" bolt and utilize the threaded boss that was unused on the cast Vortech bracket.  It was unused because the bolt that came with the kit was smaller (3/8").  If you decide to go this route, you must ream the blower bracket alternator hole to accommodate the larger 7/16 hole. I performed this modification with a hand reamer and a Dremel tool.  Once this is done, simply test fit the new bolt with a little oil and thread it into the bracket.

7) Now the hard part is over and it's time for the electrical work.  Please keep in mind that on the stock alternator there are two molded three pin connectors.  The regulator connector is the one with the small wires and it is left alone; you simply plug it into the new alternator.  The one we want to cut is the one with the two heavy wires (black with a yellow tracer) and a smaller tan colored wire.  Cut off the old alternator plug very close to the old connector that you are discarding.  If it is done this way, it is not necessary to extend any wires. You will notice that the new alternator uses a good 'ole fashioned binding post to deliver it's output to the electrical system.  What I did was obtained two suitable crimp lugs and crimped and soldered them to the two black wires, covering them with a piece of shrink tubing to avoid shorts.

8) At this point, you should have only one wire that is not connected.  This wire goes to the stator terminal on the new alternator.  One note about the stator terminal, it is very fragile! Do not attempt to use a standard spade lug to attach to this terminal, it will bend and possibly break off rendering your new alternator useless!  I obtained the correct alternator plug from an alternator shop for about $5.  Simply splice the tan stator wire to the new gray stator plug, solder and cover with shrink tubing. Snap the gray stator connector into the alternator, observing the location of the key.

9) Install the belt that you chose in step 4.

10) Check to make sure that all bolts are tight, and all electrical connections are solid and well insulated. Also ensure that there is ample clearance between the idler pulley and the water pump pulley and that the belt is properly seated.  If you installed the SN-95 pulley on the alternator, you may want to wait until after you test-fire the engine to re-install the blower belt after you are sure that the belt length is correct.

11) Once you test fire the engine, watch the voltmeter on the instrument cluster.  It should be reading about horizontal at idle.  As you turn on accessories, the meter will sink and then return to horizontal if the engine rpm's are brought up. If your gauge is acting similar, congratulations on a job well done!

Copyright 1999, Steve Kent.