Low Mount Alternator Bracket
This is for short water pump only!!
This is the low mount alternator bracket from Modern Performance in California. I purchased this on the premise that absolutely no modifications need to be completed in order for this to work in a Chevy II. I must say, Rudy at Modern really did his homework on this one! This thing fits with absolutely no problems with clearance! What you see in the picture is what you get in the bag when it is delivered to your door. In my opinion, this is a very impressive piece. All mounting hardware is Grade 8, and the bracket is very nicely cut from 1/2" solid steel. I opted for the black coating at a standard cost of $55.00 plus shipping. A chrome version is available for $85.00. In the following, I am going to walk you through the installation of this bracket on a SBC using a 120 Amp CS130 internally regulated alternator. If you have a 10SI alternator, it will fit as well.
As you can see by the pics, this could not be any more simple of a setup.
1.) If you already have some type of alternator mounting bracket, remove you setup first! Don't forget to remove the negative battery wire from the battery!!!!
2.) Find the 2 bolt holes drilled in your block at the lower right corner as viewed from the front of the car. If there is a bolt in the hole already, remove it.
3.) Reference the picture above as to how the bracket mounts. You want to make sure that the slotted hole utilizes the lowest bolt hole in the block. This slotted hole gives you your belt tension adjustment capability.
4.) Install the 2 provided 1" long bolts in the two holes in the block, make sure you use the provided lock washers!
For demonstration purposes, I show the installation of the alternator off the car, this will give you a better idea of how it mounts, and allows me to show different views!
5.) Below is a pic that shows the alternator in the bracket, notice it fits nice and tight!
6.) The CS130 Alternator was designed for use with a serpentine belt system, if you have serpentine on your car, you can press on, if not, you must change the pulley and fan to the earlier model "V" belt.
7.) Simply remove the serpentine pulley. I suggest you use an impact gun, make it an easy chore. Install your "V" belt pulley with fan, and tighten the nut! With the early model pulley installed, you can see there is still plenty of clearance between the alternator body and the fan blades.
8.) Now we must install the alternator in the car. This is very straight forward, just slide the the provided bolts through the front ears of the alternator, install the spacer, install the nuts, and you are done.
9.) Reference steps 2-4 if you have not already attached the bracket to the engine.
10.) Once finished your setup should look like the pics below.
11.) Next, we need to wire this little beast up.
12.) You are going to need a connector to fit the stock plug on the alternator. You have 3 choices here.
Note: If you already have a 10SI alternator plug on your wiring harness, the 2 following AC Delco adapter will plug directly into your harness! If you have an older model alternator with the external regulator, you may use the 2 AC Delco connectors, however you will have to cut the 10SI plug off the the adapter and wire it directly into your harness.
1.) Retain the Idiot light--Use AC Delco adapter part # 8077. The idiot light provides resistance to the alternator on the "L" pin. This will excite the alternator into operation. You must have at least 35 ohms of resistance on this wire, and no more than 800 ohms. You idiot light will operate as normal. NOTE: if your idiot light burns out, and the resistance value of the line drops to "open", theoretically, the alternator will not excite, and will not charge!
2.)No Idiot light---Use AC Delco adapter part #8078. This connector has the proper amount of resistance built into it so that the alternator properly excites and charges. You will not have use of the idiot light!
3.) Idiot light without AC Delco connector--- Most alternator/Generator shops have generic connectors with either 3 or 4 wires on them. These connectors plug directly into the CS130 alternator. The wires are as follows:
"L" terminal--Used to excite the alternator using the idiot light as a source of resistance, connect to your stock idiot light wire.
"F" terminal--NOT USED---cap this wire off
"P" terminal--NOT USED---cap this wire off--Some generic plugs do not have this wire!
"S" terminal--Large diameter red wire used to provide power to the wiring fuse box.
For 62-67, Wrap the "S" wire around and attach to the "BAT" terminal on the rear of the unit. Or, if you choose, you may cap this wire. Its original design was to feed the fuse box, then a separate wire was run from the "BAT" terminal to charge the battery.
13.) My wiring harness had already been modified by me to get rid of all the external voltage regulator wires. I retained the Idiot light wire in my harness, and subsequently used it to excite the alternator.
14.) Use the diagrams below to help wire the alternator for your application. (Generic Connector) The Purple wire represents how a stock alternator is wired in a 62-67 with the output going to the horn relay first, then to the battery. The Green dashed wire is an alternate method of wiring this alternator, but dont forget, you still have to bring power back to the horn relay in order to get power to the fuse panel (assuming you are using a stock wiring harness). The Blue dashed wire is another alternate wiring method utilizing the starter solenoid .
AC Delco Plug: Purple dashed wire is optional. Green Wire is the preferred method, as the adapter will provide power to the main harness. The dashed black line is an alternate method to alternator output utilizing the starter solenoid.
15.) After wiring my connector utilizing the generic plug, it looks like this.
16.) At this point, plug your newly wired connector into the alternator.
17.) Install your alternator belt. Note: If you are using stock size pulleys, use "Gates" belt # 7430. It is a ribbed "V" Belt.
18.) Adjust your belt tension by loosening the bottom bolt on the mount (slotted hole). Set tension, and tighten bolt.
19.) Hook up all cables......Enjoy your new high output alternator!