Early SI Alternator Upgrade - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum

Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Electrical
User Name
lost password?   |   register now

LinkBack Thread Tools
  #1 (permalink)  
Old 12-28-2008, 04:07 PM
MI2600's Avatar
Member# 3287

Last journal entry: Vortec Heads
Last photo:
Join Date: Jul 2002
Location: N. Muskegon, MI
Posts: 2,632
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Early SI Alternator Upgrade

A friend has a '72 Chevy truck he uses for plowing. His plow set-up is electric. So, he'd like to upgrade his old SI style alternator to maybe 94 amps.

I know Harbor Freight used to sell upgrade kits for the SI, but apparently not any longer.

Anyone know where an upgrade kit might be purchased? My friend wants to keep the truck original, but will go to a CS style if he has to.

Reply With Quote Quick reply to this message
Sponsored Links
  #2 (permalink)  
Old 12-28-2008, 09:41 PM
75gmck25's Avatar
Registered User
Last photo:
Join Date: Aug 2006
Location: Alexandria, VA
Posts: 2,003
Wiki Edits: 0

Thanks: 4
Thanked 108 Times in 104 Posts
I replaced the 63 amp 10si on my '75 GMC with a 94 amp 12si.. My alternator is mounted high on the passenger side, plug is clocked at 3 o'clock, and the 12si I bought was a direct replacement. I also upgraded the charge wire to 8 gauge with a 12 gauge fusible link. I ran the wire directly over from the battery positive to the alternator.

You need to find an SAE (not metric) 12si with a V-pulley (not serpentine) and it should be a very easy swap. If you can't find the right number, I think I could probably find the receipt for mine and get a parts number from it.

Reply With Quote Quick reply to this message

Recent Electrical posts with photos

Quick Reply

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Please select your insurance company (Optional)


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Early Ford Spindles fitting early Ford axles pasadenahotrod Suspension - Brakes - Steering 3 08-14-2012 07:20 PM
newbie question about early engines toddwallace Engine 12 12-17-2008 03:29 PM
A question for the solid axle, king pin, early ford spindle kind of guys... Centerline Suspension - Brakes - Steering 11 02-17-2008 03:57 PM
early hemi cuda project! need help shipping engines and building an early hemi thecountmc Hotrodders' Lounge 13 12-03-2007 05:21 PM
early comet engine swap (or early mustang) REALGONEKATT Engine 14 11-04-2007 06:15 PM

All times are GMT -6. The time now is 01:40 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.