Easy Alternator Upgrade Question?
Thread Starter
Burning Brakes
Joined: Nov 2000
Posts: 948
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From: Johnston Iowa
Easy Alternator Upgrade Question?
I want to upgrade my stock alternator to 100 or 140 AMPS.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by James
I want to upgrade my stock alternator to 100 or 140 AMPS.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
Melting Slicks
Joined: Aug 2004
Posts: 2,906
Likes: 228
From: Oakbank Manitoba
Originally Posted by James
I want to upgrade my stock alternator to 100 or 140 AMPS.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
If I do not want to mess with changing around the stock wiring configuration can I just run a new thick charge wire to the battery and continue on using the stock wiring configurtion?
My plan is to switch to the MADD Electronics New System wiring configuration but I thought Initially I would run it like this if it is ok.
Melting Slicks
Joined: Nov 2001
Posts: 2,668
Likes: 43
From: Eastern US XX
Originally Posted by KENS80V
You are correct....the charge wire must be upgraded. With a 140amp alternator the appropriate charge wire should be approx. #4 gauge. I am currently upgrading my charging system to accommodate dual electric fans and fuel injection. MADD Electronics has some great reading on their website. I just bought a CS144 Delco alternator from these guys...www.alternatorparts.com. My 1980 Corvette had the heavy duty alternator (72amps) and the original charge wire back to the battery was approx. #10 gauge. The only problem I am having is how to protect this wire in case of a short. You can't get a fusible link big enough to protect a #4 gauge wire. You must use a large fuse. I am currently trying to decide how big a fuse to use. They are made by Littelfuse...called "MEGA" bolt on fuse.
Again, the MAD update (as opposed to Mothers Againsd Drunk Driving - MADD) does NOT suggest increasing the size of the CHARGE wire (10 gauge is more than adequate) - it does MOVE that wire. The 8 gauge wiring is to supply power to the accessories.
Melting Slicks
Joined: Aug 2004
Posts: 2,906
Likes: 228
From: Oakbank Manitoba
Originally Posted by pws69
Again, the MAD update (as opposed to Mothers Againsd Drunk Driving - MADD) does NOT suggest increasing the size of the CHARGE wire (10 gauge is more than adequate) - it does MOVE that wire. The 8 gauge wiring is to supply power to the accessories.
Melting Slicks
Joined: Aug 2004
Posts: 2,906
Likes: 228
From: Oakbank Manitoba
I must add that if you increase the size of the alternator and put no increased demands on it than the original charge wire will be adequate. Add dual electric fans, large stereo amps, fuel injection system etc, etc and watch that charge wire overheat and eventually fail. Hopefully the fusible link frying will not cause a fire and destroy the car. Any body else care to chime in?
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Team Owner
Joined: Jul 1999
Posts: 65,492
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From: Orange Park Florida
ASSUMING that ALL the wiring is in good shape, big assumption especially with the age and corrosiion of/under these cars....you do NOT nead to change a damn thing in the stock wiring harnesses,....theoretically...unless you got something bad of course, like that classic Molex white square connector on the a/c side firewall there the starter harness plugs into the main harness...they go bad all the time, it's not even a weathertite on the cars I have seen....
so first check the battery cables....ALL of them, engine to ground under pass side engine mount, make sure everything is clean polished steel under there, corrosiion will NOT WORK...
then all the super high amp connections for fans/etc...run a ground AND positive high current lead DIRECTLY to the alt output stud and case ground...been running my stuff like that for years....
the fusible link is fine for battery charging, ....
GENE
so first check the battery cables....ALL of them, engine to ground under pass side engine mount, make sure everything is clean polished steel under there, corrosiion will NOT WORK...
then all the super high amp connections for fans/etc...run a ground AND positive high current lead DIRECTLY to the alt output stud and case ground...been running my stuff like that for years....
the fusible link is fine for battery charging, ....
GENE
Le Mans Master
Joined: Aug 2003
Posts: 7,720
Likes: 12
From: Chattanooga TN
Originally Posted by KENS80V
.... You can't get a fusible link big enough to protect a #4 gauge wire. You must use a large fuse. I am currently trying to decide how big a fuse to use. They are made by Littelfuse...called "MEGA" bolt on fuse.
Melting Slicks
Joined: Nov 2003
Posts: 2,668
Likes: 119
From: St. Charles Mo
CI 5 & 8 Veteran
Let me chime in by saying...If you are going to re-wire the car, I definitly like the MADD single point distribution setup they discribe. However, thats no small task.
Everything Gene states is right on
with the following clarifications:
If you are installing aftermarket fuel injection with ECU computers, wire them up to the clean (no voltage spikes) power and ground The closer to the Positive and Negative Battery terminals the better, however the other end of the battery cables are large gauge and are just as good.
Adding an additional charge wire from the alt to the battery ( or the +12 starter cable) is a good thing, (especially if you add current draw from the battery,) if you recognize the need to fuse and the fact that now you have bypassed your amp meter and it will not read correctly ( if at all).
Bullshark
Everything Gene states is right on
with the following clarifications:If you are installing aftermarket fuel injection with ECU computers, wire them up to the clean (no voltage spikes) power and ground The closer to the Positive and Negative Battery terminals the better, however the other end of the battery cables are large gauge and are just as good.
Adding an additional charge wire from the alt to the battery ( or the +12 starter cable) is a good thing, (especially if you add current draw from the battery,) if you recognize the need to fuse and the fact that now you have bypassed your amp meter and it will not read correctly ( if at all).
Bullshark
Melting Slicks
Joined: Aug 2004
Posts: 2,906
Likes: 228
From: Oakbank Manitoba
Originally Posted by Bobchad
Do you run the charge wire to the battery wire at the starter or back to the battery? I thought my electrical manual showed the charge wire at the starter.
