Alternator
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
140 is nice to have but if you dont run electric fans, big stereos, disco lights then you dont really need it....I run like 100amp firebird alt on my 69 with electric fans etc and it was fine....but if you need to replace get the 140 and have more on tap.....
Drifting
Joined: Mar 2011
Posts: 1,886
Likes: 9
The output of the factory alternator for a 1972 was very low, compared to what we see today in new cars. Something like 37 amps without AC, and 61 amps with AC.
If you install a much more powerful alternator, you may need to do a bit of rewiring.
If you install a much more powerful alternator, you may need to do a bit of rewiring.
Race Director
Joined: Mar 2003
Posts: 11,608
Likes: 780
From: Eustis ( Area 51 Bat Cave ) Fl
Yike!!!! I forget the guys who do not mod are stuck with a rather dinky charging wire.....
Race Director
Joined: Jul 2001
Posts: 15,892
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Melting Slicks
Joined: Oct 2007
Posts: 2,310
Likes: 9
From: KB7TIF Ville NV
I dont know your situation, but I put a 160 amp alt in mine all I run is a 18 amp fan ect and my 60 amp would start to fall off in charging capacity as the engine got hot. 160 amp changed that completely and would not run another stock on my c-3. Voltage stays more constant, for a stock set up the original may be fine.
I have a rebuilt 60 amp with about 200 miles on it free for shipping charge.
74.
2026 Loser of the Year
Joined: Sep 2013
Posts: 36,607
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From: New Or-leens Loo-z-anna
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The output of the alternator MUST not exceed the amperage capacity of the wiring in the car. Otherwise, an inadvertently drained battery will call on the alternator to send max power to recharge it...and the fusible links will become toasty... 
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Pro
Joined: Jul 2010
Posts: 545
Likes: 0
From: Jacksonville Fl
My every first oops. The fusiable did not just blow apart it when thermal melt down. It was at nite and there was a red glow under thr car. Boy im not making that mistake again.
Race Director
Joined: Mar 2006
Posts: 14,112
Likes: 28
From: Florida
I dont know your situation, but I put a 160 amp alt in mine all I run is a 18 amp fan ect and my 60 amp would start to fall off in charging capacity as the engine got hot. 160 amp changed that completely and would not run another stock on my c-3. Voltage stays more constant, for a stock set up the original may be fine.
I have a rebuilt 60 amp with about 200 miles on it free for shipping charge.
74.
I have a rebuilt 60 amp with about 200 miles on it free for shipping charge.
74.
Melting Slicks
Joined: Oct 2007
Posts: 2,310
Likes: 9
From: KB7TIF Ville NV
I have found that the wires stay cool, the voltage stays up, and I am a happy camper. Do whatever you want is up to you.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
Pro
Joined: Jul 2010
Posts: 545
Likes: 0
From: Jacksonville Fl
I have found that the wires stay cool, the voltage stays up, and I am a happy camper. Do whatever you want is up to you.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
Melting Slicks
Joined: Mar 2008
Posts: 2,023
Likes: 6
From: Austin Tx
I have found that the wires stay cool, the voltage stays up, and I am a happy camper. Do whatever you want is up to you.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
As the alternator heats up volts go down, no way around it.
The 160 has beefed up internals the voltage dose not drop.
I didnt get it because im running 2 fans A boom boom in the trunk headlights wipers tv screen, stimulation device
I dont have wipers, headlights, interior lights, heated seats, blower motors ect. and the stock alt still dropped in voltage.
The 160 alternator was a great investment. You should upgrade the charging wire to the battery.
I would only use an alternator that matches the requirements of the electronics in the car. If there is a problem with the battery charging after that, then there is something that needs to be found.
Melting Slicks
Joined: Oct 2007
Posts: 2,310
Likes: 9
From: KB7TIF Ville NV
Charging system was designed with minimal electronics, adding large electric fans was not in the designs, Im convinced on that after seeing what a difference in charging ability that high output alternator made.
So just giving you some other insights of good information for your notebook.
Although you may have a point on the resistance change in the circuits. Thats some good information.
Its pretty universally known of voltage drop vs heat in alternators. I threw the rebuilt out.
So just giving you some other insights of good information for your notebook.
Although you may have a point on the resistance change in the circuits. Thats some good information.
Its pretty universally known of voltage drop vs heat in alternators. I threw the rebuilt out.
Last edited by illenema; Jan 27, 2014 at 09:44 PM.