Alternator question
Thread Starter
Intermediate
Joined: Dec 2012
Posts: 30
Likes: 0
Alternator question
Guys,
I was thinking of changing my alternator for my 68 Vette (mostly for looks), but I do have two questions:
1) Will going from the stock alternator (63 amp) to a 100 amp damage my car? Will it benefit it (e.g. internal regulator)?
2) What type of pulley style does the early C3 have--V-Belt or Serpentine?
Thanks,
I was thinking of changing my alternator for my 68 Vette (mostly for looks), but I do have two questions:
1) Will going from the stock alternator (63 amp) to a 100 amp damage my car? Will it benefit it (e.g. internal regulator)?
2) What type of pulley style does the early C3 have--V-Belt or Serpentine?
Thanks,
Le Mans Master
Joined: May 2007
Posts: 5,009
Likes: 1,116
From: North tonawanda NY
100 amp usually won't last as long because of the higher amount of heat generated.(also many of them are of poor quality from overseas)..This is one of the reasons gm changed the housings on the stock higher output housings for more ventilation ...you can buy a 65-85 amp chrome alternator for the same price as those cheap 100amp ones.... I bought just the chrome case and fan/pulley kit and transferred the guts from my old alternator to the new case.... there are little magnets called "brushes" that wear down and are cheap to change at this point.... they are usually what fails and most don't realise that you can get them for like $10 at any auto supply store and repair your alternator with basic tools.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Guys,
I was thinking of changing my alternator for my 68 Vette (mostly for looks), but I do have two questions:
1) Will going from the stock alternator (63 amp) to a 100 amp damage my car? Will it benefit it (e.g. internal regulator)?
2) What type of pulley style does the early C3 have--V-Belt or Serpentine?
Thanks,
I was thinking of changing my alternator for my 68 Vette (mostly for looks), but I do have two questions:
1) Will going from the stock alternator (63 amp) to a 100 amp damage my car? Will it benefit it (e.g. internal regulator)?
2) What type of pulley style does the early C3 have--V-Belt or Serpentine?
Thanks,
Race Director
Joined: Jul 2001
Posts: 15,892
Likes: 42
'68 alternators have an external regulator. Most likely the new one will have an internal regulator. You will need to modify the wiring to accommodate this.
Unless you NEED the extra amps, stick with the stock unit.
Unless you NEED the extra amps, stick with the stock unit.
4th Gear
Joined: Jun 2013
Posts: 4
Likes: 0
I had the same question..
I have a'72 454 with 37 amp stock unit (internal R)
I recently added a MSD box and twin Spal electric fans
Was thinking of going to a 80 amp alternator.
I know in '72 the wiring is Alt to starter......would I have
to upgrade the wiring as well ? Thanks...
I have a'72 454 with 37 amp stock unit (internal R)
I recently added a MSD box and twin Spal electric fans
Was thinking of going to a 80 amp alternator.
I know in '72 the wiring is Alt to starter......would I have
to upgrade the wiring as well ? Thanks...
Advanced
Joined: Aug 2024
Posts: 53
Likes: 16
As has been mentioned, the extra current is only needed if you add significant new loads. Check the current requirements for the fans and ignition. If the total is less than 10 amps, probably don't need the extra amps, If you want to run an inverter to provide 120v AC or maybe a very high power sound system you might need a a lot more current,
As for wire size, the wire from the alternator might need to be larger. For an 80 amp alternator, I'd use a #6. At 80 amps there would be about a tenth of a volt drop for each foot of cable. If you used a #8 the drop would be close to double. I would want to keep the voltage drop under 1/2 volt.
As for wire size, the wire from the alternator might need to be larger. For an 80 amp alternator, I'd use a #6. At 80 amps there would be about a tenth of a volt drop for each foot of cable. If you used a #8 the drop would be close to double. I would want to keep the voltage drop under 1/2 volt.
