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| | | | Joined: Dec 2014 Posts: 49 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2014 Posts: 49 | Any suggestions for an alternator on a 1954 chevy truck that has been converted to 12 v.
Thanks!
Scott M.
| | | | | Joined: Aug 2012 Posts: 1,214 Shop Shark | | Shop Shark Joined: Aug 2012 Posts: 1,214 | Just went through a similar process on my project, I decided on a GM SI series 3 wire alternator.
it has better voltage sensing capabilities over the 1 wire, but many go with the 1 wire because of it's simplicity and it does work.
If you're already wired for 3 wire that's how you should go. If not it's not hard to wire, but a 1 wire is as simple as it gets.
Good luck
Dave | | | | | Joined: Feb 2012 Posts: 70 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2012 Posts: 70 | I am curious about this as well. | | | | | Joined: Sep 2001 Posts: 29,269 Bubba - Curmudgeon | | Bubba - Curmudgeon Joined: Sep 2001 Posts: 29,269 | One of my 1954 Chevrolet pickup trucks has had a one-wire 12v alternator in it for 16+ years. It has always worked fine.
There was no need for an indicator light wire in that truck, and the alternator self-"excites" every time (due to the normal higher idle at start-up) eliminating the need for an "excitation" wire.
| | | | | Joined: Dec 2006 Posts: 1,154 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 1,154 | Only one to get Randy Rundel fifth ave. garage. With his alternator you don't need to rev the engine to get it excited . A great guy and stands by his products! Look him up on the net Fifth Ave. Garage.
Steve
| | | | | Joined: Dec 2013 Posts: 771 Former BMW Rider | | Former BMW Rider Joined: Dec 2013 Posts: 771 | scooter m., This link should provide plenty of information to help you select an alternator. Good luck, | | | | | Joined: Feb 2012 Posts: 70 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2012 Posts: 70 | What clock position works well for a stovebolt motor? I am thinking 9. | | | | | Joined: Feb 2000 Posts: 5,191 'Bolter | | 'Bolter Joined: Feb 2000 Posts: 5,191 | I have been using one wire alternators for years and years with out any problems. The normal starting rpm is enough to energize them, if not, a slight blip of the throttle will work, no high rpm is needed. Be sure to use 10 gauge or heavier wire off the back terminal.
Joe | | | | | Joined: Feb 2012 Posts: 70 Wrench Fetcher | | Wrench Fetcher Joined: Feb 2012 Posts: 70 | Based on the MadElectrical website, I think this will work for me.
12SI, 94 amp, at 3:00 (AC-DELCO # 321-266, Lester #7294-3)
Tell the auto parts counter person that “The alternator is for a 1984 High performance Chevy Camaro, with 5.0L (305G) engine, 94amp alternator
OR
12SI, 78 amp, at 3:00 (AC-DELCO #321-247, Lester #7278-3)
Tell the auto parts counter person that “The alternator is for a 1985 Pontiac Firebird, 5.0L (305H) engine, no air conditioning, H.B.L. only.” (H.B.L. = Heated Back Light–meaning rear window defroster) | | | | | Joined: Dec 2014 Posts: 49 Wrench Fetcher | | Wrench Fetcher Joined: Dec 2014 Posts: 49 | Thanks for all the suggestions.
Scott M.
| | | | | Joined: Mar 2005 Posts: 1,636 'Bolter | | 'Bolter Joined: Mar 2005 Posts: 1,636 | One wire alternators are great for what they do. But there is a reason GM used the sensing wire and the exciter wire.
Depending on your wants and needs, either should work well.
The one you have picked should be fine.
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