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Author Topic:   Alternator?
H8CHEVY
Gearhead

Posts: 276
From: Southern Cali
Registered: Jun 2000

posted 03-28-2002 02:37 PM     Click Here to See the Profile for H8CHEVY   Click Here to Email H8CHEVY     Edit/Delete Message   Reply w/Quote
Can anyone tell me how many amps the stock alternator pushes? Also what alternator would you guys recommend going with to replace the stock one with? the car seems to be a little dim running all the gauges and elec ignition and so forth.. thanks.

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johnmustang
Gearhead

Posts: 4504
From: Vancouver Island , British Columbia , Canada
Registered: Nov 2001

posted 03-28-2002 02:43 PM     Click Here to See the Profile for johnmustang   Click Here to Email johnmustang     Edit/Delete Message   Reply w/Quote
it should be pushing about 70 - 80 amps.

JOHN

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H8CHEVY
Gearhead

Posts: 276
From: Southern Cali
Registered: Jun 2000

posted 03-28-2002 03:08 PM     Click Here to See the Profile for H8CHEVY   Click Here to Email H8CHEVY     Edit/Delete Message   Reply w/Quote
can anyone recommend a good alternator that will give me more amps than the stock one?

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mellowyellow
Gearhead

Posts: 5739
From: So. Fl.
Registered: Aug 2000

posted 03-28-2002 04:32 PM     Click Here to See the Profile for mellowyellow     Edit/Delete Message   Reply w/Quote
Most every metropolitan area has at leat ONE shop that can take your alternator and increase the output. But you might also want to check all your grounds-they get crusty with age.

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richard bohm
Gearhead

Posts: 373
From: tucson,az-luray,va
Registered: May 2001

posted 03-28-2002 07:38 PM     Click Here to See the Profile for richard bohm   Click Here to Email richard bohm     Edit/Delete Message   Reply w/Quote
the stock alternator puts out about 55 amps. you can get the summit catalog and find ones that put out 140 amps.

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Hemikiller
Gearhead

Posts: 395
From: Clinton, CT
Registered: Feb 2002

posted 03-28-2002 07:42 PM     Click Here to See the Profile for Hemikiller   Click Here to Email Hemikiller     Edit/Delete Message   Reply w/Quote
Stock output depended on the options in the car. Could vary from 35 amps to 80. What year is the car? Also, the part # and output is stamped into the top of the front alternator case by the pivot bolt. Should be visible from the top when installed in the car. Clean it off with a wire brush or some sandpaper.

[This message has been edited by Hemikiller (edited 03-28-2002).]

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 03-28-2002 08:01 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Your stock one is probably under 50 amps.

I purchased a Tuff Stuff alternator in chrome from Jegs for about $140. It looked like a quality piece but failed in one month. I started thinking that it might have been the voltage regulator that caused it to burn out so I rebuilt it rather than waste money on a new one and I put in a new regulator.

When I opened it up the pieces internally looked like top quality stuff. I couldn't tell why it wasn't working except the brushes looked a bit worn. Anyway I rebuilt it and it has been working great.

Long story.. but here is the link where I got the kit from. They have conversion kits for you to change your stock one up to 100amps.

http://www.alternatorparts.com/

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65coupei6
Gearhead

Posts: 415
From: S.F., CA
Registered: May 2000

posted 03-28-2002 08:52 PM     Click Here to See the Profile for 65coupei6   Click Here to Email 65coupei6     Edit/Delete Message   Reply w/Quote
Stock alternators could have been either 35 or 55 amps. You could go for a Power Master Motorsports Alt.

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Fastback68
Gearhead

Posts: 1746
From: Sucat, Paranaque, Philippines
Registered: Jul 99

posted 03-28-2002 11:44 PM     Click Here to See the Profile for Fastback68   Click Here to Email Fastback68     Edit/Delete Message   Reply w/Quote
Used alternators from scrapped cars are easy to come by, cheap, and if the car is not too old they should have 70 or 80 amps output or more. My Nippon Denso one works great and cost me, let me think, $20.

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dubstar
Gearhead

Posts: 423
From: Long Beach, Ca 1966 A-Code Coupe
Registered: Feb 2002

posted 03-29-2002 11:55 AM     Click Here to See the Profile for dubstar   Click Here to Email dubstar     Edit/Delete Message   Reply w/Quote
my headlights run dim and then when i step on the gas they brighten up.. when its idling, they flicker a little bit.. is this the alt's fault?

ps: i have a new voltage regulator.

sorry, i thought i'd piggy back your question.

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[This message has been edited by dubstar (edited 03-29-2002).]

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 03-29-2002 06:49 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Very likely that it is. Your amperage increases when you rev it up. Keep in mind that the older alternators put out about half there output when you are just cruising. Even my new 100 amp unit puts out only 50amps at 2000rpm. It doesn't have all 100amps until 4000rpm. This is one advantage of the late model 3G alternators. Even with the same total capacity they put out more amperage at low rpms.

quote:
Originally posted by dubstar:
my headlights run dim and then when i step on the gas they brighten up.. when its idling, they flicker a little bit.. is this the alt's fault?

ps: i have a new voltage regulator.

sorry, i thought i'd piggy back your question.


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Fastback68
Gearhead

Posts: 1746
From: Sucat, Paranaque, Philippines
Registered: Jul 99

posted 03-29-2002 09:09 PM     Click Here to See the Profile for Fastback68   Click Here to Email Fastback68     Edit/Delete Message   Reply w/Quote
On that subject JAAZZY, I've been offered an old Ford alternator (and I have a Delco one like this too) with two pulleys instead of the normal one. I've been told these overcome this problem by ensuring high ampage while the engine is idling. True? What I can't figure out is what I'm supposed to connect the second pulley to

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Gary
Gearhead

Posts: 725
From: Sarasota, Fla. USA
Registered: Jun 99

posted 03-29-2002 09:42 PM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I have a 100amp alt. I don't like it because below 2000rpm it doesn't charge. So, if your tuning or just sitting at idle your basicly running off the battery. I find I have to charge my battery once every two weeks to keep it up to full charge. This is with regular driving around town, (highway is fine) Im changing mine back down to a 55-65amp. Iv'e been to two shops that specialize in alt. They claim that 100amp altenators don't charge at low rpms and the cure would be using a smaller alt. pulley or changing the alt. to lower output.
If ya ask me what the sense of having a high amp alt.? I got it because I run a elec. fan, elec. fuelpump and was intending previously on re-installing the AC. Figured the 100amper would be the ticket..NOT!

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 03-29-2002 09:58 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
I'm sorry but I don't know anything about these. It doesn't make sense to me either. I don't think I've ever seen one.

quote:
Originally posted by Fastback68:
On that subject JAAZZY, I've been offered an old Ford alternator (and I have a Delco one like this too) with two pulleys instead of the normal one. I've been told these overcome this problem by ensuring high ampage while the engine is idling. True? What I can't figure out is what I'm supposed to connect the second pulley to

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 03-29-2002 10:04 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Gary,

I thought the same situation existed with the 65 amp alternators. In that they only put out around 40 amps at 2000rpm.

If I leave my car running at idle for extended periods with both electic fans running I just barely make enough juice to keep the battery charged, maybe loosing a little but when crusing around even at 2000rpm which is normal for me even around town it stays charged fine. To overcome some of the problem at idle I went with the Yellow Top Optima so it doesn't mind loosing some of its charge and then recharging. It also has a long reserve and so far it seems to be working fine.

quote:
Originally posted by Gary:
I have a 100amp alt. I don't like it because below 2000rpm it doesn't charge. So, if your tuning or just sitting at idle your basicly running off the battery. I find I have to charge my battery once every two weeks to keep it up to full charge. This is with regular driving around town, (highway is fine) Im changing mine back down to a 55-65amp. Iv'e been to two shops that specialize in alt. They claim that 100amp altenators don't charge at low rpms and the cure would be using a smaller alt. pulley or changing the alt. to lower output.
If ya ask me what the sense of having a high amp alt.? I got it because I run a elec. fan, elec. fuelpump and was intending previously on re-installing the AC. Figured the 100amper would be the ticket..NOT!

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65coupei6
Gearhead

Posts: 415
From: S.F., CA
Registered: May 2000

posted 03-29-2002 11:50 PM     Click Here to See the Profile for 65coupei6   Click Here to Email 65coupei6     Edit/Delete Message   Reply w/Quote
From what I have found alternators are rated differently. So as people have said before a 100amp alt. will not put it out until it reaches a certain rpm range. The best alternators I have found are from Power Master but they are expensive. Actually they come out to be about the same cost as a 3G.

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Gary
Gearhead

Posts: 725
From: Sarasota, Fla. USA
Registered: Jun 99

posted 03-30-2002 07:04 AM     Click Here to See the Profile for Gary   Click Here to Email Gary     Edit/Delete Message   Reply w/Quote
I was not aware that even the 65ampers charge in the upper rpm range too, the shop where im taking mine claims he can re-work my 100amp by changing the stator so it will remain @ zero at idle, niether charge or dis-charge. From there, charging back as demand requires. Im taking the alt. down to them next week, will let you know how it works out.

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 03-30-2002 08:27 PM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
Gary,

I believe this is a symptom of all alternators it is just less pronounced on the late model 3G style. Check out this link from PowerMaster. There are three different early style alternators. In each case the higher total output alternators also have a higher idle output. When I think about it, it doesn't make sense any other way. I think in every street application the problem is always at low rpms.

I forgot to add the link.
http://www.powermastermotorsports.com/Chrome/Ford_Early_Style_Chrome/ford_early_style_chrome.html

quote:
Originally posted by Gary:
I was not aware that even the 65ampers charge in the upper rpm range too, the shop where im taking mine claims he can re-work my 100amp by changing the stator so it will remain @ zero at idle, niether charge or dis-charge. From there, charging back as demand requires. Im taking the alt. down to them next week, will let you know how it works out.

[This message has been edited by JAAZZY (edited 03-30-2002).]

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H8CHEVY
Gearhead

Posts: 276
From: Southern Cali
Registered: Jun 2000

posted 03-30-2002 08:41 PM     Click Here to See the Profile for H8CHEVY   Click Here to Email H8CHEVY     Edit/Delete Message   Reply w/Quote
So gentlemen what are your comments on these "Power Pulleys" designed bye Power Master ??? will they help that low charge at idle? or is it a waste of time...? sounds like its almost a waste of money to buy one of those 100amp alt. if they dont charge well at idle..?

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JAAZZY
Gearhead

Posts: 745
From: Bay Area, CA
Registered: Apr 2001

posted 04-01-2002 11:19 AM     Click Here to See the Profile for JAAZZY     Edit/Delete Message   Reply w/Quote
I don't know anything about the power pulley but my guessis that it is just smaller in diameter so that it spins faster for a given rpm. It would thus put out more power at idle.

My 100amp alternator is fine. Remember I run two electric fans and fuel injection, with an electric fuel pump and my car is staying charged. If I spent all my time at idle is the only way I might start loosing charge but I actually think it would stay steady neither gaining or loosing. For most applications it should be fine. Power Mastr even has a 140amp early style alternator. That puts out about 20amps more at idle. The only cars that need more power are the ones with the 1000watt stereo systems.

quote:
Originally posted by H8CHEVY:
So gentlemen what are your comments on these "Power Pulleys" designed bye Power Master ??? will they help that low charge at idle? or is it a waste of time...? sounds like its almost a waste of money to buy one of those 100amp alt. if they dont charge well at idle..?

[This message has been edited by JAAZZY (edited 04-01-2002).]

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