3G advice

ArdWrknTrk wrote

The alternator I've used fits well.
It also has the smaller 8x1.25 adjuster hole, so you can just run a 3/8-16 tap through. (No need to helicoil the larger 10mm hole down to work)
You'll need to take a little of the offset out of your curved adjuster bracket.
I think the boss on the 3G is a 1/4" thicker.

Yep take the offset out or mount the alternator and use the bracket as a guide and mark the alternator and cut the ear down on the alternator.  That is the route I am thinking of going to allow me to swap a 1G back in an emergency situation.

Machspeed wrote

WOW, I've been doing the same thing and was just fixing to post on this when I saw your post. Rather than make another post, hope you don't mind if I add to it!

After a post I made here on a truck fire and the noted frequent fires and associated causes, I am attempting to eliminate all possible causes for a fire. One of those is the 2G alternator for which I’ve read are high on that list for potential fire causes. I still have my original OEM 2G alternator, thus my desire to make the change to the 3G. Know that I do not plan to add much more to my truck in regards to its current electrical load. At best, I may add a small amp to the newly installed stereo and upgrade the headlights. I’ve already don the harness change and added a new light switch.

I’ve read through our resources on the 3G conversion for which Gary and company did an exceptional job. Still, I’m left with questions. Want to start out with just a few and add to it.

My Truck: 351HO, Edlebrock Carb with electric choke, V-Belt system, no power windows or power locks.
 
1. Am I correct that my current V belt alternator has an 8.25” mount spacing?

2. If so, in the list of donor cars for which one can pull a 3G alternator and associated parts, do all those
    have an 8.25” mount spacing?

3. As my truck won’t need much more than the current 2G alternator is supplying, would it matter if I
   went with a 90 Amp alternator or a 130 Amp?

You can run the 90A version but it has a narrower ear spacing.  It will work but in many cases the OE belt wont fit as the narrower ear spacing from what I have read wont allow the alternator to move over enough for the OE sized belt to fit.  Not that huge of a deal as you can always up the belt size one or two sizes so it will fit, This also will reduce how much swing you have as well for tensioning the belt.  Big reason why I am thinking I will just go with the 130A anyways even though for a single V-belt setup it would slip easily.

I have been trying to get Goodyear to help me with picking out a V belt that would fit the pulley grooves properly but has a higher grip, it would help with slippage but with the virus going on it seems like they arent too thrilled to help.  If you can run a dual belt setup it would be recommended with a 130A, I cant run a dual belt setup without losing my dealer A/C.

Gary Lewis wrote

John - I'm not an expert here, but I just measured the 1G I have and I found that it is 7" c/c on the bolts.  So I'm confused as I would expect your 2G to fit in the same spot.  But our page says "* Trucks that currently have V-Belts use the 8.125” mounts, and trucks that have serpentine belts use the 7” mount spacing. (* Need to verify this info)."  So I don't have good answers.

Given that, I'm tagging Jim, who seems to have a better handle on this than I do.

Thats the measurement I got from a 1G alternator I took off the 82 truck at work that we threw the 5.0 Coyote in.  I been meaning to take my actual 1G off on my truck and measure it and verify if its 7" also.  If it is then I would be very happy as it means I can run the 95A 3G and retain the OE belt and not have to worry about belt slip.  Just would have to double check my soft start regulator as I cant remember if it was 130A only or if it is backwards compatible with the 95A version as well.

I cant take the other 1G alternator as the final say on size cause it has a 1 sheave pulley as the air pump was deleted on that truck when the engine was built and as far as I know that alternator could be incorrect.  My truck how ever I know is original to the truck and it is the right one.

Rusty,
It doesn't matter what the 3G output is, the regulators (and brush holders) are the same.

As for Tyler's 1G, I'm pretty sure there are 1G models from 35 all the way up to 95 or 100A, but he seems to have a problem keeping the battery charged, so his 1G (and any other 1G) just isn't putting out enough at low revs to feed the fuel pump, blower and lights and maintain a stable voltage for the fuel injection computer.

At least this is my understanding of the opening post.

Rusty_S85 wrote

Yep take the offset out or mount the alternator and use the bracket as a guide and mark the alternator and cut the ear down on the alternator.  That is the route I am thinking of going to allow me to swap a 1G back in an emergency situation.

I don't want to lose 1/4" of thread engagement on the adjuster bolt, so I'm not cutting down my alternators 'ear'.

I'm not sure how easy it would be to go back to a 1G, unless your 3G upgrade includes the PA Performance 'dummy' external regulator.
Then -maybe- you could swap the regulator and put the old 1G back in.

Honestly, I'd just walk into any auto parts store on the planet, buy an alternator for a Taurus and have them swap the pulley and shim.

<quote author="ArdWrknTrk">

Rusty_S85 wrote

Honestly, I'd just walk into any auto parts store on the planet, buy an alternator for a Taurus and have them swap the pulley and shim.

I went to three parts stores yesterday just to look at a Taurus alternator and no one had it in stock. I don't think that alternator is an easy score in so much as getting it same day. Also, spent much time on the web looking through our local salvage yards for a donor car and came up empty. Basically, would like to acquire the harness and alternator for fit up purposes. I'm off today and am going to scour Tulsa salvage yards. Sadly, more and more yards won't let you in, they want to pull the parts. Moreover, their inventory for older vehicles for me to pull from is very limited.  

I spent a great deal of time yesterday pursuing the web on the study of this mod, as my knowledge base on electrical is limited and I don't do anything without study and a plan. There is much conflicting information, one of which is the C-C distance on the alternator of my truck. Many say it is 8.250". As such, I went out last night and removed the sucker to measure, even though I had previously gotten a rough measure of it while it was on the truck. Regardless, it is 7.00" and it is the OEM unit that was on the truck when I bought it new. Additionally, it appears I can get an alternator off 94-97 thunderbird/Cougar with the 3.8 and 94-95 Mustang with V8, but I think the wiring goes in through the top, though I think I can clock that alternator to bring it to the bottom???

Looking at my current pulley configuration, it appears that I will only be able to run a single belt to the new alternator. I read all this stuff about belt slippage when upgrading the alternator, but if I'm not changing components to increase the draw, do I really have to worry about this? What difference does it make if I go from my 60 amp alternator to a 130 amp if I'm not adding heavy lighting, stereo amps, snow plows and stuff?  



 

Yes, your alternator has 7" between the mounting holes.  But can the arm be swung far enough to take the larger alternator?  In the case of Dad's truck the answer was yes.

On the belt/pulley question, I think you'll be fine with a single belt.  In normal circumstances you won't be drawing the battery down enough to cause the alternator to throw 130 amps, so the single belt will be adequate.  And if you do get to a situation where the belt is being asked to transfer more power than it can w/o slipping, just let the engine idle for a bit.  At idle the 3G puts out about 100 amps and I think the belt can live at that load.  I might be noisy, but it will live.

As for the alternator, why not get the one from DB Electric that Jim is using?  It is an AFD0028 and is said to be for a 3.8L Taurus Sable from 90-93 or Continental from 91-94.  It has the LRC regulator that will be a help with the single belt.  But it is clocked such that the plug is at 7:00 o'clock rather than 11:00 like some, although you can change that.

Gary, thank you! I'm on information overload reading up on this stuff. And right now, the biggest question is, will I have enough swing with what I order? I have a 7" C-C but do I need the 7" or 8" C-C to make the needed tension. Indeed, I have been looking at the alternator that Jim and you posted but want confirmation that I will be able to tension it on my 351? Think you guys have 460's with a different belt configuration.    

I just read this in a FB post.  "I found some info on one of the forums and bought an alternator, mega fuse, wire, and the plugs necessary. I then looked more into it and found my alternator mounts were small and the alternator I bought were big so I bought another alternator. Got the alt side wiring complete and set the small pattern alt in place only to find the case is larger and does not allow enough pivot for the factory belt to reach. So I pull that alt, wire up the originally purchased alt and set in place with success. Only issue with this one is the bolt hole for the swing arm mount is smaller than factory but no biggie, smaller bolt fixes that."

Don't want to go through what he did. BTW, he also has a 460.

Dont get me wrong John, a lot of those guys on face book couldent find their a......head with both hands and a map.

old55pete wrote

Dont get me wrong John, a lot of those guys on face book couldn't find their a......head with both hands and a map.

LOL! Oh hey, did you get the hinge I sent you?

No sir, the hinge has not arrived yet.

Machspeed wrote

  "I found some info on one of the forums and bought an alternator, mega fuse, wire, and the plugs necessary. I then looked more into it and found my alternator mounts were small and the alternator I bought were big so I bought another alternator. Got the alt side wiring complete and set the small pattern alt in place only to find the case is larger and does not allow enough pivot for the factory belt to reach. So I pull that alt, wire up the originally purchased alt and set in place with success. Only issue with this one is the bolt hole for the swing arm mount is smaller than factory but no biggie, smaller bolt fixes that."

This is exactly the case John.

If people choose to ignore the best advice offered then they can't be helped.
I suggest instead of using a smaller 8x1.25 metric bolt in the adjuster you simply run a 3/16-18 tap through that tapped hole.

Go over to FSB and have a look at the EPIC 3G thread there.
Clarko and Ryan both participated, I believe?
Anyway, I don't want or need to reiterate myself for 19 pages like he does.

ArdWrknTrk wrote

<
If people choose to ignore the best advice offered then they can't be helped.
I suggest instead of using a smaller 8x1.25 metric bolt in the adjuster you simply run a 3/16-18 tap through that tapped hole.

Jim, being 8mm is closer to 5/16, wouldent you want to tap the hole to 5/16-18 ?

I know it is Steve, but the slot in the adjuster and the bolt from my 2G are 3/8.
I don't want a sloppy fit or a scrawny bolt. And I had the 3/8-16 bolt in my hand from taking the 2G out.

Heck, I didn't even drill the 8mm hole out.
The (aluminum?) alloy is crumbly enough you can force a taper tap right in.
No curls. It taps like cast iron.

ArdWrknTrk wrote

Rusty,
It doesn't matter what the 3G output is, the regulators (and brush holders) are the same.

As for Tyler's 1G, I'm pretty sure there are 1G models from 35 all the way up to 95 or 100A, but he seems to have a problem keeping the battery charged, so his 1G (and any other 1G) just isn't putting out enough at low revs to feed the fuel pump, blower and lights and maintain a stable voltage for the fuel injection computer.

At least this is my understanding of the opening post.

Yep I checked last night before bed and saw the regulator is the same regardless 95A or 130A.

His 1G might be the small one like my truck, my truck is a 60A 1G but the 1G on my '78 Mercury is a 75A unit and you cant find them hardly anymore.  I also didnt see that he upgraded to the sniper, that is also a big reason why I am doing my 3G upgrade if it wasnt for that I would just let my 1G ride till the alternator finally goes out and then do the upgrade.

ArdWrknTrk wrote

Rusty_S85 wrote

Yep take the offset out or mount the alternator and use the bracket as a guide and mark the alternator and cut the ear down on the alternator.  That is the route I am thinking of going to allow me to swap a 1G back in an emergency situation.

I don't want to lose 1/4" of thread engagement on the adjuster bolt, so I'm not cutting down my alternators 'ear'.

I'm not sure how easy it would be to go back to a 1G, unless your 3G upgrade includes the PA Performance 'dummy' external regulator.
Then -maybe- you could swap the regulator and put the old 1G back in.

Honestly, I'd just walk into any auto parts store on the planet, buy an alternator for a Taurus and have them swap the pulley and shim.

I did a comparison, the thickness of the ear after being cut down looks to be not that much thinner than the OE 1G alternator ear.  I honestly dont believe losing a little of the ear thickness would be that drastic.

For mine I was going to leave the 1G regulator bolted on and I wont be chopping wires,  Im currently looking for a proper connector for the alternator connector to simply plug into.  Otherwise I am going to use a spade connector to make my excite connection.

<quote author="Machspeed">

ArdWrknTrk wrote

Rusty_S85 wrote

Honestly, I'd just walk into any auto parts store on the planet, buy an alternator for a Taurus and have them swap the pulley and shim.

I went to three parts stores yesterday just to look at a Taurus alternator and no one had it in stock. I don't think that alternator is an easy score in so much as getting it same day. Also, spent much time on the web looking through our local salvage yards for a donor car and came up empty. Basically, would like to acquire the harness and alternator for fit up purposes. I'm off today and am going to scour Tulsa salvage yards. Sadly, more and more yards won't let you in, they want to pull the parts. Moreover, their inventory for older vehicles for me to pull from is very limited.  

I spent a great deal of time yesterday pursuing the web on the study of this mod, as my knowledge base on electrical is limited and I don't do anything without study and a plan. There is much conflicting information, one of which is the C-C distance on the alternator of my truck. Many say it is 8.250". As such, I went out last night and removed the sucker to measure, even though I had previously gotten a rough measure of it while it was on the truck. Regardless, it is 7.00" and it is the OEM unit that was on the truck when I bought it new. Additionally, it appears I can get an alternator off 94-97 thunderbird/Cougar with the 3.8 and 94-95 Mustang with V8, but I think the wiring goes in through the top, though I think I can clock that alternator to bring it to the bottom???

Looking at my current pulley configuration, it appears that I will only be able to run a single belt to the new alternator. I read all this stuff about belt slippage when upgrading the alternator, but if I'm not changing components to increase the draw, do I really have to worry about this? What difference does it make if I go from my 60 amp alternator to a 130 amp if I'm not adding heavy lighting, stereo amps, snow plows and stuff?

The output is load based, more systems you are running the more amps will be put out.  The alternator will output slightly more than required to not only run all accessories but as well as to provide a slight charge to your battery.

So if all systems you have are pulling say 40A the alternator would in theory be putting out no more than 60A to 65A to power the systems and charge the battery at the same time.

Another thing to keep in mind, as battery voltage goes up, amperage goes down.  So an electrical component such as a headlight for example pulling 4.29A at 12.8 nominal would be at a 3G voltage set point of 14.3V be pulling just 3.85A.  While yes it is minimal reduction the reductions do add up.  It is something to keep in mind and thats why I really want to run the 95A 3G unit over the 130A unit as I dont believe my system even with another 400w worth of auxiliary lighting would put me at max output.

400w worth of auxiliary halogen lights is 27.97A draw, two headlights on high is 8.39A draw, 200w driving lights 13.98A draw, figure another 15A for AC draw, 15A for Sniper, and another 15A for the CB radio and amp would be 95.34A which I am being generous with draw for the AC/Sniper/CB not to mention there is no set plan for me to add four more auxiliary lights and if I wanted to I could in theory dump the 100w bulbs for 50w bulbs and half the power requirement and reduce draw to 13.98A.

Ideally 130A would be ideal as it will last longer but in most cases I do not believe 130A is needed.  I settled on the 130A as I am under the impression that I need the larger wide ear spacing and I havent measured my 1G alternator but I measured one off another truck and you have yours as well as others stating 7" which has me seriously rethinking the 130A 3G since it opens me up to the small case 95A version.

You need to understand the difference between resistive and inductive load....

Yes, of course output is load based. That's the point of having a regulator, not just a Load Response Control regulator.

Tyler should get a 3G because it will put out as much at idle as his 1G can at redline.
I don't care what the regulator is calling for, the 1G is gutless until it is spinning something like 8,000 rpm (alternator RPM)
The reason for the 130A 3G is not "130A!", it's the 100A available  at idle.

The 1G was introduced in the 1964 1/2 Mustang.
A lot happened in the 26 years between that and the introduction of the 3G.

The alternator puts out set point voltage.
Amperage is simply how much current at that voltage is required to keep the volts at the set point of the regulator (in my case 14.35V)

Gary has a degree in this stuff.
I'm not an EE, but I do have a grasp how a simple alternator works.

You don't need the 8.25" ear spacing if you're using the smaller body (135mm) 95A 3G.
But you're not going to get 100A at idle from the smaller output 3G either, and the smaller fans and rectifier board heatsink are going to have it running much hotter than a 130 at the same load.

Wow, a lot of discussion has happened since I went to work!  Fuse harness from Painless was on my doorstep and the alternator will be here tomorrow so I can get that started.

And, if you saw my other thread...all this lack of power actually came from me having a different issue which is probably a ground or lack thereof.

Once the truck comes back from the exhaust shop tomorrow morning,  I'll do some more troubleshooting with my taillights.

I actually think the 1G would have hacked it just fine with the Sniper and fuel pump.

Thanks for all the info.  I'm loving this group!

You are going to like the 3G.  The lights will stay bright at idle.  Wiring will be cleaner w/o the regulator on the fender.  Definitely a good upgrade in spite of the other problem.

As for the group, we have a lot of really good, and knowledgeable people.