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Topic: Can a 3g be damaging overkill? (Read 18294 times) previous topic - next topic

Can a 3g be damaging overkill?

The alternator in my 88 5.0 TC just died and some of the wiring (which was previously extended with some poor solder joints) went with it.  So, since I'm rewiring AND buying an alternator I was thinking 3g...  But, since I have only LOWERED the electrical stress on the system (no ABS, PRC and no aftermarket stereo - for now) could the 3g just simply be too much for the car?  Or doesn't it matter?  Won't cost much more so I figured, might as well.
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Can a 3g be damaging overkill?

Reply #1
Go 3G.I did it some time ago.I didn't have any extra electrical items on the car at that time,and was still glad I did it.I didn't have the dim lights when every accessory was turned on (like the heater,defroster,lights,radio,fog lights).Easy to do,and you'll already have it done when you do decide to do any upgrades.It's not overkill.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Can a 3g be damaging overkill?

Reply #2
Yeah I dont think its overkill either as I put in a 200 amp from PA performance just because. I dont even have a kickin radio either.
1985 Thunderbird TC
2.3l .03 over,Ported and polished Head and E6 Manifold, LA3, T3/T4 Hybrid Turbo, Stinger FMIC, Forge BOV, Full 3" Exhaust, Essy Timing Gears & UDP's, BBK 255lph Fuel Pump, Kirban AFPR, Kirban Short Shifter, K&N Cone, Forced4 VC Vent Kit, PA Performance 3g Alternator, Energy Suspension Bushings throughout, CHE LCA's, SFC's [/LEFT]

Can a 3g be damaging overkill?

Reply #3
I'd not be worried about overkill - so long as the charging wire can handle the current if the battery were to get discharged. I'm using a 95A version and it's perfect for my needs.
11.96 @ 118 MPH old 306 KB; 428W coming soon.

Can a 3g be damaging overkill?

Reply #4
If it's good enough for a 3.0 Taurus,surely it's not overkill for a 5.0.
'88 Sport--T-5,MGW shifter,Trick Flow R intake,Ed Curtis cam,Trick Flow heads,Scorpion rockers,75mm Accufab t-body,3G,mini starter,Taurus fan,BBK long tube headers,O/R H-Pipe, Flowamaster Super 44's, deep and deeper Cobra R wheels, Mass Air and 24's,8.8 with 3.73's,140 mph speedo,Mach 1 chin spoiler,SN-95 springs,CHE control arms,aluminum drive shaft and a lot more..

Can a 3g be damaging overkill?

Reply #5
Yes, it CAN be overkill, and possibly burn your car down. However, 99% of the time, it will turn out just fine, and everything will work even better than before the swap.

But, like everything in life, there is that .01% chance something catastrophic will occur, and if it does....watch out.
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
[/SIZE]

Can a 3g be damaging overkill?

Reply #6
Yes in my car I added heavier gauge wire. As reccomended by PA Performance
1985 Thunderbird TC
2.3l .03 over,Ported and polished Head and E6 Manifold, LA3, T3/T4 Hybrid Turbo, Stinger FMIC, Forge BOV, Full 3" Exhaust, Essy Timing Gears & UDP's, BBK 255lph Fuel Pump, Kirban AFPR, Kirban Short Shifter, K&N Cone, Forced4 VC Vent Kit, PA Performance 3g Alternator, Energy Suspension Bushings throughout, CHE LCA's, SFC's [/LEFT]

Can a 3g be damaging overkill?

Reply #7
Quote from: DMC24guy;178148
Yes, it CAN be overkill, and possibly burn your car down. However, 99% of the time, it will turn out just fine, and everything will work even better than before the swap.

But, like everything in life, there is that .01% chance something catastrophic will occur, and if it does....watch out.


Just because you botched the install, it doesn't mean that it's overkill.  The fact that you installed a 3G alt was not the reason for your car to catch fire, it was the install.

If you don't need a higher amperage unit, one like a 95A would be fine and you'd benefit from a more efficient, up-to-date unit.  However, the output amperage has no effect on the output voltage, just how well it can feed the required amp load.  A 130A would be fine if that's what you can find.  The key is to make sure your output  wiring can handle the potential output of whatever alt you choose, and to install the unit correctly.
Long live the 4-eyes!  - '83 Tbird Turbo - '85 Marquis LTS - '86 LTD Wagon-  '81 Granada GL 2dr

Can a 3g be damaging overkill?

Reply #8
So, I can rewire the output wiring but I'm confused as to why all the other wiring in the car wouldn't have to be upgraded...

Anyway, another question, 'cause the local auto parts stores are retarded and I just spent hours with 3 stores that can't use there alternator testing machines right (btw, still trying to figure if my alt IS indeed bad):

So, like I said, a solder joint inches from the alternator output stud failed.  Sometime before/after that the rubber boot covering the stud also completely melted (I'm guessing this allowed arcing and heating of the solder joint).  So, I re-soldered the joint just for testing, recharged the battery (it died while I attempted to get out of the intersection) and checked voltage across the battery.  Got something like 12.2v.  Then fired the car and it dropped to 10.9v.  So, at first I figured this meant the alternator wasn't charging.  But then I thought, maybe the alternator is fine, my wiring is still bad somewhere and the voltage drop is just from the computer and ignition, etc... running..  What do you guys think?  Is there a better way to test my alternator?  Can I put my DVM on the output stud and test right there to see if it gives voltage before the wiring?
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Can a 3g be damaging overkill?

Reply #9
The only wire in the car that has to be upgraded is the one between the output stud on the alternator and the solenoid. It is the only wire that is carrying the alternator's output.

If the wire is sized properly and fused properly there is no danger of "overkill". The things have a voltage regulator in 'em for a reason. The alternator will only put out what is required to keep the battery charged. If your total draw on the battery is 30 amps (fuel pump, EEC, blower motor, for example) the alternator will only put 30 amps out.

The real advantage of a 3G swap is that not only does it have a higher peak capacity, it is also running more efficiently and will last longer at "normal" charging rates. A stock 65 amp alternator putting 40 amps out is running at 67% capacity, while a 95 amp 3G is only running at 42%. A 130-amp is only running at 30%, so it's hardly breaking a sweat.

Yes, you can test the voltage right at the output stud. Normally, though, when a battery goes bad the charging voltage actually goes up - the alternator is putting out more power, trying to forcefeed a battery that won't take it.
2015 Mustang GT Premium - 5.0, 6-speed, Guard Green - too much awesome for one car

1988 5.0 Thunderbird :birdsmily: SOLD SEPT 11 2010: TC front clip/hood ♣ Body & paint completed Oct 2007 ♣ 3.55 TC rear end and front brakes ♣ TC interior ♣ CHE rear control arms (adjustable lowers) ♣ 2001 Bullitt springs ♣ Energy suspension poly busings ♣ Kenne Brown subframe connectors ♣ CWE engine mounts ♣ Thundercat sequential turn signals ♣ Explorer overhead console (temp/compass display) ♣ 2.25" off-road dual exhaust ♣ T-5 transmission swap completed Jan 2009 ♣

Can a 3g be damaging overkill?

Reply #10
Ahh, I get it...  the voltage regulator!  :hick:

So, can I do any tests and tell anything with what I have...  or do I have to journey to distant parts stores in search of someone who can actually test my alternator?

And last question...  With so many posts about a 3g upgrade I'm confused.  The "reply 49" on the official sticky shows a "final" diagram that seems to have more plugs than my setup and the tech article on nato has me adding 3 wires from the output stud and modifying the bundle of fuse links, etc...  I know it's been discussed a lot, and I've read it all, but still can't seem to find a final 88TC diagram.  What directions do I follow?


EDIT:  There are two 130 amp 3g's on paperformance.com.  I'm in a bind and need to either order one of those or a stock replacement tonight...  can some one tell me which one is the one I need?  I can't tell the difference between them...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Can a 3g be damaging overkill?

Reply #11
One more thing... there are two 130 amp 3g's on paperformance.com.  I need to either order one of those or a stock replacement tonight...  can some one tell me which one is the one I need?  I can't tell the difference between them...
1988 Thunderbird Turbo Coupe
'89 5.0 w/ ported intakes, Mallory Adjustable FPR, BBK shorties and H with 2.5" Flows, 130 amp 3G, 89 Mustang comp/wiring, Aluminum radiator w/ elec fan, T5 trans, King Cobra clutch, 3.55 gears, 13" Cobra brakes (front), Wilwood prop valve, Mustang A-arms, Front Coil-overs, MM CC plates, Silver 17x9 R's, 03 Cobra IRS, Aluminum DS, 2002 Mustang dash/console etc..., custom leather seats

Can a 3g be damaging overkill?

Reply #12
Quote from: Cougar5.0;178137
I'd not be worried about overkill - so long as the charging wire can handle the current if the battery were to get discharged. I'm using a 95A version and it's perfect for my needs.


That's an interesting point. I don't know what the maximum current a discharged battery can draw is. If the stock wiring is left in place it would blow the fuse link between the alternator output and the battery if it drew too much current.

Quote from: booksix;178160
So, I can rewire the output wiring but I'm confused as to why all the other wiring in the car wouldn't have to be upgraded...


Look at it this way: If the power plant installs extra turbines and doubles its' power output capability you don't have to upgrade your house wiring.

Quote
So, like I said, a solder joint inches from the alternator output stud failed.  Sometime before/after that the rubber boot covering the stud also completely melted (I'm guessing this allowed arcing and heating of the solder joint).


If a good solder joint got hot enough to melt the solder you are drawing way too much current through that alternator output wire.
This makes me wonder if your wiring is stock and if you have a fuse link between the alternator.
A bad solder joint may overheat because it's a bad solder joint.

Quote
So, I re-soldered the joint just for testing, recharged the battery (it died while I attempted to get out of the intersection) and checked voltage across the battery.  Got something like 12.2v.  Then fired the car and it dropped to 10.9v.  So, at first I figured this meant the alternator wasn't charging.  But then I thought, maybe the alternator is fine, my wiring is still bad somewhere and the voltage drop is just from the computer and ignition, etc... running..  What do you guys think?


I don't think the computer,ignition and fuel pump should drag the voltage down that much. Disconnect the output wire from the alternator. Recharge the battery and start the car with the alternator wire disconnected. Check the battery voltage after it has been running a few minutes to give the battery time to recover from running the starter motor.If the voltage is still  down to 10.9 you may have a weak battery and a bad alternator.

If the voltage is now good you have bad alternator that is putting a load on the battery. This would explain the wire overheating.

Quote
Can I put my DVM on the output stud and test right there to see if it gives voltage before the wiring?


Yes

 

Can a 3g be damaging overkill?

Reply #13
Quote from: Chuck W;178153
Just because you botched the install, it doesn't mean that it's overkill.  The fact that you installed a 3G alt was not the reason for your car to catch fire, it was the install.



I did NOT botch the installation. I followed the official instructions over at NATO, used all the components recommended in that Installation guide, yet it caught fire. You are WRONG.
<---One must always remember to Remain cool, calm and collected when dealing with your fellow man, especially on the Internet....
-DMC24guy
[/SIZE]

Can a 3g be damaging overkill?

Reply #14
uh-oh - the guy in the sig is talking to ya :D
11.96 @ 118 MPH old 306 KB; 428W coming soon.