I’m wanting to upgrade my alternator to either a 150 or 200 amp alternator. I want to do a 3g with solid state voltage regulator. I dont want to break the bank, but i dont want cheap either, the is an og 70,000 mile beauty that I’m trying to keep as close to original as possible. Thanks for any suggestions
91 LX 5.0 Convertible needs an alternator upgrade
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How about a 150 amp 2G?
You would still need to upgrade the feed wire and install a fuse.
You would still need to upgrade the feed wire and install a fuse.
Thanks for the reply, but that’s what i dont know. I’m not sure, everything i can find to read about recommends a 150 3G with solid state VR. I’m just curious as to what folks are finding out after they’ve ran different ones for a while. I’m pretty ignorant about all the electrical, although I’m learning a lot thanks to YouTube. I’d really like to hear what an old school mechanic or somebody that’s owned these for years and worked on them theirselves, has to say and can explain why that one does best. I’m truly envious of all you guys that work on your own stuff all the time.
Yeah, I'm a Noob.
You should check with somebody that's been around these cars for a while.
You should check with somebody that's been around these cars for a while.
I can't give you a direct comparison between the 2g and 3g, but I swapped from a 1g to a 3g into my Cobra II and it's been a wonderful upgrade. The old 1g just couldn't keep up with the addition of fuel injection, the required electric fuel pump, electric fan, and an AF gauge. If your car is basically stock - and you're looking to keep it that way - a 3g would be plenty. But you'll need to buy the necessary pieces to install it correctly. There are quite a few threads I've found just doing a quick Google search; here's a few on Motor Trend's site alone.
And here's my thread when I swapped one into my II:
And here's my thread when I swapped one into my II:
Sir, I apologize if i offended you, but I have no idea of your background. I’m just looking for anyone to explain the differences in these things and the pros and cons. I’m literally looking for someone to educate me on this, that’s all. I dont know why I would use the one you suggested, that was the whole point of my post. Just trying to learn all this where I can start doing all my own maintenance because its almost impossible to find anyone to work on these older cars
Thanks a lot. I’ll check these links out!I can't give you a direct comparison between the 2g and 3g, but I swapped from a 1g to a 3g into my Cobra II and it's been a wonderful upgrade. The old 1g just couldn't keep up with the addition of fuel injection, the required electric fuel pump, electric fan, and an AF gauge. If your car is basically stock - and you're looking to keep it that way - a 3g would be plenty. But you'll need to buy the necessary pieces to install it correctly. There are quite a few threads I've found just doing a quick Google search; here's a few on Motor Trend's site alone.
And here's my thread when I swapped one into my II:
Is this you?
Here's really the only thing I can share in comparison to the 2g. I had one in an engine swap I did in my old 84 vert. They alternator locked up on me while driving down the highway. If you read through my thread, someone (I can't recall who atm....) said that their biggest problem was that they were barely putting out adequate amperage for the car at the time. So once you add a bigger draw - i.e. a stereo with a big amp - the alternator wouldn't keep up.
To understand the charging system takes at least a basic understanding of the concepts of electricity. I'm by no means an expert, and I'll probably screw this up, but I'll give my shot at explaining what I know. Try to equate this to water. You have volts, amps, and ohms. Volts is the amount of water, amps is how much pressure the water is giving, and ohms is resistance - i.e. a straw. All alternators put out roughly the same amount of volts (water), but as time has progressed, more systems need the same required amount of water, thereby needing an increase in pressure to supply them. Where ohms/resistance comes in is when you have a bottleneck, such as how much pressure a certain piece of equipment needs or how small of a wire you're trying to feed that piece of equipment to. This is why you'll want a heavier gage wire for things that take a lot of amperage, so that wire doesn't impede the flow of volts. So, by upgrading from, let's say a 65 amp alternator to, say, a 95 amp alternator, you're ensuring there will be enough pressure (amps) to feed all of your bottlenecks so they all have the adequate amount of volts.
Hopefully this makes sense and helps steer you in a good direction. I'll let whomever wants to correct me and/or re-explain if it doesn't make sense.
Best of luck my friend!
Here's really the only thing I can share in comparison to the 2g. I had one in an engine swap I did in my old 84 vert. They alternator locked up on me while driving down the highway. If you read through my thread, someone (I can't recall who atm....) said that their biggest problem was that they were barely putting out adequate amperage for the car at the time. So once you add a bigger draw - i.e. a stereo with a big amp - the alternator wouldn't keep up.
To understand the charging system takes at least a basic understanding of the concepts of electricity. I'm by no means an expert, and I'll probably screw this up, but I'll give my shot at explaining what I know. Try to equate this to water. You have volts, amps, and ohms. Volts is the amount of water, amps is how much pressure the water is giving, and ohms is resistance - i.e. a straw. All alternators put out roughly the same amount of volts (water), but as time has progressed, more systems need the same required amount of water, thereby needing an increase in pressure to supply them. Where ohms/resistance comes in is when you have a bottleneck, such as how much pressure a certain piece of equipment needs or how small of a wire you're trying to feed that piece of equipment to. This is why you'll want a heavier gage wire for things that take a lot of amperage, so that wire doesn't impede the flow of volts. So, by upgrading from, let's say a 65 amp alternator to, say, a 95 amp alternator, you're ensuring there will be enough pressure (amps) to feed all of your bottlenecks so they all have the adequate amount of volts.
Hopefully this makes sense and helps steer you in a good direction. I'll let whomever wants to correct me and/or re-explain if it doesn't make sense.
Best of luck my friend!
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Thanks a lot bro. You pretty much told me what I was looking for.Is this you?
Here's really the only thing I can share in comparison to the 2g. I had one in an engine swap I did in my old 84 vert. They alternator locked up on me while driving down the highway. If you read through my thread, someone (I can't recall who atm....) said that they're biggest problem was that they were barely putting out adequate amperage for the car at the time. So once you add a bigger draw - i.e. a stereo with a big amp - the alternator wouldn't keep up.
To understand the charging system takes at least a basic understanding of the concepts of electricity. I'm by no means an expert, and I'll probably screw this up, but I'll give my shot at explaining what I know. Try to equate this to water. You have volts, amps, and ohms. Volts is the amount of water, amps is how much pressure the water is giving, and ohms is resistance - i.e. a straw. All alternators put out roughly the same amount of volts (water), but as time has progressed, more systems need the same required amount of water, thereby needing an increase in pressure to supply them. Where ohms/resistance comes in is when you have a bottleneck, such as how much pressure a certain piece of equipment needs or how small of a wire you're trying to feed that piece of equipment to. This is why you'll want a heavier gage wire for things that take a lot of amperage, so that wire doesn't impede the flow of volts. So, by upgrading from, let's say a 65 amp alternator to, say, a 95 amp alternator, you're ensuring there will be enough pressure (amps) to feed all of your bottlenecks so they all have the adequate amount of volts.
Hopefully this makes sense and helps steer you in a good direction. I'll let whomever wants to correct me and/or re-explain if it doesn't make sense.
Best of luck my friend!
My Opinion, I'm not a trained tech but just have 'old guy' experience, if the ride is stock, you will not be adding any Christmas lights, police siren or boom'n stereo leave it alone.
Yes, the charging system is barely able to keep up stock but it does keep up.
Keep a good battery and clean connections and you'll be trouble free for years.
We have a tech/how to forum here too.
If anything should be updated it would be the battery cables (+ and - ) and the starter cable, just one size larger will do, I do this on all my 'hot rods'.
I documented this in my adventure with fix'n stuff on the Junk Pyle.
Link at the bottom of my post.
If it's still there
Yes, the charging system is barely able to keep up stock but it does keep up.
Keep a good battery and clean connections and you'll be trouble free for years.
We have a tech/how to forum here too.
If anything should be updated it would be the battery cables (+ and - ) and the starter cable, just one size larger will do, I do this on all my 'hot rods'.
I documented this in my adventure with fix'n stuff on the Junk Pyle.
Link at the bottom of my post.
If it's still there
Thanks for that, I’ll definitely add it to my list. I do have a sizable amp and two kickass sundowner 10’s that fill up my trunk. Man, I’m 52, graduated in 91 and I got the car I always wanted but couldn’t afford until I ran across this gem two years ago. Yeah, I’m making it just like I would have back then, but better. I’m really thinking a lot of my codes will go away with a new bigger alternator and voltage regulator. It runs fantastic, but the battery doesn’t charge well enough just cranking it once a week and letting it idle. It definitely needs more juiceMy Opinion, I'm not a trained tech but just have 'old guy' experience, if the ride is stock, you will not be adding any Christmas lights, police siren or boom'n stereo leave it alone.
Yes, the charging system is barely able to keep up stock but it does keep up.
Keep a good battery and clean connections and you'll be trouble free for years.
We have a tech/how to forum here too.
If anything should be updated it would be the battery cables (+ and - ) and the starter cable, just one size larger will do, I do this on all my 'hot rods'.
I documented this in my adventure with fix'n stuff on the Junk Pyle.
Link at the bottom of my post.
If it's still there
On my OBD 1 with the “key on engine off” test I’m getting codes: 10, 11, 31 and 96. Referencing the charts in the book. I replaced the fuel pump relay already, but still getting the code. I’m just trying to get all the codes cleared where I can run the “engine running” test. Watched several YouTube about these and they all seem to have a different cause. I know the 31 code is the riddle of everything because it has several different things listed in the book.
If the amp you have has the wattage to really drive those two tens then I would suggest an upgrade to a 150A 3G. I would also suggest you up your battery game to one with at least 800 CCA. You will need to run a 4ga power wire from the alt to the starter solenoid and a 4 ga power wire from the battery to the same side of starter solenoid. I would suggest you upgrade the ground wire from the battery to the frame and frame to engine block. From there run the appropriate sized power wire to the amp (if you have not already) and you should be good to go.
I would do the 3g. I used a 130a PA performance kit on mine from LMR. It's been totally trouble free.
The original 2g's barely keep up. If you do short tips, or have any extra accessories it won't keep up. Even when these cars were new they were having charging system problems. The dealer I worked at in the 90's was always getting vehicles (with 2g charging) towed in for dead batteries and melted alternator connectors. The biggest issue with 2g is all the amperage is transmitted back to the battery with undersized wiring and undersized wiring terminals inside the plastic alternator connection plug. The connection melts and ruins the plug as well as the alternator. If there is a constant draw, like an amplifier or electric cooling fan it makes it unsafe IMO. Google "2g alternator fire".
The 3g gives you a post terminal for this connection allowing a high amperage connection and allowing heavy wiring back to the battery (solenoid post).
You'll be happy you did the 3g conversion. No reason to worry about deviating from stock here. IMO it's a necessary improvement.
If you take your time routing the heavy 4ga power cable you'll never even know it's there. A good spot is to drop the new cable down from the alternator to the harness that runs under the front of the engine just behind the crankshaft balancer pulley. That harness is secured to the two longer front oil pan studs. This is also where the battery negative cable runs to the engine block. You can run your new power cable along side with that and follow it back up to the battery area. I feel it's a much better location than shoving it between the radiator and condenser which is what the instructions said.
The maxi fuse fits nice behind the factory plastic ignition coil cover.
Good luck with it!
The original 2g's barely keep up. If you do short tips, or have any extra accessories it won't keep up. Even when these cars were new they were having charging system problems. The dealer I worked at in the 90's was always getting vehicles (with 2g charging) towed in for dead batteries and melted alternator connectors. The biggest issue with 2g is all the amperage is transmitted back to the battery with undersized wiring and undersized wiring terminals inside the plastic alternator connection plug. The connection melts and ruins the plug as well as the alternator. If there is a constant draw, like an amplifier or electric cooling fan it makes it unsafe IMO. Google "2g alternator fire".
The 3g gives you a post terminal for this connection allowing a high amperage connection and allowing heavy wiring back to the battery (solenoid post).
You'll be happy you did the 3g conversion. No reason to worry about deviating from stock here. IMO it's a necessary improvement.
If you take your time routing the heavy 4ga power cable you'll never even know it's there. A good spot is to drop the new cable down from the alternator to the harness that runs under the front of the engine just behind the crankshaft balancer pulley. That harness is secured to the two longer front oil pan studs. This is also where the battery negative cable runs to the engine block. You can run your new power cable along side with that and follow it back up to the battery area. I feel it's a much better location than shoving it between the radiator and condenser which is what the instructions said.
The maxi fuse fits nice behind the factory plastic ignition coil cover.
Good luck with it!
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If you do 150g, you will need to make sure your wiring size is adequate. 3G 130A alt from a 94-95 is pushing the limits of the 4g wire, so you will need to likely go with #2 and fuse for the wire.
