[highrisk]

I am adding dual fans to the car and at the same time I am replacing my 94 amp alternator with a 150 amp to handle the 50 amp requirements of the fans. As part of this I am upgrading my ground wire to 2 gauge and running a 2 gauge wire from the alternator to the battery. My question is what to do with the stock wire that connects to the back of the alternator and runs to a junction and then to the starter. Will it hurt to leave this connected to the alternator or should it get disconnected to prevent too high of a load going through it? I know it needs to stay connected at the starter because that wire provides power to the rest of the car. I was thinking of leaving it off at the alternator and capping it to prevent a short then the car can get its electric through the battery wire going to the starter.

Thanks for the advice,
Dale

[92GTA]

I go from the battery to a main junction, them from that junction to the starter and alternator. Just like in this video: https://www.youtube.com/watch?v=BQdQBesuJCs

[highrisk]

Originally Posted by 92GTA

I go from the battery to a main junction, them from that junction to the starter and alternator. Just like in this video: https://www.youtube.com/watch?v=BQdQBesuJCs

On this car it goes from the battery to the starter then a wire goes from the starter and then splits and one wire goes to the alternator and one to the junction box. Since I am going to run a wire direct from the alternator to the battery I was thinking I could disconnect the original wire at the alternator that comes from the starter. The side that connects to the starter has to stay there because it feeds the rest of the car.

Dale

[johnta1]

Since you're running a separate and bigger wire from alternator to the battery, you don't need the one going to the starter.
(the other wires from the firewall connector need to still be used)

[highrisk]

Originally Posted by johnta1

Since you're running a separate and bigger wire from alternator to the battery, you don't need the one going to the starter.
(the other wires from the firewall connector need to still be used)

Thanks, that is what I was thinking. I also did not want to overload the little stock wire.
Dale

["QUICK-SILVER"]

Originally Posted by highrisk

I also did not want to overload the little stock wire.
Dale

"Load" is your electronic accessories; ignition, lights, heater fan, etc... Stronger alternator doesn't change amp requirements for that stuff.
Meaning, the factory power supply wire to the inside, with engine running, could stay hooked up factory. That's along with your new BIG wire.

Power for the new fan relays will need to come from the new BIG alt to bat wire. Junction block would be nice for that.

Clay

[highrisk]

Originally Posted by "QUICK-SILVER"

"Load" is your electronic accessories; ignition, lights, heater fan, etc... Stronger alternator doesn't change amp requirements for that stuff.
Meaning, the factory power supply wire to the inside, with engine running, could stay hooked up factory. That's along with your new BIG wire.

Power for the new fan relays will need to come from the new BIG alt to bat wire. Junction block would be nice for that.

Clay

Thanks, I appreciate the information. Yes the fans and all of the added accessories will run off of the new 2 gauge wire. It is nice knowing I can leave the stock wire hooked up so I don't have to alter my new stock wiring harness.

Dale

[HWYSTR455]

I bolted a piece of angle iron to my batt tray for my junction point, using 5/16 studs, with short 4G SGT wire to the batt posts.

I have a 4G GXL wire going from the NEG junction post to the frame, using a thread-sert in the frame, then to the engine block (spare engine mount bolt hole).

My ALT is a 175a, with a bolt in the case & a 4G GXL wire down to the same point the GND is attached. The output post I ran 4G GXL wire to a Ford Sol on the firewall, then to the POS junction post on the batt tray.

6G GXL power wire from Ford Sol to the starter.

Everything else go to the junction posts for power & ground.

I have a 6G GXL wire with thread-serts in the frame to the cowl mount at the body mount, and one in the rear from the frame going to the rear inner wheel house.

No welding wire. I use ONLY SGT, GXL, and in some high heat areas, TXL wire. It's affordable, and WireBarn.com has great prices, and you can buy by the foot.

ONLY quality connectors, and proper crimps. I prefer nickel coated ring terminals and eyelets. WayTekWire.com is your friend.

I use only Metri-pack, Delphi/Aptiv, AMP, or like connectors for sub-harnesses and such, with proper crimps. All are spec'd for proper amp of connection(s). Converted most of the engine, forward lamp, and rear harnesses to weatherpak or metri-pack connectors.

https://www.waytekwire.com/products/1598/Connectors/

My dual 12" fans are 28a max each, and wired separately using Metri-pack 480 connectors.

I used a combo of expandable nylon mesh cover and split mesh cover.

It takes time and can be costly to do it right, but you only have to do it once.

.

[HWYSTR455]

Wire gauge, length, and amp sizing calculator:

https://www.wirebarn.com/Wire-Calculator-_ep_41.html

You should have no more than a .05v drop over the length of a feed or ground wire.

.

[highrisk]

Originally Posted by HWYSTR455

I bolted a piece of angle iron to my batt tray for my junction point, using 5/16 studs, with short 4G SGT wire to the batt posts.

I have a 4G GXL wire going from the NEG junction post to the frame, using a thread-sert in the frame, then to the engine block (spare engine mount bolt hole).

My ALT is a 175a, with a bolt in the case & a 4G GXL wire down to the same point the GND is attached. The output post I ran 4G GXL wire to a Ford Sol on the firewall, then to the POS junction post on the batt tray.

6G GXL power wire from Ford Sol to the starter.

Everything else go to the junction posts for power & ground.

I have a 6G GXL wire with thread-serts in the frame to the cowl mount at the body mount, and one in the rear from the frame going to the rear inner wheel house.

No welding wire. I use ONLY SGT, GXL, and in some high heat areas, TXL wire. It's affordable, and WireBarn.com has great prices, and you can buy by the foot.

ONLY quality connectors, and proper crimps. I prefer nickel coated ring terminals and eyelets. WayTekWire.com is your friend.

I use only Metri-pack, Delphi/Aptiv, AMP, or like connectors for sub-harnesses and such, with proper crimps. All are spec'd for proper amp of connection(s). Converted most of the engine, forward lamp, and rear harnesses to weatherpak or metri-pack connectors.

https://www.waytekwire.com/products/1598/Connectors/

My dual 12" fans are 28a max each, and wired separately using Metri-pack 480 connectors.

I used a combo of expandable nylon mesh cover and split mesh cover.

It takes time and can be costly to do it right, but you only have to do it once.

.

Thanks for all of the great information. I like what you did with the battery box, great idea.
Dale

[HWYSTR455]

You really should use a PWM controller with electric fans, there are a number of them out there. Just look for ones that are waterproof if you plan to run it in the engine compartment.

This guy makes some really good ones, and was going to use one on my next project.

https://www.autocoolguy.com/

Someone here mentioned them to me, looked into them, and feel they are well made, and have great features. I was looking at the DX-150, which has solid state relays built in, which saves on additional wiring and relay costs.

.

[92GTA]

100% on PWM. I run a controller from this place for my EWP and fans:

http://www.dccontrol.com/constant_te...ontrollers.htm

[Lee]

HWYSTR455 and 92 GTA provided some excellent advice, and they think a lot like I do on these subjects.

That said, have you wondered why the factory didn't save a bunch of wire, and go straight from the alternator to the battery??? It is bad for the battery.

Run the 2ga. from the alternator to the starter, then the battery cable can return the voltage to the battery. I'd leave the stock wire to power everything else.

[george kujanski]

Lee...kind of off topic, but I think the OEM figured it the following way.....the BAT cable needed to go to the starter anyway, and they needed a connection point for the alt cable...there you have it.

In what way would the previous setup be bad for the battery?

george

[Lee]

Originally Posted by george kujanski

Lee...kind of off topic, but I think the OEM figured it the following way.....the BAT cable needed to go to the starter anyway, and they needed a connection point for the alt cable...there you have it.

In what way would the previous setup be bad for the battery?

george

George, you know WAY more than I do about electrical topics! The person that that convinced me that there was a reason for the alt-bat wire to be longer was also way more versed than myself.

I remember the point of the lesson better than I do the reason, but basically it came down to heat. Between less voltage drop with a short wire, and conducting heat from the alternator, too much heat COULD be introduced to the battery. Running a 8-10' wire was what he insisted was proper, to connect the alternator to the battery.

[highrisk]

Originally Posted by HWYSTR455

You really should use a PWM controller with electric fans, there are a number of them out there. Just look for ones that are waterproof if you plan to run it in the engine compartment.

This guy makes some really good ones, and was going to use one on my next project.

https://www.autocoolguy.com/

Someone here mentioned them to me, looked into them, and feel they are well made, and have great features. I was looking at the DX-150, which has solid state relays built in, which saves on additional wiring and relay costs.

.

Since I have the Holley Sniper EFI I am letting the EFI system provide the signals to turn on the fans. I used these wiring harnesses for each fan, https://www.summitracing.com/parts/aww-500479, and used these circuit breakers instead of the provided fuses, https://www.summitracing.com/parts/aww-500667. This is the fan kit I installed, https://www.summitracing.com/parts/der-16825, and this is the alternator I used, https://www.summitracing.com/parts/pwm-47294. It was tested at 108 amps at idle, 128 amps at cruise, and at 162 amps maximum.
I have fan #1 set to come on whenever the A/C is on or when the temperature gets to 180°. The #2 fan comes on at 190°, or when the A/C pressure gets to 254lbs from the A/C trinary switch, it is also on a manual switch and I can turn it on at any time. Last weekend we took a Sunday cruise to our favorite orchard for some peach cobbler and ice cream. It was in the low 90's and very humid with a heat index over 100°. On the way home we got stopped at a railroad crossing for about ten minutes and I let the car idle with the A/C on and the car's temperature never went above 180° to 185°, the #2 fan never had to turn on. Before the electric fan upgrade I would have had to shut the car off to keep it from overheating.
The project was very time consuming to run all the wires, rewire a lot of items to work with the fans, paint the fan shroud to match the radiator, and make the brackets to install the fan and shroud, but it was worth every minute of time and a few cuss words. Now I never have to worry about the car overheating and I have an alternator that can handle it all.

Thanks for all of the advice and help,
Dale

[HWYSTR455]

Originally Posted by highrisk

Since I have the Holley Sniper EFI I am letting the EFI system provide the signals to turn on the fans. I used these wiring harnesses for each fan, https://www.summitracing.com/parts/aww-500479, and used these circuit breakers instead of the provided fuses, https://www.summitracing.com/parts/aww-500667. This is the fan kit I installed, https://www.summitracing.com/parts/der-16825, and this is the alternator I used, https://www.summitracing.com/parts/pwm-47294. It was tested at 108 amps at idle, 128 amps at cruise, and at 162 amps maximum.
I have fan #1 set to come on whenever the A/C is on or when the temperature gets to 180°. The #2 fan comes on at 190°, or when the A/C pressure gets to 254lbs from the A/C trinary switch, it is also on a manual switch and I can turn it on at any time. Last weekend we took a Sunday cruise to our favorite orchard for some peach cobbler and ice cream. It was in the low 90's and very humid with a heat index over 100°. On the way home we got stopped at a railroad crossing for about ten minutes and I let the car idle with the A/C on and the car's temperature never went above 180° to 185°, the #2 fan never had to turn on. Before the electric fan upgrade I would have had to shut the car off to keep it from overheating.
The project was very time consuming to run all the wires, rewire a lot of items to work with the fans, paint the fan shroud to match the radiator, and make the brackets to install the fan and shroud, but it was worth every minute of time and a few cuss words. Now I never have to worry about the car overheating and I have an alternator that can handle it all.

Thanks for all of the advice and help,
Dale

That's good Dale, and nice install. I like those AWW relay holders, because they have a mounting tab, and you don't have to take a screw out to change the relay.

Reason I say one should use a PWM controller is multi. One, the fan(s) don't come on at 100% all at once, which can introduce a power surge, and over time can cook the regulator in the alt.

Another reason is that a PWM ramps up fan RPM as heat goes up, or at a pre-determined ramp from 0-100%. That too prevents excessive loads on the harness and alt.

I use the same setup as you on the 442, but have capacitors for the stereo, which helps manage the load shock. That helps the regulators live. I also used to have the same setup on my LeMans, without caps, and that used to cook alts frequently. (Can search for my previous threads over the years). Somehow, it does work adding caps. And you don't need a big stereo to get benefits from adding one.

Now, on the new build, I run a pair of 'vette OE GM PWM controllers, and a PWM signal from the Holley ECU (Dominator). I have full control of the ramp and fan speeds.

I will do that on the 442 as well, it has an original Terminator tbi setup on it, which uses the HP ECU.

I wish Holley would add a PWM output to the Sniper models, but guess it's supposed to be an entry level setup, and the added cost makes it less marketable.

One suggestion on your setup, may want to baffle the core/radiator areas so it doesn't suck engine bay heat to pass the radiator core. The hot water heater foam 'noodles' work very well, and are available in black. They form with a little heat, and don't hold water.

As for the ALT and BATT POS cables to the starter, one, that tube for the wires between #5 & #7 exhaust ports may not be able to hold another thick wire, and two, there's a ton of heat there. The remote solenoid trick for hot starts provides benefits more than just for hot starts, it prevents the charge wire from creating additional resistance from heat.

Also remember, over distance, a wire adds resistance. So once you go beyond X number of feet, you may need a larger gauge. (look at the calculator I provided the link to above for more info).

If you have more than the recommended .05 volt drop over the distance of the charge wire, or any circuit for that matter, it puts excessive load on the regulator, and the stator. That cooks ALTs.


.

[highrisk]

Originally Posted by HWYSTR455

That's good Dale, and nice install. I like those AWW relay holders, because they have a mounting tab, and you don't have to take a screw out to change the relay.

Reason I say one should use a PWM controller is multi. One, the fan(s) don't come on at 100% all at once, which can introduce a power surge, and over time can cook the regulator in the alt.

Another reason is that a PWM ramps up fan RPM as heat goes up, or at a pre-determined ramp from 0-100%. That too prevents excessive loads on the harness and alt.

One suggestion on your setup, may want to baffle the core/radiator areas so it doesn't suck engine bay heat to pass the radiator core. The hot water heater foam 'noodles' work very well, and are available in black. They form with a little heat, and don't hold water.

As for the ALT and BATT POS cables to the starter, one, that tube for the wires between #5 & #7 exhaust ports may not be able to hold another thick wire, and two, there's a ton of heat there. The remote solenoid trick for hot starts provides benefits more than just for hot starts, it prevents the charge wire from creating additional resistance from heat.



.

Thanks for all of the great information and complement, it was a lot of hard work and planning. I already have insulated the radiator/core area so the fans only suck air through the radiator. I used the FrostKing foam strips for insulating around window A/C units. They seem to work really well and compact well for stuffing them into cracks. If I find I need to make changes in the future I will definitely look at the PWM product. I like the idea that they bring on the fans slowly to reduce the load. I don't run the wires down through the original tube, I use the one from the 67 that runs under the exhaust. I also ground to a bolt hole in the front of the left head which works well. I ground the battery there and run an extra ground wire from the alternator. I have kept all of the wires as short as possible with the longest wire being the one that goes from the battery to the starter which is routed down pass the steering box, along the frame and engine block to the starter solenoid to avoid the really hot areas where the original wire was ran. It is also heavier than stock for the increased loads and the high torque starter.

Thanks again,
Dale

[HWYSTR455]

Yeah that all sounds good, and routing the POS cable along the block to the starter is a good idea. Head is a fine ground point too, just make sure it's paint free.

Was it you that mentioned you are using the PowerMaster 47294 ALT? That's my go-to 12si ALT, have used that one for years and have very good service out of those. Use them on all my v belt cars. Just make you have the correct belt tension, too loose and it will slip and cook the belt and front bearing, too tight and it will cook the front and rear bearings.

Frost king stuff works good, but sometimes you have to build it up to fill bigger gaps, and can get sloppy. Not sure how those are with heat either. But stuff like that, yeah, you've got the idea.

PowerMaster recommended charge wire gauge for X amp and X distance:

http://www.powermastermotorsports.co...e_wires_a.html

Here's the eyelets I use, tinned copper, generally the 5/16 hole/post type:

https://www.waytekwire.com/item/3656...Eyelet-36565-/

All the tinned copper eyelets:

https://www.waytekwire.com/products/...=Tinned-Copper

Hyd terminal crimper:

https://www.amazon.com/Hydraulic-Bat.../dp/B06XR8BY65

I have this manual one, can be awkward at times but works, and under $30:

https://www.amazon.com/IWISS-Termina...13145091&psc=1

Rivet-Nut tool, this one only goes to 5/16, but you will mostly use #10, 1/4, and 5/16 anyway:

https://www.amazon.com/dp/B07XT5PF69...NsaWNrPXRydWU=

You could get one that goes to 3/8, but they get a little more pricey when the nuts get bigger.

They make a large contact area, which is great for grounds, and you will find many other uses for them too. Great to have, you would be surprised.


.

[highrisk]

Originally Posted by HWYSTR455

Yeah that all sounds good, and routing the POS cable along the block to the starter is a good idea. Head is a fine ground point too, just make sure it's paint free.

Was it you that mentioned you are using the PowerMaster 47294 ALT? That's my go-to 12si ALT, have used that one for years and have very good service out of those. Use them on all my v belt cars. Just make you have the correct belt tension, too loose and it will slip and cook the belt and front bearing, too tight and it will cook the front and rear bearings.

Frost king stuff works good, but sometimes you have to build it up to fill bigger gaps, and can get sloppy. Not sure how those are with heat either. But stuff like that, yeah, you've got the idea.

Here's the eyelets I use, tinned copper, generally the 5/16 hole/post type:

https://www.waytekwire.com/item/3656...Eyelet-36565-/

All the tinned copper eyelets:

https://www.waytekwire.com/products/...=Tinned-Copper

Hyd terminal crimper:

https://www.amazon.com/Hydraulic-Bat.../dp/B06XR8BY65

I have this manual one, can be awkward at times but works, and under $30:

https://www.amazon.com/IWISS-Termina...13145091&psc=1

The heads are aluminum so I don't have to worry about paint interfering with the ground.
Yup, I am the one that mentioned the PowerMaster alternator. I did a lot of research and it seemed like the best alternator for the money and did what I was needing. I adjusted the tension as per the instructions on the alternator and I get no belt slip. I also gutted and rewired the original external regulator so I can run the 12si internal regulated alternator and still use my new, stock wiring harness.
The FrostKing insulation comes as big as 2" square so it can fill some pretty big holes and is very easy to work with. It also comes in a lot smaller sizes for smaller holes.
I used the tin covered copper terminals too. I ordered mine from Amazon in a kit with multiple sizes. Probably not as nice as yours but they seemed good quality. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Thanks for the crimper recommendation I like the hydraulic one and might order it. I had actually ordered the IWISS manual one from Amazon and after it not shipping for 2 weeks I canceled the order and used an old crimper and also soldered the terminals for a solid connection.
Thanks again,
Dale