tyrant

I just installed my Dewitt's radiator in my '68. I am running a unit for a '69. It has no air no power options at all. I will be putting in electric headlight motors. I have read post after post attempting to learn as much as possible but post of the posts are older and missing picture links. On to my questions/observations.

I currently have no generator so I am looking at upgrading I believe 100 amp will do it along with bypassing the external regulator. From what I've gathered I need to increase the wire gauge from the alternator to the starter. 8awg? Maybe install a junction on the firewall to run the headlight power as well.My temperature sensor is in the radiator. So both grey wires to that. Power to starter or battery. Trigger to ignition on the fuse panel. And ground to the frame.
I would like to see any pics on wiring routes if possible. Looking forward to your input.

ignatz

Your ammeter readings likely will no longer make sense when the fans kick on. I converted it to a voltmeter. Pluses and Minuses on that score.

My car is a 69 w/o A/C. I also installed a 100 amp alternator. No problems. I am considering a PWM controller for the fans as they are hellaciously noisy when they kick full on. I think something in between off and on will keep the temperature a bit more constant.

tyrant

What alternator did you use?

cv67

id be interested in a controller also dont care for those probe types they dont seem real reliable. All ears...

Been wondering if a HD late model GM fan is the way to go, very powerful & never seen one go out. OEM stuff seems to last forever
If it can keep a heavy truck with AC cool should do great on a C3

The C7s have a nice brushless setup think pauldana has something like that. Once they come down to earth on price may consider;dont mind an electric but not a fan of the temp fluctiations

ignatz

There's already an older thread on this which is what got me interested. I don't have a reference for you, though.

ignatz

It's chrome from Summit. Sticker on top says

17-05-13
17294-114
WC

Guessing that's 114 amps. Conventional wiring, not single wire. Instructions came with an RPM limit as I remember. Let me know if this doesn't get you to it, I probably have the instructions somewhere.

tyrant

It looks like I could get a 140 amp for a bit more. I am going to upgrade to a 8 gauge wire are there any negatives in a 140? I see some are happy with there 80.

Street Rat

I've got a Spal dual fan setup which I haven't installed yet. I purchased a PWM controller and a 140amp Powermaster alternator too. Upgraded the battery cables and alternator wires to 0 gauge. I went ahead and installed the alternator prior to the fan install. Looking forward to getting this done soon.

lionelhutz

If you don't care about original looking, then I would use a CS-144 alternator. In stock form it can output more current then many of the worked-over aftermarket 10SI alternators can. The maximum current rating doesn't mean too much. What is important is the idle output current capability.

I would use a 6 gauge wire from the starter to the alternator.
Put a 10 gauge fusible link at the starter end to protect it.
Put a good junction block somewhere in the run if you want to have a convenient spot under the hood to connect the accessories.

If you do install a junction block,
Connect the voltage sensing wire from the alternator to the junction block.
Re-do the existing main wiring so that the main interior feed wire going to the firewall connector runs from the junction block.
You'll need to run a wire to the horn relay so the horns work. You could get away with 14 gauge to just power the horns.
Put fusible links on the above wires at the junction block. Use 2 wire sizes (example #14 for 10 gauge wire) higher for the fusible links.

7T1vette

If you just ADD another parallel power line from the alternator to the battery (while keeping the original wire), your ammeter will still function...but the calibration will be different. If you add the SAME size wire that is installed presently, the ammeter will read about 1/2 of the actual current being drawn. That should also give you plenty of capacity for the electrical circuits. You would also want to install a fusible link in that line or a circuit breaker of appropriate size.

If I were doing that job, that's would I would do. {And I might also replaint/re-number the ammeter dial so calibration would be approximately correct.}

tyrant

Just trying to get this right in my head. I was originally going to run a 8 gauge from the alternator to the starter lug.i was also going to run a 4 gauge to a junction lug to run my fans/ headlight motors off of. You are suggesting 6 gauge instead of 8 gauge which in any case would be a safer bet.take the power wire from the horn relay and run it to the junction box to power the interior. Then run a 14 gauge power back from the lug to the horn relay.I am still looking into alternator replacements. My inlaws own a recycling yard. There are literally hundreds of alternators to try out to see how they fit. Do the c144 bolt right up with existing brackets? Also trying to source a good junction box. Can not find locally.

tyrant

I have also seen that the method you are suggesting seems to work as well and will keep the original gauge. Does this method change with alternator choice?

lionelhutz

Yes, you can just run the wire from alternator to a junction block and then from it to the starter. The junction block gives you the place to power the interior and the new accessories. Connecting the voltage sensing wire to that block will allow the alternator to maintain the voltage at that block.

Right now, the horn relay is the main junction block. But, if you install a new junction block then you'r removing the stock wire from the starter to the horn relay so the horn relay is now "dead ended". You can either jumper from the new block to the horn relay with 10 gauge or move the wire that powers the interior to the new junction block. If you move the wire then you just need to provide enough power to the horn relay to run the horns which 14 gauge would do.

Look at the firewalls on 90's GM cars or pickups. You can likely find a good junction block there.

I don't believe they all will, but there are CS-144 alternators with similar mounting tabs to your 10SI alternator and they will bolt right in.

tyrant

I ordered some 8 gauge on line can't find it local. I'll look for some 6 gauge tonight. I will hit the u pull it this weekend for a junction box. I'll keep you posted. Thanks for your help.

wendellp601

I'm using this controller from Flex-a-lite to run my electric fan.
This model uses a screw in temp sensor that I installed into my intake manifold. It features a "soft start" and also runs for about 30 seconds after shutdown.

https://www.summitracing.com/parts/flx-31163/overview/

tyrant

Will 8 gauge cut it for the alternator? 6 is not as easy to get in the lengths I need and my crimper wouldn't cut it. I did find two 7' lengths of 6 gauge with ends already installed.

tyrant

Spent a few hours in the local u-pull it. Scored a junction box and 15' of wire out of a BMW and a good 140amp cs144.

mrvette

The alt upgrade is a good move, not that you will ever use that capacity, but I would hope you have a serp drive on your engine, changing the pulley will be ok for a time, but you have to make sure you have the old style V belt in there, not the later metric sized belts, the pitch of the V is different, and so the metric belts get to riding on the top of the V and so have less traction/more slip....

second thing, stay away from the stock wiring to the battery/car harness, just run a fused wire to the fan control device, a simple relay like I have or your PWM controller, which I consider overkill for a non existent problem.....

I routed my wire up and over top of the belts to the relay on the top of the radiator, nice a short and heavy with a 30 amp fuse in line....