944 / 968 battery cables

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Ajay213
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dcmachinist wrote: Sun Jul 09, 2023 7:30 am I've got two hydraulics in different sizes and I rarely use them. I prefer mechanical crimpers because I can feel the pressure much better and they are MUCH faster. Someone will want it though. Hydraulic is nice for really large lugs but I rarely crimp over 1 gauge. I use a telescopic Temco for my 1 and 2 gauge and an old Thomas and Betts WT115 for my 4 and 6 gauge.
Yea, I can see that, I have hydraulic as well, and it's not fast in any way to crimp an end on - both the 'fiddly'ness of trying to hold everything in the right place and then the actual hydraulic pumping to do the crimp, but it was relatively affordable, and the quality of the crimps are top notch.

It is interesting to see how the tools have changed over the years though, there was a time that the only option for doing 'large' gauge (in the auto world) crimps was to use a hammer (or if you were fancy a hammer crimper) as the crimp tools cost many hundreds of dollars and weren't that good. Or you took your wire/terminals to somebody who had the tools and begged/bribed to use them.
cp99 wrote: Mon Jul 10, 2023 5:06 am Thanks. What gauge are the factory 968 cables?
I don't know the 968, but the (later) 944 cables aren't that big, the cables are all in metric, but they work out to being 2 ga for the battery/starter cable and about 6ga for the alternator/starter cable. I gave up on the 1ga battery cable, it was just too stiff to run around, and went back to 2ga...I did leave the 4ga for the alternator cable, but it was flexible enough.

Given the current draw and lengths, those are more than adequate to handle the loads the car will normally encounter. Now the routing in some cases is a little suspect, and then a modern cable will have better sheathing, plus you can run the cable in more protective sleeving. The biggest problem I've seen with the cables is simply them aging out, everything gets brittle after that many years, the ground cables that came out of my car, the sheathing was breaking apart in my hands. The power side was still in relatively good shape (thankfully). The other 'problem' is you never know who did what in the cars past, and 944's are notorious in the P-car world for having some janky repairs done to them, so always worth checking out what was done.

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mwc951
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I put the hydraulic crimper in a vice.
No "fiddlyness".
If I were in a hurry, I wouldn't DIY.
So I don't factor in the length of time to do the job. It's relaxing (usually), and I enjoy being able to be as anal as I want.
As well, I want to use my own cable, as flexible or as stiff as I choose. I've purchased in the past, the power cable was way too stiff. These I just finished are the 3rd set I've made.

#32

dcmachinist
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They are 35mm^2 which is about two or three percent more copper than 2 AWG if I remember correctly. It's been a few years since I looked it up.

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dr bob
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Don't know if this helps--

I made the positive cable for my car, using some Ancor 1ga marine battery cable. It's fine-strand tinned copper, and the outer jacket diameter is about the same as the 2.xx ga original cable. Ends are crimped (starter end) and soldered (battery post end) with heat shrink. Wire came from the local West Marine, not cheap but handy. Getting the diameter right is important on the 928 anyway since the cable is supported in P clamps from the rear battery. Don't know how the 944 cables are routed so the diameter may not be as important.

Tangent --
The symptom I was chasing was a charging issue. The problem tuned out to be some corrosion in the battery ground strap, which had a shrink sleeve over the braided copper. Replaced that with 2-ga rated tinned copper strap and some heat shrink. The tin coating protects the copper conductors, and makes it very easy to solder terminals and clamps when you need to.

On the 928 the positive cable is routed under the left exhaust at the steering rack. Originally there's a protective sleeve there, mostly for mechanical/abrasion protection. A piece of black 1/2" PVC repair tubing from Home Depot just barely fits over the 1ga Ancor cable I used. If your cables pass near a bit of heat or need mechanical protection, get creative. So far 10+ years) so good on mine.
dr bob

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Ajay213
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mwc951 wrote: Mon Jul 10, 2023 7:47 am I put the hydraulic crimper in a vice.
No "fiddlyness".
If I were in a hurry, I wouldn't DIY.
So I don't factor in the length of time to do the job. It's relaxing (usually), and I enjoy being able to be as anal as I want.
As well, I want to use my own cable, as flexible or as stiff as I choose. I've purchased in the past, the power cable was way too stiff. These I just finished are the 3rd set I've made.
Sure, I'm with you, I enjoy the journey and the destination when it comes to cars (and honestly I think I like working on them more if given the choice).
dcmachinist wrote: Mon Jul 10, 2023 8:12 am They are 35mm^2 which is about two or three percent more copper than 2 AWG if I remember correctly. It's been a few years since I looked it up.
Yep, my mistake, I thought they were just under, but I just looked it up, and they are just over 2ga.
dr bob wrote: Mon Jul 10, 2023 8:54 am Don't know if this helps--

I made the positive cable for my car, using some Ancor 1ga marine battery cable. It's fine-strand tinned copper, and the outer jacket diameter is about the same as the 2.xx ga original cable. Ends are crimped (starter end) and soldered (battery post end) with heat shrink. Wire came from the local West Marine, not cheap but handy. Getting the diameter right is important on the 928 anyway since the cable is supported in P clamps from the rear battery. Don't know how the 944 cables are routed so the diameter may not be as important.
Ancor cable isn't a bad choice at all, I did the same thing for most of mine as well. The only thing that is 'bad' with it is that it isn't the most flexible stuff out there. ABYC standards are pretty stringent.
dr bob wrote: Mon Jul 10, 2023 8:54 amTangent --
The symptom I was chasing was a charging issue. The problem tuned out to be some corrosion in the battery ground strap, which had a shrink sleeve over the braided copper. Replaced that with 2-ga rated tinned copper strap and some heat shrink. The tin coating protects the copper conductors, and makes it very easy to solder terminals and clamps when you need to.

On the 928 the positive cable is routed under the left exhaust at the steering rack. Originally there's a protective sleeve there, mostly for mechanical/abrasion protection. A piece of black 1/2" PVC repair tubing from Home Depot just barely fits over the 1ga Ancor cable I used. If your cables pass near a bit of heat or need mechanical protection, get creative. So far 10+ years) so good on mine.
Wiring corrosion is a big deal on cars this old, so it should always be kept in mind. For all the cables I made that went into the engine compartment, I wrapped them in mostly-fire-proof-mostly-chemical-proof sheathing (Tech-flex makes a huge array of different products), I don't want the exposure/liability of selling something, but I think I'm pretty well covered as well, but in the NA 944 none of the cables really run anywhere problematic.

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mwc951
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Ajay213 wrote: Mon Jul 10, 2023 2:49 pm Wiring corrosion is a big deal on cars this old, so it should always be kept in mind.
For sure!
Given the engine harness in my car is 35 years old and hacked up with a SMT6 & various Lindsey sub harnesses...
I just finished installing a Kroon engine harness. Somewhat of a nerve-racking job, for the most part a straight forward install and plug & play. I can say the car has never started & idled as smoothly as it has with the new harness.
I would HIGHLY recommend the Kroon harness if anyone is considering an engine harness.

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Ajay213
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mwc951 wrote: Mon Jul 10, 2023 3:02 pm For sure!
Given the engine harness in my car is 35 years old and hacked up with a SMT6 & various Lindsey sub harnesses...
I just finished installing a Kroon engine harness. Somewhat of a nerve-racking job, for the most part a straight forward install and plug & play. I can say the car has never started & idled as smoothly as it has with the new harness.
I would HIGHLY recommend the Kroon harness if anyone is considering an engine harness.
There are a few NOS OEM harnesses around, it's tempting for sure....of course I just had the engine apart, but I may buy just to put on a shelf for the next time everything is apart. I've gone around and cleaned/re-grounded everything (new hardware, wirebrush, etc...then coated in dialectric where appropriate), it helped in a few places and shockingly was about the same in others (I measured resistance before/after).

#37

dcmachinist
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cp99 wrote: Thu Apr 13, 2023 3:57 am
stitch2k1 wrote: Wed Apr 12, 2023 9:42 pm Yeah I saw he was starting to make stuff again. I intend to grab a set.
You cannot make what he does for the price he sells it for. Installed a set before on a car, good stuff.
Where is he selling the cables?
https://www.dcmachinist.com

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Jay Wellwood
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I spoke with this guy a few weeks ago, He's still in the game.

https://www.dcmachinist.com/
Jay

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Bergerac
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dstupakov wrote: Thu May 04, 2023 11:22 am Sure thing - here's the alternator harness I just got and where it plugs into on the firewall side.

Looks painfully similar to a standard 2 pin molex, but just a bit different.

Probably easier to just cut it off and go to a 2 pin DTM connector.
Did anyone end up finding a source for this plug? dcmachinist wont ship overseas so I'm making my own harness

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