gemellocattivo.com

I should probably just admit that a few products I worked on were a nylon co-polymer outer jacket that was welded to a ptfe inner jacket using FEP heat shrink tubing to compress the weld zone. We also did other similar operations using lower temp/force steps with the polyolefin stuff and different shrink ratios and such....so once upon a time I spent WAY too much time worrying about heat shrink tubing which the only reason this caught my eye.

one more post....here's a link to what the wire guy I use sells and he does have the Dr-25 and viton it looks like to go with the tefzel wire
https://www.prowireusa.com/c-9-heat-shrink-tubing.html

And now I see my mistake on the sleeve stuff...I bought the normal polyester not the much higher temp PET this guy sells

Then just because I think these things are amazing....heat shrink that solders on a ground lead for shielded wire as it shrinks and the red band vanished when its fully soldered. This is similar to the plastic welding we used to do but cooler cuz its metal.
https://www.prowireusa.com/p-1088-shiel ... -lead.html

I don't know that DR-25 necessarily needs to shrink... It's resistant to automotive chemicals and provides a barrier against chemicals and dirt getting into the harness. Mesh sleeving captures dirt and allows chemicals (and water and mud) through into the harness. If I install DR-25 with no intention of shrinking it, then finding places where it shrank tells me where I need to work on thermal management for my harness!

I haven't watched High Performance Academy's videos on wiring yet, but dressing harness with shrink tube and then shrinking it on the bench just seems like a way to make the harness stiff and difficult to install... which may account for emphasis on axial twisting in a lot of wiring circles.

I'm used to working on satellite wiring, which needs to stand 8-10 minutes of intense vibration in testing, then 8-10 minutes of intense vibration during launch... and is then good for the remainder of its service life.


I made a lot of good progress on the wire list yesterday... I ran out of time for the day, but I'm to the point at which I can start filling in prices and vendor links for connectors, connector accessories (TPA/"Secondary Lock", caps, lids, latches, Shorting Plugs, etc.--things that go according to the quantity of a given connector I use in the harness), terminals and terminal accessories (a convenient category that lets me use the same column as connector accessories... it's really just cable seals for terminals used in sealed connectors). I need to filter the list of terminals a little bit to be sure I'm not using one of one gauge of terminal when everything else is a different gauge... or if I am, there's a good reason.

I have more ground to cover on the wires. I can use the same spreadsheet magic to sort out unique combos of color and gauge, then count the instances of those unique combos. I'm sure I'll do a good bit of filtering here, as GM throws in a lot of striped wire that I don't really need. I will probably adjust the color codes on a circuit-by-circuit basis to make sure that I'm not ordering an entire spool of a particular combo for one circuit that's 14 inches long.

When the Great Wall was being built, a Chinese general contracted with an engineer to build one of the fortresses. The engineer designed the fortress, calculated how many bricks it would need, then placed an order for that many bricks. The general asked if the engineer should order a few more bricks, just to be safe. The engineer ordered one more brick. To this day, that brick sits on a table in the fortress.

That's my goal in this exercise... place ONE order with exactly what I need to build the harness from scratch to the maximum extent feasible.
However, that applies to the connectors, terminals and wire. I already expect that I will build and route the harness, THEN add up all the DR-25 that I'll need to dress it.

My stretch goal is to do all this well enough and plan out the system checks--like verifying fuel pump and relay function--that the engine starts and runs first crank.

just do it once? What fun is that?????

I don't know about the DR-25 but the FEP stuff we used had a shelf life because it would slowly shrink on the shelf until it was too small to use in our process so maybe just being in the engine bay for a few hours will shrink it for you? And if you are heat shrinking the entire harness please god don't let there ever be a need to repair anything if it does self shrink

Any news???

Lol... I wish. It's been a heavy summer & autumn.
In June I was in LA for two weeks for work, causing problems for Elon at SpaceX.
In July I had Covid and didn't have my voice back for pretty much the whole month
In August I was on Navy orders for 2 weeks
In September I was back in LA, causing more problems
In October I was going through the process of changing jobs
In November I was on Navy orders for another 2.5 weeks.
All the while trying to make progress on my kitchen remodel

Fortunately I have my final board for my big Navy qualification next week (I hope the Skipper's calendar holds for that) so that should free up time and head space to get back to the Northstar.

I have been able to steal a couple of full days to work on my spreadsheet of wire lists and harness bill of materials, which is almost complete. I learned a bunch of new spreadsheet-fu figuring out how to do that.

Anyway... I'm pretty sure I can get back to The Mule in January. I need to finish up my spreadsheet and order all the connector parts and wiring materials.

Always a shame when work gets in the way of the important things!

Good luck.

Back in action...
So I was wrong about January. What else is new?

I challenged myself to write a spreadsheet (actually using google sheets) that can turn my wire list directly into an orderable BOM.
I did that successfully... I'll probably share the spreadsheet soon, if for no other reason than to show off my code

There are 58 line items totaling 77 connector bodies and 56 line items totaling 513 terminals. I used the Mouser BOM preparation tool to build a "project" spreadsheet, then sent that out for quote to Mouser and Custom Connector Kits. CCK quoted a majorative subset at $177 for which Mouser wanted $275, so I went with CCK for that subset. The remaining 16 line items went to Mouser for $87.
There are a few things that neither company could get. I spec'd a splice saver connector for G202, along with a shorting plug with integral ring terminal. That shorting plug showed a >1 year lead time from Aptiv, but via the magic of the internet I found a third vendor with a small stash. I ordered 1 for $1, but then they added the small order fee to bring it up to $10 anyway :rolleyes:
I also found 1 vendor with 1 C500 connector body... for $50. Oh well, at least I'll have it.

I have not been able to source the ECM connectors. I need to try a little harder to find them on the internet. They are Molex MX123 family, but customized part numbers sold only to GM. The terminals are common and included in my initial order; only the connector bodies are difficult to get.

In copying GM's color codes, I ended up with 82 combinations of wire gauge, color and stripe. ProWire sells solid and striped TXL wire and I could have ordered all of those combos. They sell solid color wire in basically 1ft increments, while striped wire comes with a 100ft minimum and is ~50% more expensive per foot than solid color wire. I reorganized the color codes and found a few circuits with larger wire than they needed, ending up with 34 combinations of gauge and color, using only solid colors. I estimated the length I'd need based on the number of circuits for each combo and whether the circuits were long or short and placed the order. That came to ~$165 shipped.

So I'm pretty much at $500 in materials for the harness and still have to get a couple of things.

FieroGuru and Sinister both recommended 2007 Impala accelerator pedal assembly. That's available on RockAuto for $80ish.

Many years ago I got started on a firewall reinforcement plate to install between the pedal box and the firewall. It's meant to mitigate firewall flex at high pedal loads, thereby improving brake modulability. I can finish that design and weld coupling nuts to the plate at specific locations in order to both mount the pedal assembly AND incorporate a clutch pedal stop, which I will need, at least initially, for the dual disk clutch.

I have drill this weekend, but should be able to start crimping pins the weekend of 6/17.

Since I'm using the USCAR/EV6 injectors from the LC3 Supercharged Northstar, I need the appropriate connectors on the manifold harness. They're easy to get, but I haven't found part numbers for them yet. Of course I want the part numbers to add to my wire list so it's actually complete. I was looking through the service manual for my 2006 van for another item and happened across mention of Yazaki two pin connectors that looked suspiciously like EV6/USCAR injector connectors. Are USCAR injector connectors, ironically, Yazaki?

EDIT: Do I have to log in every so often to get topic reply notification emails? I have not received any, but there's been a lot of activity since the last time I was here.

Got a bunch of pins crimped this weekend!

I was off to a slow start because of having to organize everything required for this new phase of work, as well as digging up old parts--like the scratch-built A/C compressor fitting--that had been in boxes for months or longer.

Boxes of wires, connector parts and terminals:




Hello, my pretty... you're looking ravenous today




Apparently I need "extended reach" P-clamps to secure the harness in the manner that works in my head.




These are a pain, so naturally I have four of them:




First connector clicked!




Also trying to make the routing work like it does in my head:




Have just a few more line items to work through




CS130 alternator receptacle




And the plug on the harness side... that doesn't really look like it's the right one, but is.




The state I achieved at the end of the weekend:







Obvi there's a lot more to do. Most of the wires are in place on the left side of the engine, but there's nothing on the other end of any of those wires. I measured routing inside the The Mule from the firewall pass-through to the C203 and similar, then estimated the engine bay run from the firewall pass-through down to the valve cover rail and over to my first P-clamp. I just ran all the wires to that clamp and then 40" beyond, then cut them. That should be enough to finish the harness inside the cabin.
Of course I also need to dress the bundles, which I'll do with DR-25 shrink tube. Next time I'm working on the harness, I'll start a list of DR-25 sizes and lengths to order. I can probably just start off with 50' of 1/4" for all the 2-3 wire bundles there are, and work up from there to shorter lengths of larger sizes.
I'll need to work on the main harness bundles that go to the coils next time, which will require me to figure out the best & cleanest way to get the main harness across the valley, as well as breaking out the branch that goes to the C500.

I found I had two orange wires for the fuel pump going to the oil pressure sender/switch (Reference Designator: OPS/S). Thinking about this for a moment, I decided that since the fuel pump fuse is hot-at-all-times (HAAT), the feed from that fuse should be red, while the switched side of the OPS/S & fuel pump relay should be orange. I don't know why GM made the "upstream" side of that circuit orange, but they did. I did not previously have red 16ga in my wire list, so I have to order a bit now.

The GT150 female 3 cavity inline connector for the oil level switch/oil temp sender does not have ANY cavity numbers on it that I've found. Of course it does have "Delphi" printed on it. I guess those are the company priorities. No wonder they went bankrupt.

Harness to do:
Order RED-16 wire
Order RED-8 wire
Order connector seal for alternator connector
Connect RED-16 wire to OPS/S-D
Build Alternator output wire
Oil level switch/temp sensor pinout (Pick one and drive forward; if it's wrong switch later)
Compressor clutch pinout (which side is which? Correct connector?)(Pick one and drive forward; if it's wrong switch later)
ALT-I & ALT-L down from 18 to 22ga wire?
Find/Source/Order ECM connector bodies
Rework manifold harness to support C527 harness bundle routing

General build to do:
Order 2007 Impala accelerator pedal assembly
Order 2006 Corvette O2 sensors
Order 1995 Cadillac A/C compressor

Wow, those images ended up very large. How do I fix that?