Chris' Coupe Build #566 - Rear Camera. EPBs. Hatch floor.

[460.465USMC]

J&L oil separator: not electrical related and not needed for a while, but this is on my list and satisfied the free shipping minimum at Summit for a recent order. It's a plug-and-play installation. “Reduces blow-by and carbon buildup. Maximizes performance and efficiency”. At least that's the advertising. I put one on my last build as well.




A few weeks back my Braum ORUE seats arrived. I haven't done much with them yet other than to send a panicked PM to JimStone worried they're too big and won't fit. He graciously replied back, and talked me off the ledge. They come with a tilt back and sliders, but not sure how much tilt I'll be able to use, or the sliders for that matter. I'm looking forward to installing these.

[Papa]

Great progress, Chris! I like what you did with the wiper motor. Way yo think outside the box and really takes advantage of the flexibility the kit provides.

Dave

[PNWTim]

Looking good Chris. I know the program of "wiring a little bit every day". It's a little bit along the same lines as eating an elephant.

[460.465USMC]

Great progress, Chris! I like what you did with the wiper motor. Way yo think outside the box and really takes advantage of the flexibility the kit provides.

Dave

Thanks, Dave. It was looking like I would have to relocate some of those items on top of the right FB to make room for the motor and clearance for the cable tubing. Wasn't excited about that prospect. I think this will work.

[460.465USMC]

Looking good Chris. I know the program of "wiring a little bit every day". It's a little bit along the same lines as eating an elephant.

Well said, sir. Even though I enjoy the wiring part of the build, by the time I'm done I'll be looking forward to something, anything else but wiring for a while.

[Namrups]

Not sure if I'm looking at the picture right but it looks like your wiper moter assembly is facing the wrong way.

[460.465USMC]

Hi Scott. With it mounted above the driver's side footbox I'll admit it looks different. It's rotated 180 deg. from where it would be if mounted above the PS footbox. From the angle of the picture it's not visible, but the cable assembly exits toward the center of the windshield. The initial orientation of the drive wheel inside the assembly will be different as well, but they assured me it will work. I hope they're right.

Are you getting close to driving season over there? There's snow in my yard over here, but supposed to be close to 70 deg. in a few days. That's March in the Pacific Northwest.

[Namrups]

Hi Scott. With it mounted above the driver's side footbox I'll admit it looks different. It's rotated 180 deg. from where it would be if mounted above the PS footbox. From the angle of the picture it's not visible, but the cable assembly exits toward the center of the windshield. The initial orientation of the drive wheel inside the assembly will be different as well, but they assured me it will work. I hope they're right.

Are you getting close to driving season over there? There's snow in my yard over here, but supposed to be close to 70 deg. in a few days. That's March in the Pacific Northwest.

I had my first drive of the season last week when the temp hit the upper 60's! Drove to get bloodwork done. It has snowed again since then so she waits for drive 2!

[460.465USMC]

Electrical work continues. Making some progress. Just wrapped up the front harness install. Nothing much off script other than lots of soldering as I relocated and extended wires to match the route I chose. I also ran a couple extra wires: (1) daytime running lights, and (2) fog lights. I wrapped the RF split loom with cloth adhesive, as the split loom is a bit unsightly IMHO.

This is where the front harness connectors seemed to naturally fit. This location is also quite agreeable with the connectors coming from the RF fuse panel. Added a cushioned clamp to keep it in place. Not the greatest picture, but the yellow arrow points to the front harness connectors, which stop just shy of the forward edge of the 1.5" chassis cross tube.




The harness exits the front of the FB and travels along the outer edge of the 1.5" diagonal. I opted to route the PS harness across to the right side through the 1.5" tube. From this "Y" the left side simply travels down the 1" nose support tube. The clecos will remain as long as possible, as I'm not in a hurry to seal up the outside panel of the driver's side footbox.




The horn wires split out just in front of the "Y" (yellow arrow) and sneak underneath to the Bad Boy horn. I'm adding grounds at all four corners--preemptive strike against grounding Gremlins! The fan ground wire (#10) is seen here (lower arrow). It will terminate in a Weatherpak where it will join the +12V (from the Coyote PDB) at the lower radiator hose exit. The rest of the left side harness grounds will connect here as well.




Horn wires connect to the horn above the steering shaft.




Here you can see where the positive lead for the fan exits the main battery lead bundle on the lower chassis tube. It routes to the same radiator tunnel opening to meet up with the ground wire noted above.




Lastly, the right side of the front harness exits the chassis tube and follows the nose supports. Also visible is the chassis ground where all of the right side ground connections with tie together.




On to the rear harness. Really looking forward to getting the gas tank reinstalled, and the hatch floor panels in place permanently.

[PNWTim]

Great progress Chris! It's a good feeling to finally work out routing of major harnesses. I originally was going to go through the cross tube like you did but for some reason changed my mind but I can't remember why. Either way, keep up the good work.

[460.465USMC]

Thanks, Tim. Agreed, I'm actually starting to feel some momentum. Feels good.

I thought about going across the top of the chassis tube instead of inside. Hopefully, I didn't miss something I should have accounted for by using this route. I've seen it done both ways on builds. One obvious downside is future access to that part of the harness, but hopefully that won't ever be required.

[460.465USMC]

The rear harness is the last of the major harnesses I need to install. There are a number of circuit additions. I mocked it up in order to break out these circuits to where they need to land (ordered front to rear):

• Reverse light switch: this one is toward the front of the T-56, on the right side. My transmission kit included the two-position Weatherpak pigtail which mates to the switch output inside the trans. This circuit runs forward to a relay (yet to be placed), whose output will run rearward through the harness via a wire pair I added. All the way back to the reverse lights, one on each side near the taillights.
• Vehicle Speed Sensor: I’m using the two-position VSS connector included in the RF harness (green, gray wires) to feed a reverse lockout module.
• Reverse lockout: this circuit is fed from the above mentioned lockout module. It travels from there into the harness, and eventually breaks out at the left rear of the T-56. There it connects to a solenoid mounted on the trans. The pigtail for this connector was also included in my T-56 kit.
• Third brake light: spliced into the left brake light wire (purple), and broke it out in the middle, where the third brake light will be mounted to the spoiler.

I'm not exactly blazing new trails here by running the harness through the forward side panel of the trans tunnel. It enters just below the brake line.




From there is makes the curve rearward, along the right side of the tunnel.




Continues rearward tucked in tightly in the upper right. The blue tape pieces mark where the breakouts need to go. Since I didn't install the drivetrain for mock-up, I measured from the motor mount stud to each connector on the T-56. Then, transferred that measurement to the tunnel and marked with tape.




The final bend, upward and to the rear. It attaches to the underside of the hatch floor tubes with more cushion clamps. The smaller loom is the Wilwood EPB harness.




Top view of rear harness. Wilwood EPB routing: from the final Y in the harness I took the circuitous route to the e-brake caliper motors. For whatever reason at the time, I didn’t want to trim and resplice.




From the pictures I took before initially removing the body, there appears to be plenty of room to secure the end of the harness legs in this area. Like the front, I added chassis grounds on the left and right sides, where all the rear circuits will tie their grounds together.




For an innocent looking harness, there was quite a bit of rework because of the accoutrements I added. It feels good to have it all in place. I’m looking forward to testing each one individually once these circuits are ready to be energized.

Side note: to help me select the correct grip range for each rivet, I measured the wall thickness of the various tube sizes.

• 1.5” tube: wall is 0.095” thick
• 1.0” tube: wall is 0.075” thick
• 0.75” tube: wall is 0.040” thick

I’m excited to permanently mount my DIY trunk box, hatch floor, and ThermoTec insulation.

Happy Building!

[PNWTim]

Looking good Chris. I am kind of regretting not running a reverse light circuit to the rear but I didn't plan on reverse lights because I thought it came with them. I am curious which lights you are using? I can still piggy back a wire back there if I had to and my Bowler reverse lockout module is designed to activate the circuit if needed.

[460.465USMC]

Hi Tim. I bought these six LED round lights from Watson Streetworks: https://watsons-streetworks.com/prod...s%2FClear+Lens. They are just over 1.75" in diameter. I can't speak to how effective they'll be, but I like their products.

[460.465USMC]

It's hard to believe the two year anniversary of my kit delivery date is this Wednesday! Just for grins, I compared my Coupe build timeline to my MK4 timeline. At the 22 month mark on the MK4, I had just completed First Go-Kart. This time around, I’m a ways away from dropping in the drivetrain.

Besides taking a couple months off from the build here and there, the main reasons my Coupe progress differs so dramatically is (1) all of the custom panels and brackets I’ve made on this build. And, (2) there are quite a few additions to the electrical portion of the build (e.g. rear camera, cruise control, back-up lights, etc.). I guess it all adds up over time.

Not to worry because my main goal is to enjoy the build process. So, if I want to take on the challenge of making my own trunk box (I did!) I’m going to do it. (Modeled after Edwardb’s, of course). There’s a lot of fun, and a feeling of accomplishment I get from going off script. And, occasional frustration. That’s what it’s all about for me. Okay, enough rambling. Back to minor updates on my progress.

Rear camera/mirror (Auto Vox T9): I changed my mind again –for the 3rd time– and decided I will mount the rear facing camera to the hatch glass, just behind/below the rollbar. I routed the rear camera cable along the top of the roll bar. Routing it inside the tubes is trick–-did that for the other part of this harness. But after a chat with PNWTim, he pointed out the cable on top of the rollbar won’t be visible with the body on unless you’re really looking for it. Summary: out of sight? Check. More serviceable? Check. Considerable time saved. Double check. In hindsight, I would do the same for the cable to the mirror. The camera comes with a looooong piece of cable, and no good way to trim it. So, I ran out the excess inside the loom. I used cushion clamps anchored by 10-32 button heads.




Wilwood EPBs: now that all the harnesses are routed into the cockpit from the fixed objects they power, I made some of my first connections in the cockpit. The Wilwood EPB harness was up first. I trimmed 4-5 feet off the 12 AWG power wires that feed the calipers. Then trimmed 6+ feet off the smaller 20 AWG wires that connect to the dash mounted control switch. All splices are soldered. More on that in a minute.

Now to the fun part: this gave me a really good excuse to test my main wiring from the battery, through the master cutoff switch, and to the +12V busbar where the EPB’s main power lead connects. This is the first time I energized the main power system. A test lead connection to ignition power, but everything else was real-world. The EPBs worked as advertised. No smoke released. Phew! The indicator light stays on with ignition power when the EPBs are engaged. Removed ignition power, and the EPBs stayed engaged. Just like they should when I’m parked and walk away. Good.

I was on a roll, so I completed the final IRS CV axle nut torque (98 lb ft + 45 deg). The brake rotors didn’t budge whatsoever with the EPBs engaged. Nice! (Tried this months ago with my daughter’s foot on the brake pedal, but the rotors still spun). Put a witness mark on the axle nut, and put the wheels back on.

Papa recently gave a nice demo video of his Wilwood EPBs, so I won't duplicate here. With the EPB circuits completed, I felt confident to silicone and rivet my forward transmission tunnel panel. Not much to look at, but the rats nest in this area is about to become even more rats-nestier as I add in the harnesses for cruise, lockout solenoid, etc.




Hatch floor: With the EPBs installed and tested, there was no good reason not to button up the hatch floor. So, I put the final torque to the -6AN connections at the Trickflow fuel filter and at the pump. Installed the forward hatch panel, followed by the larger rear panel and trunk box hinges. Then, applied Thermotec, but left the outer edges unattached so I can slide in the hatch slides. Speaking of those, my final powder coat batch (hopefully!) should be ready for pickup any day.

Took this shot just before laying down the Thermotec. You can see the missing rivets along the left and right edges.




Power Steering cooler: it wasn’t in my mind to install one, but ultimately decided the benefits are there for the extra heat protection IF I autocross. Not to mention it gives me a good excuse to upgrade the hoses. In both builds, I’ve used Teflon lined SS braided hoses and connectors from Breeze for my fuel lines. Will do the same here for my power steering hoses. I’m always happy with Breeze parts. Mark is a pleasure to work with. Good quality.

I really liked where Edwardb mounted his cooler. But, I don't have clearance to do the same. So, this is the location I found. Not as clean, but it should work. I'll install a 120 deg. connector for the connection back to the rack, and a 45 deg. on the other outlet to the pump. The rest will be 90 deg, and all are -6AN.




Electrical misc.: like others I spend a lot of time trimming down circuits/harnesses that are way too long for my application. And, in some cases, extending them. For those circuits where I’m not using connectors (e.g. Weatherpaks), I solder wire-to-wire. Those connections are solid, but perhaps a little bulky, and not the most professional looking, especially the large gauge wires. So, I’m going to try these non-insulated butt connectors. The non-insulated butt splice is no different than the uninsulated wire-to-wire soldered sections. Both require shrink tube. I think this may even improve the reliability, and give a more professional looking end result. Because, you know how many eyes will see these connections inside the wire looms, or tucked under the chassis. Know anyone who’s three inches tall?





Mini ATM fuse pigtails: For those connections which need a fused input (constant or switched power), I’m going to try these Mini ATM pigtails. Available from Del City in 12 AWG (up to 30A), or 16 AWG (up to 20A). I ordered a few of each. Also, with the additional electrical circuits I’ve noted, I think a dedicated ignition busbar is unavoidable. A place is needed to gather switched power. Not to mention it will also provide an easier way to isolate a circuit if future troubleshooting is needed.

[Papa]

Nice work, Chris. You'll like the uninsulated butt connectors. I used them quite a bit this build.

Dave

[460.465USMC]

Thanks for the confirmation, Dave. I was wondering if other builders used these. Not sure why it took me SO MANY connections before giving these a try. I was thinking to apply a little solder after the crimp. Do you as well, or is that completely unnecessary?

[Papa]

Thanks for the confirmation, Dave. I was wondering if other builders used these. Not sure why it took me SO MANY connections for me to give these a try. I was thinking to apply a little solder after the crimp. Do you as well, or is that completely unnecessary?

No solder for me, just crimp and shrink.

[ToeKneeNose]

The uninsulated butt connectors are great for connecting single wires or even a few smaller wires together in a smaller space. If you want to step up another level, look into open barrel connectors. They serve a slightly different purpose and require a little more hand coordination, but it is a single crimp. You can add several different sized wires and change the direction each wire is facing. It's really good to run a longer large single conductor and then branch off to smaller conductors in the harness or near the end of the run.

https://www.prowireusa.com/p-3226-op...ose-piece.html
openbarrel.png

[460.465USMC]

Interesting. In my limited wire-crimping travels over the years I don't recall running across these splices. I can see the slightly different function they provide. It looks like they require a special crimper. Which crimper have you found effective?

[PNWTim]

Thanks for the confirmation, Dave. I was wondering if other builders used these. Not sure why it took me SO MANY connections before giving these a try. I was thinking to apply a little solder after the crimp. Do you as well, or is that completely unnecessary?

I just ordered another hundred butt connectors. Shockingly, I used up the first hundred since I ordered them in November of 2024. I believe my main harness took about 40 of them so I guess I shouldn't be surprised. I don't think you mentioned it but one key to using these (other than not forgetting to slide the heatshrink on prior to the second crimp) is to use a good crimping tool. I have two of these (not sure why) and although I have other crimpers that will work, these are my go to:

https://shop.channellock.com/product...ye_uHszm3VYnhk

I enjoy their simplicty for both insulated and non-insulated connectors and they provide great leverage. You can crimp up to about 10 gauge fairly easily.

I also never use solder except in very limited circumstances. I think it's pretty well defined by OEM's that a good crimp and connector is superior, doesn't crack or corrode over time and allows replaceability.

[ToeKneeNose]

Interesting. In my limited wire-crimping travels over the years I don't recall running across these splices. I can see the slightly different function they provide. It looks like they require a special crimper. Which crimper have you found effective?

crimper.png
https://www.prowireusa.com/p-3900-me...rimp-tool.html

I don't remember the exact model I have but It's probably just like the one listed on that site. They do a pretty good job of having the associated crimper needed.

I bought a lot of tools for my last project so I get to reuse them when I start wiring my coupe.

[460.465USMC]

I just ordered another hundred butt connectors. Shockingly, I used up the first hundred since I ordered them in November of 2024. I believe my main harness took about 40 of them so I guess I shouldn't be surprised. I don't think you mentioned it but one key to using these (other than not forgetting to slide the heatshrink on prior to the second crimp) is to use a good crimping tool. I have two of these (not sure why) and although I have other crimpers that will work, these are my go to:

https://shop.channellock.com/product...ye_uHszm3VYnhk

I enjoy their simplicty for both insulated and non-insulated connectors and they provide great leverage. You can crimp up to about 10 gauge fairly easily.

I also never use solder except in very limited circumstances. I think it's pretty well defined by OEM's that a good crimp and connector is superior, doesn't crack or corrode over time and allows replaceability.

Thanks for the confirmation, Tim. This feels like a Homer Simpson moment (D'Oh!). Really appreciate the feedback.

Crimper: I have the Klein version of that crimper. I bought it in the late 90s. I was a field technician in the two-way radio business after the Marines (avionics). One solid hand tool. It has a 10-12 AWG slot and a second slot for 14-22 AWG. Plenty of reliable crimps over the years. It doesn't owe me anything.

This is really good news. Not only will my splices be less bulky, but I'll save a ton of time by crimping v. soldering. Glad I found these right before my deep dive into the cockpit spaghetti factory.

[Skuzzy]

When using crimped connectors, on stranded copper wire, I usually, tin the copper first. This holds the wire together better and makes for a more solid crimp.

Added: When I have to do a lot of crimps, I light up the solder pot and use the MAPP torch to heat the copper and dip it in the solder pot. I can tin 20 to 30 wires in a few minutes that way.

[460.465USMC]

Appreciate the tips! I'm getting exciting to do some splicing.

[jemorgan3]

I have not run a single wire on the coupe yet, but in other projects I’ve used the but connectors that have the solder and flux inside the sleeve, and the sleeve is shrink wrap.. any opinions on using this technique vs a physical crimp?

[460.465USMC]

I used something like that from Molex for the submerged splices on my in-tank fuel pump on this build. As I recall, they were pricey. Not bad if you only have a few to do. But, depending upon how often you detour outside the "standard" F5 build (i.e. are you adding electrical circuits?), and how much you rework (or don't) the harnesses for your application, I think the cost and time to install would be a significant factor. I don't have data comparing the two from a reliability standpoint, but perhaps a more knowledgeable builder can weigh-in.