1973 Plymouth Duster repair and rebuild

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Hopefully I dont need to start a new thread for this question.

Lets assume I am going to weld the shock hoop on the chassis.

Here is what I see I need to do...
  • Remove the shock hoop from car
  • Pull the HDK 1/2 in sleeves
  • Clean welding surfaces with flap wheel
  • Weld/fill the 9/16 hole on the outside wall of chassis
  • Weld/fill the 3/8 hole on the inside wall of chassis
  • Spray Weld-Thru primer on chassis
  • Clamp the hoop in the correct location
  • Weld
  • Paint
The issue that caused this problem is I had to over drill the outside chassis holes to 9/16 to allow some wiggle room for the bolts to go thru the crush sleeves and chassis.

My question/concern, what about the exposed weld on the inside of the chassis. Isnt that going to rust? How to I protect against that if I dont have access to it?
 
JohnFM3 said:
Ok, I am not sure I showed my solution for the ignition power. Based on the suggestions here, I went with two 4 terminal relay approach. Then used the blue and the brown wire from the wires that goto the resistor. Blue has 12v during run, Brown has 12v during start. The blue and brown wires are only used for triggers and pass thru the relay to ground. The relays get a 12v which will come from a breaker protected power distribution block (such as the one from MSD) straight from battery. There is the possibility of replaying the relays completely with the msd power distribution block. More on that later.

So in further investigations after finding the below charging circuit diagram, both the blue and the brown wire come directly from the ignition switch. In the event of the blue wire, it also goes to a field post on the alt as well as a post on the voltage regulator. As the 12v source is coming from the ignition switch, I am going to assume that its safe to use in the method I am, unless someone here believes I am making a mistake.

Meanwhile, I am digging into the harness and cleaning things up. Mainly sorting out why wires were cut and correcting them or notating. The orange wire off the harness connector that goes to the ignition switch was cut on the switch side. Come to find out that it was no longer needed as there wasnt a automatic shift indicator which needed lighting. I will definitely keep that in mind so if I install a gauge (such as a wideband air/fuel) one from autometer, I now have a power wire for lighting.


View attachment 1716476731


View attachment 1716476735
Click to expand...
Damn. Just DAMN
 
mygasser said:
get some cavity wax and the long nozzle, you can coat the inside of all the inaccessible areas then.
neil.
Click to expand...
Ok, I am looking at Cavity Wax. KBS seems to be highly liked, as well as 3M. It appears that the 3M has a better wand for a more complete coat. Do you have any brand recommendations?
 
RustyRatRod said:
Damn. Just DAMN
Click to expand...
Oh but wait, there's more.

So does everyone remember when I spoke of a factory harness wire going from the coil, to the harness plug on the passenger side of the engine, and then a bypass wire going from that to the side of the bulkhead connector and under the dash.....

There was a yellow wire in there that I "ASSUMED" the wire from the coil went to. For those who have experience in this, you will know that most likely that Yellow 16 gauge wire is coming from the light switch and going thru the bulkhead connector to the front marker and park/turn lights. If the prior owner was using that wire for ignition, no wander it was not starting up.... lol I also found a wire on the engine bay side of the bulkhead connector which came from the harness, a black one stripped and ready for termination. I found that wire was the marker light side of the front lighting circuit, so I soldered a red wire to the yellow wire inside and the black wire outside. I also had to repair a break in the front left side marker light wires. Nothing big, cut the bad section out of the hot side and solder to broken ground side back together. Guess what, I now have working front and rear marker lights, tail lights, and front park lights.

Yeah, thats right. I started working on getting the front lights to work again and found that gem of a situation.

Next in my items to dig into, the reverse lights as well as the turn indicator light circuit. I have also bought 10 instrument cluster light bulbs, that will be last. With the new light switch, high/low beam dimmer switch, and the turn signal relay, everything should work as long as the wires are good.
 
I was commenting on your electrical repair. ...all of this is CONSTRUCTIVE so please take it in the way it is meant. How long do you think those CHEAPASS parts store total chinkesium colored connectors will last before corrosion starts? Or GOD FORBID something "foreign" and metallic just "happens" to fall in there? It happens. I'm always taken aback that guys think those are even CLOSE to a proper electrical repair. They're not. And LORD KNOWS, this is coming from a guy that LOVES CHEAP and LOVES a shortcut. You could have and still easily could do these.

cart.electricscooterparts.com

Bosch Type Relay Wiring Connector with Harness

Bosch Type Relay Wiring Connector with Harness
cart.electricscooterparts.com cart.electricscooterparts.com

I highly recommend them. ...and DON'T use butt connectors to make the connections. LOL I'm not trying to rag on what you've done, I'm merely trying to point out a better way.
 
RustyRatRod said:
I was commenting on your electrical repair. ...all of this is CONSTRUCTIVE so please take it in the way it is meant. How long do you think those CHEAPASS parts store total chinkesium colored connectors will last before corrosion starts? Or GOD FORBID something "foreign" and metallic just "happens" to fall in there? It happens. I'm always taken aback that guys think those are even CLOSE to a proper electrical repair. They're not. And LORD KNOWS, this is coming from a guy that LOVES CHEAP and LOVES a shortcut. You could have and still easily could do these.

[/URL][/URL]

I highly recommend them. ...and DON'T use butt connectors to make the connections. LOL I'm not trying to rag on what you've done, I'm merely trying to point out a better way.
Click to expand...
I was not taking offense to anything you said. I am happy to see you interested in my journey...
:)

That setup will only be there until I get a job. Afterwards, I am buying a MSD power distribution block with ground/hot triggers. Then I will run both trigger wires to that, and run that to the coil.

In the long run, once the Barracuda is on the road, I will be installing a 18 circuit Painless wiring harness with bulkhead connector.
 
JohnFM3 said:
I was not taking offense to anything you said. I am happy to see you interested in my journey...
:)

That setup will only be there until I get a job. Afterwards, I am buying a MSD power distribution block with ground/hot triggers. Then I will run both trigger wires to that, and run that to the coil.

In the long run, once the Barracuda is on the road, I will be installing a 18 circuit Painless wiring harness with bulkhead connector.
Click to expand...
Now that plan I can endorse.....not that it matters if I endorse anything. lol
 
Well, with a short conversation with Denny from HDK and the unplanned death of my mini-lathe, welding the shock hoops on is the plan. Thanks to MyGasser for the suggestion of Cavity Wax. Will keep everyone updated as it comes.
 
Regarding the welding and repairing of the drilled holes, I am considering welding the 1/2 and 9/16 holes closed. Then grinding them flat. My other thought is use my hole cutter to cut little doughnut pieces of metal which will fit the hole, then weld around. And again still grind flat. Thoughts?

Keep in mind, I am a unemployed Server System Engineer, not metal fab. I do have a good mig welder with gas that runs on 220v at 40amp, and it makes me look pretty good. But I am only guessing on what power and wire feed settings I should use based on research from the internet and the supplied owners manual.

I am considering putting 2 tack welds on each arm of the hoop, then pay a professional mobile welder to complete the job. Even still, I have holes in the chassis I need to deal with. Seeking suggestions.
 
re welding holes in sheetmetal, grab a thick flat piece of copper and hold it on the backside of the holes while welding them. the weld won't stick to the copper and you get a fletter backside to the weld so less grinding.
neil.
 
mygasser said:
re welding holes in sheetmetal, grab a thick flat piece of copper and hold it on the backside of the holes while welding them. the weld won't stick to the copper and you get a fletter backside to the weld so less grinding.
neil.
Click to expand...
Thanks for the advice, sadly I got this advice after I completed the work.

So the car now has the shock hoops welded in. I started my weld on the face of the metal and rolled it into the back so that I had enough thickness grind. If any holes showed on the first grind, weld again and fill any additional holes result to welding. Grind again, and good to go. Took a portion of the chassis to metal, sprayed with weld thru primer, located the shock hoops and welded. I will be painting front end parts and installing the remaining kit over this weekend. Painting is going slowly due to colder weather resulting in a colder garage. That color you see around the weld is the copper weld thru primer. I will be painting primer and paint tomorrow. Should be ok for tonight.

20251120_172434.jpg



Since I have more drilling to do in the chassis, a quick drilling jig was created using one of the provided crush sleeves no longer needed for the shock hoop. I wish this would have came with the kit.
20251120_173006.jpg
 
Once on the road and I am employed, the engine will be refreshed with re hone of cylinders and current size rings, mains and rod bearings. Finished off with a 264 cam with 440 lift

Hopefully sooner than later. As that means I am employed.
 
JohnFM3 said:
Once on the road and I am employed, the engine will be refreshed with re hone of cylinders and current size rings, mains and rod bearings. Finished off with a 264 cam with 440 lift

Hopefully sooner than later. As that means I am employed.
Click to expand...
Just don't get a Comp cam.
 
New blue dot solution in place. The blue LED's I bought which I was going to glue behind the glass blue dots, they have replaced the glass blue dots. I used the blue dot metal holder to install the LED in, then installed like normal. Only now, I can tie the LED to just the brake circuit if I wish. Or maybe a switch to just stay on. Dont know for sure.

20251121_183800.jpg


20251121_183809.jpg
 

@RustyRatRod I recall you providing quite abit of info on Axle geometry on a thread I was reading up on, hopefully you can provide some insight.

Everyone who has a thought, please chime in.

I am under the assumption that I am using the pinion angle numbers found in relation to the perches being the 0 degree reference when installed. If I am wrong there, lets start with that. I have read people comparing it to the transmission output. And maybe that number is different than the relation between perches and pinion. I just want the axle perches set to OEM a-body to get started with.

As you can assume, I am now at the point of trying to weld in my perches on the ford 8.8. I am also trying to use CoPilot to see what errors I find, filing bug reports when I see them. CoPilot and my research following shows a pinion degree of 5 degrees down. I am assuming this is to compensate for large power and axle wrap pulling the pinion up. At one point in my searching, I found a factory setting of ~1 to 2 down. Though I can not find it again.

My neighbor came over and looked at the setup of the 7.25 out of my 1969 barracuda (318 w/904). It showed 8 degrees pinion Up.

What the hell? A difference of 13 degrees is a huge margin of error. I am taking the assumption that I dont have enough power to worry about custom geometry due to axle wrap or setting up weird suspension configurations. I want to set the 8.8 to a-body OEM.

Now take into consideration that there is a axle center line change as the 8.8 is a larger axles shifting center line up from the leaf springs, add the mopar perches I bought, and we could be close to 1 in up resulting in the rear of car sitting 1 inch lower. Not sure how I will counter that. May use a 1 degree shim depending on the change of having 1" longer shackles in the rear to set ride height where I want it.

The pisser is, my neighbor was so sure of the 8 degree's that we burned the perches in. But my continued research is showing else wise. Where am I going wrong if my barracuda axle is correct?
 
Stock Mopar perches are generally welded on so that the pinion center line points ~5 degrees DOWN from level. Get it there and it should be about right.
 

RustyRatRod said:
Stock Mopar perches are generally welded on so that the pinion center line points ~5 degrees DOWN from level. Get it there and it should be about right.
Click to expand...
I have been in debate over this topic with my neighbor who knows way too much doing his own fabrication. Do you have any good references I can point him to supporting your advice and what I found? I wanted 5 degrees down from level. He provided a compelling argument for why 8 degrees up.
 
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