Saving 71 Demon...

-

Skezix

Active Member
Joined
Jun 14, 2020
Messages
40
Reaction score
26
Location
Spokane
Well.. first off I have building gm muscle cars for almost 2 decades.. Mostly chevelles.. Daughter loves the early 70's buicks and they are ok yet for multiple reasons I wont go into I will not build one. My first car was a 73 Sport with a slant 6 that I could not kill.. Recently found this 71 Demon and it appears daughter (she is 29) really likes the car.. so.. It will be very mild build street car 340/727/8.75 that is used for cruise ins and local shows..(dad might push it a pass or two just for giggles). Starting this thread and I am sure the questions will be rolling out as we go.. I have a few questions to start off.. I am frugal but not cheap and I am not rich but do things as correct/safe as possible. I have been searching and reading forums here for sometime and have a general idea of what I want to do, although some posts are older I figured I would see current opinions/options.

Going to upgrade to power/larger bolt pattern disc brakes up front (rear end susp/diff/brakes will be next) I know there are many ways to accomplish this, attempting to go plug and play up front although open to suggestions.

K member is out going to rebuild entire front suspension and have it ready.

1. Lower control arms, new bush and go or upgrade pin/reinforce kit?
2. Figured upper control arm swap (like better geometry) I will go tubular, what brand for easy fitting swap?
3. Strut rods.. figure adjustable to help with geometry.. best fitting/easy install brand?
4. Good quality brake kit for the front? No need for wilwood and I know everything is chinesium who's chinesium kits are decent?
5. Lots of torsion bars out there.. street machine does brand matter and what brand might that be?

Pulled a pic off my phone from when I was covering her when I got her home..

Demon.jpg
 
Wow. That's a heavy project! For a mild engine build, what do you think about the 904 Torqueflight instead of the 727? It's what my 1970 318 Dart came with, and its a smaller and lighter unit that is plenty strong for the job. Truth be known though, I'm slipping a 200-4r into mine for the next buildup.
 
Going to upgrade to power/larger bolt pattern disc brakes up front (rear end susp/diff/brakes will be next) I know there are many ways to accomplish this, attempting to go plug and play up front although open to suggestions.
Dr. Diff.
Quality parts, good prices, and awesome customer service. You can't ask for better.
DoctorDiff Drivetrain Components
 
Wow. That's a heavy project! For a mild engine build, what do you think about the 904 Torqueflight instead of the 727? It's what my 1970 318 Dart came with, and its a smaller and lighter unit that is plenty strong for the job. Truth be known though, I'm slipping a 200-4r into mine for the next buildup.
It's a 340 car I should keep the drive train it came with. I was thinking of OD for as much as I know everything about GM trannies.. the 200 is good and can be built to be even better but the proper case needed to build one that will last are difficult to find and gm parts in a in a mopar.. not really my flavor. I have built some older fords that were built ford tough with chevy stuff but I just couldnt do it for a dodge..
 
I like the 74 A-body disc brake set up. 73-76? (I think). You will need the upper arms (larger Balljoint) complete spindle ,rotor caliper assembly and flex brake lines.
 
Ya, I have been in touch and been on the website. Appears to be one stop shop for vast majority of my needs although if I am going to be spending upwards of 5k with anyone I do not deal in text or emails only.
Unlike some sources, he actually answers the phone, answers questions and helps you make informed decisions.
 
Picked up a few things from the powder coat boys.. I believe I have my front suspension build figured out with as a few have mentioned DrDiff's help. Still trying to figure out of adjustable strut rods going to be that beneficial for a street cruiser. While the body is on the rotisserie I figure I will build the front and rear susp and have them ready to go.

Resized_20221111_101253.jpg


Resized_20221111_101300.jpg
 
Cool! Love to see another local on here. I am out in Davenport, but am all over Spokane all the time.

My brother lives in Spokane and is building a '71 Demon as we speak. His started blue but will be Orange in the end.

Still have the Duster too?
 
Chinkesium and brakes. Read that over and over. Then think about your daughter driving it. That is all. Good luck with the project!
 
Cool! Love to see another local on here. I am out in Davenport, but am all over Spokane all the time.

My brother lives in Spokane and is building a '71 Demon as we speak. His started blue but will be Orange in the end.

Still have the Duster too?
I do have the duster. I was going to restore it as it is a 340 car but I found this demon.. Sadly I will be using parts from the duster it was a complete car semi running.. The demon has no body tag, it appears it was a 318 car as the K member is not a 340.. and I was told it was the red but from what I can tell as I tear into her she was orange.. Not sure what color in the end I will go. Building for my adult daughter, she likes the old school colors as she was raised at car shows but I may do a candy over top or something a bit different.
 
Last edited:
Tore out the dash, going to restore it for the Demon.. Appears the dash harness is still pretty intact.. few things I have found and need to investigate. As the manual does not seem to depict demon or duster.. I am guessing barracuda or valiant wiring schem is used? Anyhow pic 1 it appears someone delivered power to pin 8 (oil) if valiant is what I am suppose to be using. Looking at the plug the wire that should go here is missing, the only thing cut near here is a violet/purple. Did not see it in the manual but was just glancing as I was tearing it down.

Steering column had an interesting fix, based again on a manual that does not depict duster/demon it appears white is brake? Anyhow again have not done much more than a quick glance at the manual to figure out what someone did here.. my concern is was this a possible solution to a problem elsewhere..

Resized_20221217_111945.jpg


Resized_20221205_140331[4643].jpg


Resized_20221217_113346[4642].jpg
 
Tore out the dash, going to restore it for the Demon.. Appears the dash harness is still pretty intact.. few things I have found and need to investigate. As the manual does not seem to depict demon or duster.. I am guessing barracuda or valiant wiring schem is used? Anyhow pic 1 it appears someone delivered power to pin 8 (oil) if valiant is what I am suppose to be using. Looking at the plug the wire that should go here is missing, the only thing cut near here is a violet/purple. Did not see it in the manual but was just glancing as I was tearing it down.

Steering column had an interesting fix, based again on a manual that does not depict duster/demon it appears white is brake? Anyhow again have not done much more than a quick glance at the manual to figure out what someone did here.. my concern is was this a possible solution to a problem elsewhere..

View attachment 1716023341

View attachment 1716023342

View attachment 1716023343

Did the Demon come with a Rallye dash? Pretty sure the wiring is different between the Rallye dash and the standard square speedo one.

I will look up the conversion @72bluNblu did on his car tomorrow. Might give some ideas why you are seeing differences.
 
Demons did come with them from my research. Not worried about the wiring as I have a complete harness for the car with the rallye dash. Not really seeing any differences, just the "Fixes".. The manuals i have do not depict demon or duster they only depict valiant and barracuda. Have both 71 dodge and plymouth body and chassis.. I found wiring schem online from a 70 valiant/duster and 71 valiant/duster. It appears the duster I have is an early one because it matches the 70 schem.

Attempting to see what these "fixes" were.. often I have found a fix in one place was a remedy for a problem else where.. Thus the "fix" on the harness in the column.. I want to know what they did so I can figure out if there was an actual problem in the wiring of the harness in the column or was this done to remedy a problem elsewhere in the system.
 
Last edited:
I had some goofiness in my car that I remedied as well. You know when you look under the dash and see wire nuts, you're in trouble.

I basically just took anything that didn't work or was modified and traced the wires out and ran continuity checks to make sure I had the correct wire on each end. A power probe is nice because it allows you to run voltage to individual wires to check things as well. Its not necessary though.

About 15 butt splices, a couple additions to the fuse box and a bunch of heat shrink later, everything is clean and working as intended with the original harness. Replaced a few wires that were toast and that's about it. Nice thing is once you dig deep into the harness like that, it makes future troubleshooting much easier since you don't have to reverse engineer it anymore.
 
Demons did come with them from my research. Not worried about the wiring as I have a complete harness for the car with the rallye dash. Not really seeing any differences, just the "Fixes".. The manuals i have do not depict demon or duster they only depict valiant and barracuda. Have both 71 dodge and plymouth body and chassis.. I found wiring schem online from a 70 valiant/duster and 71 valiant/duster. It appears the duster I have is an early one because it matches the 70 schem.

Attempting to see what these "fixes" were.. often I have found a fix in one place was a remedy for a problem else where.. Thus the "fix" on the harness in the column.. I want to know what they did so I can figure out if there was an actual problem in the wiring of the harness in the column or was this done to remedy a problem elsewhere in the system.

Wow, I dropped the ball on this. Never did get a link for you.

Sorry, should have been clearer, wasn't asking if Demons could be ordered with the Rallye dash, was curious if the one you have had it. Reason I ask is that the wiring harness won't plug in to the Rallye dash if it had the standard dash and I thought maybe that was the reason for some of the differences you were seeing. But sounds like you are figuring it out.
 
That's a 1970 rally dash cluster....for thumbwheel radio
 
-
Back
Top