1974 Challenger Restomod

[Dmod1974]

I painted all of the plastic pieces with a spray gun and SEM Landau black.  Overall, I think it came out pretty nice.  It doesn't look like it was painted at all.  Cleaning off old rattle can paint from some of the parts I previously "restored" when I was younger was without a doubt the biggest PITA of the whole process.



The sun visors came out great too.  The crimped on end pieces were badly pitted after rust removal, so I spray painted them with chrome paint after sanding.  Eastwood Silver Cad paint ended up being a perfect match for the pivots.

[Dmod1974]

The dash light bar was pretty straightforward.  Again, removing the old paint was the hardest part.  After stripping I hand painted the reflector housings with White Testor's paint and matte cleared them.  I pop riveted them in; I can't justify a tubular rivet gun on a restomod build like this.

[Dmod1974]

Driver's side fresh air vent next.  Separating the rubber seal from the metal door was NOT easy.  It was rusted pretty bad, but under the rubber seal it had some kind of anodized or gold plating so I ran with that.  Stainless steel paint, Eastwood Gold Cad, and then matte clear.  Matte clear was used over the "bar" part of the pivot and the stop bracket.  If it's wrong, oh well.  I won't see it and it looks a heck of a lot better than it did before.  The entire thing was rusted and rattle canned over the rust.  I used a bunch of clamps and 3M super glue to attach the seal to the metal flap again.













I'm going to paint the new door and quarter interior panels in Landau black as well so it all matches, and I'm restoring the door cups and door inserts.  I'm also sourcing factory A/C vents.  I figure if I'm going to order a new dash, this is the time to make that switch and ditch the Vintage Air under dash vent bar.  So far, I have a RH vent.  The search continues for a good center vent assembly.

[YellowThumper]

Plenty of good "busy" work there.
Curious if you have your interior headliner yet.
Mine is horrible and will be replacing soon.
Been awhile but have looked and could never find one that looks the same.
As mine is also a 74 I have wondered if it is different from other years.

[Dmod1974]

I received my new steel core dash from ABC a week or so back.  I opted to go with an A/C dash pad this time around to get away from the underhung Vintage Air vent bar.  Factory vents were $$$$, as were the side speaker grilles.  I also rebuilt all of my switches and painted all of my rallye gauge parts.

Overall, it's a nice piece.  MUCH better than the old ABS POS that I bought 15+ years ago.  I had to do some minor trimming to get the vents to fit, and the holes for the center speaker grille were shifted forward about 1/8" or so (core shift during refoaming?).  Not a big deal since I simply drilled new holes.  My plastic speaker grille is warped (shocker), so I'll be heating that and trying to straighten it before buying a new one.  I'm not setting the VIN plate in until I get the dash pad mounted on the dash frame that I'm still waiting to get back from powdercoating.  I want to be 100% sure it is ok before setting those $50 rivets!

[Dmod1974]

I think I previously showed my dual 3.5" speaker plate for the center grille.  I painted it and installed it along with fabbing some tweeter brackets to mount speakers under the side speaker grilles.  These are paired with 6.5" components that will be mounted in the kick panels.




Conceals pretty well after paint!




Crude, but effective brackets.






Blends in pretty well, especially once it's in the car!



And finally, the rebuilt switches.  These are super easy to do so I wouldn't hesitate DIYer's trying.  My defog switch didn't have continuity on high, but it was easily fixed after disassembling and cleaning off this weird goo or hardened grease that got onto the contact, and then reassembling.  I plan on using this to toggle a Kill Chiller, line lock, or something similar.  I can toggle two functions one at a time with this switch so I'm still mulling over what I want to use it for.



I'll be assembling the rallye bezel and faceplates this week hopefully.  Anybody aware of any how to's with pics for this?  It's such a funky setup with the backing plates and I don't want to mess it up or not have them line up when installed.

Also, for those using the Dakota Digital gauges, how to the indicator lenses attach?  Are you guys just gluing them to the black plastic bezel?  It doesn't look like it uses the light tubes?

[YellowThumper]

Looks great with all you are finishing.
Sorry no help on the Dakota question.

[usraptor]

Wow, your dash conversion came out great.  I know what you mean about the Vin plate $50 rivets.  I ended up doing my twice.    Those speakers should sound really nice and you'd never know they were in there looking at the dash. Nice job!      I just put new factory reproductions in mine.  They're adequate since I don't listen to the factory AM 8-track that often anyway.  What sound system are you going to run?

[Dmod1974]

Wow, your dash conversion came out great.  I know what you mean about the Vin plate $50 rivets.  I ended up doing my twice.    Those speakers should sound really nice and you'd never know they were in there looking at the dash. Nice job!      I just put new factory reproductions in mine.  They're adequate since I don't listen to the factory AM 8-track that often anyway.  What sound system are you going to run?

I have a 100x4 Rockford Fosgate 4 channel amp.  The kick panel speakers are 6.5" Polk DB6502 components, center speaker "mid" range speakers are JL Audio 3.5" coax C2-350X units, and rears are Infinity Kappa 6x9's.  Not sure if I'm going to stick with my Alpine head unit or custom mount a tablet or something with Android Auto in a center console extension to the dash.

[Dmod1974]

I'm still trying to find a body shop to finish my shell that won't charge me 2x what it should cost or isn't booked a year or more out, so I decided to mock up all of my wiring harnesses and engine controls while it's still in primer.  Better than risking scratching/scuffing fresh paint I suppose...

I fabbed up some door harnesses for the power lock and front windows.  I couldn't find original door jamb grommets, but I was able to find close enough substitutes.  I'm using braided nylon loom for all of the interior harnesses.  It's much lighter, slimmer, quieter, and flexible than traditional convolute tubing, and looks a lot better too.  I accidentally bought the non-split variety which requires a lot more thought and planning since you can't install it for the most part on terminated ends, but it looks a lot better IMO.









I'm using factory window switches instead of GM crap, and finding connectors to splice into my harness was a real bear.  To that end, I build a power window relay sub harness to take all of the load off of the switches/connectors, and deliver better motor performance.



I ran a 10 gauge, 1 pin connector from the power window circuit of my American Autowire dash harness to feed the low current switches, and high current relays.



A 6 pin Metripack 280 splice pack then sends power to each corner.  I lead feeds it, and a buss bar under the connector cap connects all of the others in a clean package that will be tucked behind the kick panel.  I matched the factory circuit colors to make it easier to diagnose later on.



Rear corner examples since the fronts are hidden behind the dash:





Rear body harness:  I try to blend modern tech with stockish routing where possible.









I'll be running front and rear cameras; the last thing I need after I'm done is to back into something or scrape my lower valance on a parking block!  The rear will be bolted with the license plate and will blend in with a black frame.



The front is a threaded mount model with the wires passing through a hollow stud.  Coincidentally, I was able to mount this dead center under the front bumper in an existing hole!

[Dmod1974]

I installed a remote battery disconnect now to avoid getting bounced off the track later on.  I'll keep the switch permanently mounted since it'll be easy to throw when I'm storing the car, and for track days I modified a spare reverse light housing for the handle to pass through and will pop that in along with the handle rod when needed.

[Dmod1974]

For the underhood wiring, I used a product called Z-Coil on Amazon.  It's more of a synthetic woven "cloth" like split braided loom that looks more classic car appropriate, and I think it'll hold up better than the lighter loom used in the interior.

I made 2 Bussman RTMR fuse/relay blocks for the headlights, fan control, and all of the other battery and ignition powered devices not directly controlled by the Mopar Performance PDC.  These are sealed and used Metripack 280 terminals, mini fuses, and micro relays.  Cool stuff, and easily accessible with the battery tray removed.







ECM, FPDM relay, and the American Autowire fuse holders mounted:



Mopar Performance PDC and fan solenoids mounted up.  Yes, I run continuous duty solenoids for my Lincoln MK4 fan since most relays can't handle the current this thing draws.  These are rated for continuous 100A duty.



FPDM - Fuel Pump Driver Module.  This part is only used in the Hellcrate setup for some reason.  It controls the fuel pump with PWM so no return line or external regulator is needed.  I wasn't done routing the output wiring in this pic.  I had to extend the leads and shield wire to reach the fuel tank.

[anlauto]

Did you buy a power window kit ? If so, which one and did it come with everything you needed ( other than the original switches)

[Dmod1974]

Now the fun stuff; plumbing up the supercharger cooling system!  I bought the recommended 2017 Challenger supercharger surge tank and fabbed a bracket for it.  I then used two 3/4" Dorman tees to plumb into the surge tank.  The main line is 3/4" hose, but the surge tank hoses are only 1/2".  Luckily the Dorman tees can accept 5/8" or 3/4" by trimming the ends.  I spent a lot of time in Gates' molded hose catalog to find 5/8" to 1/2" transition hoses that would work here. 

Here's a parts list to save others some time:
- (2) Dorman 84757 heater tee's
- (2) Gates 18486 hoses

Cut and trim as needed to fit.  I used heat shrink band clamps since they're cleaner looking and I don't want a million clamps to worry about coming loose.





The LTR outlet hose is just bulk 3/4" hose, luckily.



For the supercharger coolant pump inlet and outlet, I used two Gates 12018 molded hoses and one Dorman 3/4" hose connector. One end of the hose is 1", and the other is 3/4".  The Hellcrate manual says to use 1" hose for numerous components, but that's not entirely correct.  Only the SC pump fittings are 1", and the factory Hellcats transition to 3/4" immediately before and after the pump which is used everywhere else (LTR's, SC heat exchangers, etc.)

The pump inlet mates up perfectly with the tee and tucks in nice and tight under the battery tray ledge so tire rub is a non issue.  The outlet fits under the headlight bucket and over the bumper bracket perfectly once cut in half, rotated, and splice together.







I'm waiting on an LTR to arrive that isn't custom and pretty cheap.  Once I have that figured out I'll post some more pics.

[Dmod1974]

Did you buy a power window kit ? If so, which one and did it come with everything you needed ( other than the original switches)

Nope, not yet.  None of them are complete and they all use GM switches.  No way was I going to cut up brand new interior panels to mount those!  I have A1 Electric fronts, and if I can't figure out a way to make the rears power I'll probably just buy the Nu-Relics kit without switches.