Sound and heat Insulation

There's a lot more to the soundproofing game than I knew when I started this job. Since this is the first vehicle I've insulated completely, I decided to conduct some research instead of simply ordering materials based on the best advertising. I have no reason to become an expert, nor do I need a car that's as quiet as a Rolls Royce, but I don't want a rattletrap either. When I restored my '73 Dodge truck, I discovered that it contained almost no insulation from the factory, so I just covered everything with FatMat. It made a world of difference in quietness, and I hope this car will be even quieter.

What I did learn this time is that despite all the manufacturer's advertising hype, modern cars basically use two types of products to control heat and noise. The one for heat and airborne noise absorption is HDF, or high density foam. It absorbs, deflects and shields against external noises, like engine, exhaust, and road noises that sneak through cracks and gaps. For this part of the project I ordered a 1/8" self-adhesive roll to apply to the firewall and the inner door panels.

The next is CLD, or constrained layer dampers. This product dampens acoustic vibrations in places like floors, roof, and trunk areas. For this, I bought a product called Road Kill that is self-adhesive and foil covered on one side. The thickness of both the foil and the damping material affect the efficiency, but for the areas I'm doing now I chose a thinner material that will fit between trim panels and structural metal. Yesterday I applied it to the inside of the roof and a few places on the inside structure. The supplier recommends that approximately 25% of the surface be covered, but I found that to dampen all the vibration in a large panel like the roof, I had to cover approximately 50-60% of the surface. Now when I tap the roof, instead of reverberating like a Caribbean steel drum, all I hear is a dull, metallic thump. Since the headliner will also help absorb noise from above, I might have overdone the Road Kill, but a few dollars extra at this point beats having noise that would require removing the headliner to fix.

They also make composites that both absorb vibrations and acts as a barrier to airborne noise. I plan to use this on the floors, but so far the prices I've found were too high for my budget. I might just use a heavier version of the Road Kill product I got from Amazon.

Firewall Build...and Another Change?

Finding a way to fit and access the under-dash AC is indescribable fun! It appears %I might have succeeded, but until the dashboard is installed I won’t know for sure if there will be room to attach the hoses to the vents. One thing for certain, when the time comes to replace the heater hoses, or to test the AC hoses for leaks, the dash will have to be removed.

One blessing is that the defroster vent on the car and the one on the AC unit are the same size so the hose doesn’t need and adapter, so some space is saved.

If anyone is considering installing aftermarket air conditioning, I strongly recommend using a smaller unit than mine, or at least one that has better access to all the connections when everything is assembled. If I were ever crazy enough to do it again, I’d probably modify the firewall with a removable panel to allow access from under the hood.

The recent need to avoid heavy work is dangerous in ways other than physical, as I have too much time to sit around contemplating and questioning decisions I earlier thought were etched in stone. The latest involves yet another shifter option. After failing to perfect the pushbutton control to my satisfaction, I had decided to use the early A-body shifter I had on the shelf. I modified it to operate with one cable, but had to fabricate a custom lever design on the transmission end. I was more or less done with that job when I ran across this stock '67 A-body shifter at a good price. Since they are always in demand and can easily be re-sold, I decided to buy it to see if I could make it fit. Good idea or not, it looks easily doable, so I've been redesigning the console to accommodate it.  I think it would look better than the early-A body floor shifter, and the stock mechanical linkage is simpler and preferable to the cable version I had planned. Less important, but a nice touch, the knob design is similar in looks to the stock '56 dash controls.

Guest Post

Construction is still proceeding slowly, so I'll share some photos sent to me by a Norwegian reader who is rebuilding a '55 Plymouth station wagon. It appears to have a very solid base to build on, and like so many cars being restored by Mopar enthusiasts from the Scandinavian countries, the quality of workmanship is outstanding.

He also sent photos of artifacts from the Viking boat museum. The details of their construction and artistry is amazing!

My paternal grandparents are both Norwegian, and I'm very proud of my heritage. Granddad's parents emigrated from Norway in the late 1800s and settled in Illinois to farm, so he was born an American citizen. My grandmother was 17 and her sister 19 when the two of them came to America in the early 1900s and traveled to North Dakota to homestead on the prairie. Neither spoke English, but settled in an area where there were several homesteaders from Norway, Sweden and Finland, so they fit right in.

Thanks for the photos, Geir, and keep us up to date on your '55 project.

Back is Back...Sort of

Recovery is slow, but after giving priority to delayed household jobs...like two acres of rapidly growing grass and weeds...I have been able to do a few things on the car that didn't require heavy lifting or contorting.

I've been concentrating on the firewall since the last order of parts arrived. The battery feed-through is installed as is a re-do of the AC hose mounting. Instead of trying to twist the hoses to fit in the tight space, I cut a bigger hole in the firewall and made a stainless steel mounting plate for the connectors. It works and looks much better.

Still to do on the firewall are clamping points for wires, conduit and cables, and applying soundproofing and insulation material in areas hard to access after the dash is installed.

Lots of time spent figuring the best way to route wires into and through the console. I finally decided so I was able to cut the hole through that cross bracing and install the battery cable conduit. When more parts arrive, I can make a shelf for the fuse panel and seat module inside the console.

I'm not sure which way to go after the firewall. It may depend on the weather, as I'm anxious to get the roof painted and want to move the car outside for the final priming and sanding. The rainy season should be slacking off soon, so that might be one of the next jobs.

I'm also getting close to the point where I can install the engine and transmission. All the little things take time and don't give much feeling of accomplishment, so maybe seeing the drivetrain taking form might give me more inspiration.

Seats

Parts and pieces are arriving, but my back still won't cooperate. More soundproofing materials have been shipped, as have more wiring supplies. They should be here by Monday. While I wait to heal, I've been able to get a few things ordered, and some things picked up locally.

My seats are done and I got them yesterday. I was very pleased with the price and with the color combination I chose. They loaded them in the van for me, but I had to unload them and get them stored by myself. There was no way to avoid lifting and that probably delayed my recovery for another week. I could barely move last night. I'll have to force myself to rest today.

I was hoping to pick up the wiper bezels yesterday, but the machine shop said they could not do the job as there was no way to grip the irregular shaped parts without damaging the plating. I took them home and used a Dremel stone to clean out and enlarge the holes for the bushings. I got the bushings pressed in, but still need to assemble the parts.