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I've place sound deadening material on the inside on the car but will it help to place it inside the door panels. I'm rebuilding the doors this weekend, it would be nice to put the material inplace now. How much would it really help? Has anyone tried this?

Stanley
 

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Yes it helps!

Yels, sound deadening material in the doors helps!Depending on the type you are usind (peel-n-stick or spray-on) I would recommend ccovering at least 10-20 % of the inside of the outer door skin, preferably torwards the center of the panel.

The difference in interior noise is huge.
 

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Generally, the spray-on stuff will be a lot lighter, and will be far easier to apply in difficult area (i.e., not perfectly flat). I'm not talking about generic undercoating, but rather purpose-engineered sound deadening materials. I got a case of spray-on stuff from my friend when he worked at Tweeter (got it at cost), and even then, it's very expensive. But, it seems to do the job, and it does weigh far less. For instance, the guy I got my ITB Ascona chassis from had applied a bunch of extra sound deadening under the hood, the firewall, the doors, the floor, the rear deck area, the trunk lid....I removed over 140 lbs of the conventional type (Dynamat) sound deadening material. Yeesh. My Dad's GT is getting the lighter-weight stuff however, even though the engine will be powerful enough to make up for the extra weight.

Bob
 

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Cheap? We got Cheap!

My firetruck had actual roof shingles glued to the inside of the doors. Not light, exactly, but certainly cheap and effective.

Hey, you wanted cheap.
 

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opelmark said:
140 POUNDS?? :eek: Yeah, that sounds kind of EXCESSIVE to me, too--about 130 pounds too much--so, go nuts
Not as much as you may think. A stock Opel has approx. 40-50 lbs of sound deadening and undercoating (I know, whenever I strip a car for racing I weigh what I remove). So this car had 'only' an additional 90-100 lbs. I remembered the brand of sound deadener I had used on the GT before, it was Rockford-Fosgate. Light blue stuff. It tends to be porous, so it's for interior use only. I sealed it with a coat of POR-15, so it doesn't rub off from abrasions and make a mess.

Bob
 

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opelmark said:
It seems to be another "trade-off" situation, where the car can either be faster, or more comfortable/quiet, but you can't really have both
SURE you can. Just add all the insulation you want, and drop in a small block Chevy.....(okay, I'm just kidding).
However, the way to go for 'serious' power is turboing a large displacement Opel motor, and using modern programmable fuel injection. Smooth idle, great torque, tons of power, and driveability. Downside? Money of course. But speed is addictive, and once you've started driving it, you'll want more boost, then less weight, then bigger tires, then more boost.....


Bob
'Putting a WRX IHI turbo on my 1971 Ascona wagon'
 

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I have no problem with Gary reprinting it. It might be a good thing to have on the 'downloads' section. I'd probably make a few amendments or changes. I really think the only way to go now is with welding the intake....it's so much safer than epoxy in the long run.

As far as the turbo route, the turbo recommended depends on the reality of what kind of power you intend to run. As nice as low compression pistons *should* be for a turbo motor, the fact is the low comps are weaker than the flat-tops. For some reason, the ring lands fail even with 65 hp. I wouldn't trust them for boost! Turbo selection will depend on engine size, rpm range, boost levels to be run, fuel octane, volumetric efficiency, and the actual hp to be attained. I can guesstimate the turbo type to be used, but the true trim sizes and AR ratios are best left to the pros. I know an engineer at Garrett who's been very helpful, he e-mails me the correct turbo to use based on all my figures I feed him.

I happened to fall into a deal with a 1400-mile old WRX turbo, and it so happens that particular turbo can run up to about 17 psi boost before compressor surge is a problem, and will support about 300 hp. It also just so happens a 2.0 litre WRX engine has a similar bore/stroke ratio to an Opel, so it should be a good match for the Opel and have similar lag levels (except with 1000 less pounds of weight to carry around). I'm targeting 260-275 hp with a 2170 cc engine and 15 psi boost. If you want to continue on this thread, lets get onto the appropriate header!

Bob
 

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Don't forget ebay too. I recently bought two gallons of the dynashield spray (application gun as well) for $150. The specs say that 12 oz. should be enough to do 4 sq. feet, so I'm going to do my GT's, then my diesels. Every once and a while, you'll see it come up for auction.
 

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How's this:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=3002593032&category=14932

That price quote for retail is a complete load of crap though, That jug (same size as one I bought) is about $300-$350 retail. In addition, when this stuff gets cold, it tends to seperate, so shipping from MI may be problematic. My understanding, though, is that while the cold will ruin the spray cans of this stuff, the jug can be warmed and re-mixed. Good Luck,
 

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Noise Killer

I checked out the website for NoiseKiller, but could find no price list or product list. I even tried their "[email protected]" contact button, but the message was returned as an undeliverable address. How did you order this stuff? It looks as though it could solve some problems for the Street Rod, as well as my other Opels.:confused:
 

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1970 Opel Gt - Purchased July 1972 - Chartreuse - restored - 3000 miles as of 02-16, 2021 -
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I've place sound deadening material on the inside on the car but will it help to place it inside the door panels. I'm rebuilding the doors this weekend, it would be nice to put the material inplace now. How much would it really help? Has anyone tried this?

Stanley
Speaking of Sound Proofing, I finished the cabin sound proofing today - I used a product called Peel and Seal which is a flashing material typically used around windows, comes in rolls that are 6 inches wide and 25 feet long. Including the door panels, the floors, and the floor area under the storage area, this project took around 9 rolls = $171.00 - I used three layers. The product is made of a rubber material that is self adhesive and the top is aluminum, there is no odor with this product - this newly added sound proofing material is on top of the black square sound proofing material that I purchase from Eastwood in the late 90's, and applied to the cabin flooring areas, so I would think that with the combination of the two products it should register a difference, will have to advise on the results down the road. I also added a dense foam pad to the back of the carpet which adds a little comfort as well as a touch more sound proofing. Also in the late 90's I used a spray on product under the 4 fenders and recently covered that with a truck bed liner brush on product that hopfully added some additional sound proofing as well, I prefered the truck bed liner product as it seemed to cover better than the spray on product. I have not added anything to the bottom of the car and don't plan to, at this point. If I were starting from scratch with a completely stripped down car, like mine was in the late 90's I would have done a lot of things differently instead of going back and doing them after the fact - wish this forum had been available then as I have learned so many useful things.



436669


436670


Completed project:

436671
 

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Speaking of Sound Proofing
19 years ago, yes. :p

Somewhere in the world, the night this thread was posted, a young man was born. While Stanley_P was pondering sound deadening, a mother gave birth. That baby has since graduated high school right before the pandemic hit and started college, remote classes. He works part time in the evenings as a security desk guard at a condo highrise not because it pays well, but because it's simple and he can get his studying and lectures done at the desk. He's been with the same girl since 10th grade so he's thinking of proposing to her and wondering if the the ring is worth it or if he and her should be be practical and go on an engagement tour instead now that Covid restrictions are lifted.

Meanwhile you're like "Hey since we're talking about sound deadening..." a conversation that occurred literally before he was born.

There's another version of this story with an 18-year old, and the conversation instead occurred while he was being conceived.

That and many other things happened that night, 19 years ago.

...

On a related note, I saw a couple rolls of this stuff at a thrift store last year. It looked like a lead (actual lead, says so) sheet with rubber on either side. Maybe 1/8" thick total. Really heavy. Says it's sound deadening. It's probably decades old. I bought one roll to do tests on and intended to ask the wisdom of the crowds here on whether I should buy the second roll, but when I went back the next day they'd thrown it out.
 
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