Sound Deadening for '60 coupe engine room

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PaulAhnell
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Sound Deadening for '60 coupe engine room

#1 Post by PaulAhnell » Wed Jun 07, 2017 9:00 pm

Has anyone had experience with the engine compartment sound deadening package sold by Stoddard? See the following link. How effective is it?

http://www.stoddard.com/media/catalog/p ... 1-02lg.jpg

I'm looking to install a precut package in my '60 Normal coupe engine compartment. I don't need something that looks "correct", I want something that is effective in quieting the noise and is reasonably easy to install.

I just installed Dynamat covered by a 1/2" layer of felt-tar-felt sandwich on the forward face of the firewall, the floor, walls, and forward bulkhead of the passenger compartment.
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'60 Normal Coupe

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Doug McDonnell
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Re: Sound Deadening for '60 coupe engine room

#2 Post by Doug McDonnell » Wed Jun 07, 2017 10:01 pm

I would guess that even if you just use the Stoddard kit your car will be quieter than they were new due to what you did in the interior. The original NLA sound deadening in the engine compartment was thicker than the currently available standard kit though. In this link you can see a kit I bought from Stoddard in the mid eighties that I have since sold to another member. Jute type backing on the engine and side wall pieces: viewtopic.php?f=13&t=40291&p=251845&hil ... ng#p251845 Others have used dynamat on the engine side of the firewall covered by the Stoddard kit piece.
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Re: Sound Deadening for '60 coupe engine room

#3 Post by Jan Kolm » Thu Jun 08, 2017 12:06 am

The jute-backed firewall mat was a running change during the 1961 model year. My July '60 had the thick tar board for a firewall mat.
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Thom Fitzpatrick
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Re: Sound Deadening for '60 coupe engine room

#4 Post by Thom Fitzpatrick » Sat Jun 17, 2017 2:15 pm

I had a similar issue: I have hearing problems and I'm sensitive to higher-pitched sounds and loud noise in general. I bought some vinyl-backed material from McMaster-Carr and made a custom sound pad which is actually sort of similar to what they used in 911's. It's black with a pinhole pattern that is similar to that of headliners. If someone didn't know any better, they could be convinced it was factory. In any case, it made a YUGE difference in the sound volume in the cabin. I wish I had taken sound measurements before so I could offer concrete numbers. The foam soaks up higher frequency sounds than the dynamat/jute/tarboard/undercoating.

This is the material: https://www.mcmaster.com/#9385K23

I only made a layer from the "step" in the firewall up to the top. In hindsight, I would have made the slots for the hinge mounts shorter. Using the 1" thick material brought the top level out flush with the bottom. I'm still on the fence as to whether or not I am going to do the sides; it will help, but not as much as covering the section of the firewall did.
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1956 VW Single Cab
1957 Porsche 356A Sunroof Coupé
1957 VW 23-window Deluxe
1957 BMW Isetta
1960 VW Panel
1963 Type 3 Karmann Ghia
1963 Mercedes Unimog 404
2003 BMW M3

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Re: Sound Deadening for '60 coupe engine room

#5 Post by jay darlington » Sat Jun 17, 2017 5:16 pm

I believe this material is also available with a lead liner that reduces sound even more. I use to work for a tug boat co. and we used that to insulate the living quarters form the engine room. 2, 16 cyl 3000 hp EMD's make a lot of noise.
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PaulAhnell
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Re: Sound Deadening for '60 coupe engine room

#6 Post by PaulAhnell » Mon Jun 19, 2017 7:59 am

Thank you all for your replies and suggestions.

Thom: the material you suggest looks interesting. The PO installed a closed-cell foam pad (w/o tiny holes) but it isn't very effective. I'll investigate yours further. McMaster's description says it is limited to 200* F. Using one of those Harbor Freight laser guns, I've recorded temps of 275* +/-, especially over the muffler area. I had planned to cover all surfaces so that may be problematic. Dynamat is good to 300*.

I considered Dynamat on the rear face of the firewall and other surfaces in the engine room under the Stoddard kit, in addition to that which I put on the forward face of the FW. The Tech at Dynamat was non-committal as to the effectiveness of that 2nd application.
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'60 Normal Coupe

Thom Fitzpatrick
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Re: Sound Deadening for '60 coupe engine room

#7 Post by Thom Fitzpatrick » Mon Jun 19, 2017 5:27 pm

PaulAhnell wrote:Thom: the material you suggest looks interesting. The PO installed a closed-cell foam pad (w/o tiny holes) but it isn't very effective. I'll investigate yours further. McMaster's description says it is limited to 200* F. Using one of those Harbor Freight laser guns, I've recorded temps of 275* +/-, especially over the muffler area. I had planned to cover all surfaces so that may be problematic. Dynamat is good to 300*.
I only covered the area shown in the pic; the material I used would be inappropriate anywhere near the muffler. On top of that (forgive the pun), I don't know that you will get any useful sound redunction by covering that area anyway.
1956 VW Single Cab
1957 Porsche 356A Sunroof Coupé
1957 VW 23-window Deluxe
1957 BMW Isetta
1960 VW Panel
1963 Type 3 Karmann Ghia
1963 Mercedes Unimog 404
2003 BMW M3

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