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Soundproofing the B

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69MGC

69MGC

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Hi folks, I have a question for you all. Tell me if I crazy or not... What I was thinking of doing is sound deading the lower rocker panels, you know the ones that always seem to rust away under the doors. What I was thinking of doing was filling the empty cavity with that expanding polyurethan foam. My thought about this was 1. it would help with noise supression and 2. would keep water out of that cavity and help if not prevent the rocker from rusting from the inside out.

Am I crazy? or what?

What are your thoughts or recommendations? Thanks in advance for the feedback.

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Hello 69,MGC, No you not crazy. A Mechanical engineer friend of mine suggested it to stiffen up the Healey frame. I have another friend down the street who purchased a small Studebaker from a restoration shop, in Kansas I think, and it came with the frame filled with foam.It does take a particular type foam but it is feasable to do.Just do not have a crash---FWIW---Keoke
 
Don't use the expanding foam found in home supply stores and sold as crack filler - that stuff draws moisture like crazy and if you thought your rockers rusted fast before, just wait! Auto suppliers like 3M make structural foam, often called "pillar foam" that is designed for the purposes you describe and won't draw moisture.
 
Having just completed a complete sill replacement on my B, I think it would do nothing for sound proofing. My suggestion would be to use Waxoyl or Penetrol to ward off the tin worm. My thought would be if there is rust in there, the foam would do nothing to stop it. It would just make repairing it properly later that much more difficult. Sounds like a DPO move to me.
 
Well the topic is "Soundproofing". Controlling sound requires that we be able to change the characteristics of the noise,stop it from ecoing,reverberating and reflecting to name a few characteristics. Filling the Cills with foam will satisfy these requirments.However I do not think Waxol qualifies for this application.---FWIW---Keoke
 
If you really want to sound proof, what don't you apply truck bed liner to the floor pans and other structural points around the tub. I plan on putting tinted bedliner on the entire bottom of my car to help with sound and rock chips. Another idea would be dynomat under the carpets.
 
Steve_S

Maybe I'll be able to take the B out on the lake when done, LOL

Seriously though, I just want to make the car cockpit less noisy on the road and sound a bit more solid. I know, I know your going to say "with the top down it's nothing but noise, so what's the point" good point. Every little bit helps though.

Thanks.
 
Fill the sills with foam and the next person who has to do any repair work in the area will not be happy. The DPO of my BGT filled the cubbyhole next to the pedal box and around the hood hinges with the spray foam. Took me days to clean the area up for a respray. Never was able to get one of the hinges out. NOTHING cuts the foam. Try to weld/cut next to it and you will have a big fire and maybe destroy your car. Don't do it!
 
Gerry is exactly right. It would have been insult added to injury to find foam in my rusty sills. They were a bad enough cob job as it was...
 
Kev,

You are right in order to lower road noise you must install sound deadening materials. All new cars have it all over the place and the first problems with MG (and others) is that at a point in time they were rebuilts with new floors and there is no insulation anymore.

No insulation will have your car sound like sitting inside a bass drum when the top is on.

I insulated my car completely and the difference is really big (specially since I am running a modified engine with headers).

I have removed the whole interior and installed a product from a company called B-Quiet all over the floors, back, door skins and so on.

I took some pictures that I will try to find back.

As for the Foam I would not use it altough it can be found today in all luxury cars. The Waxoyl is totally useless
 
Thanks for the web site regarding b-quiet. I think that's the way I'll go. They seem to have pretty good products. Thanks again to all of you for the feedback.
 
As promised here is the picture with the B-Quite material installed
 

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Waterproof? Water resistent at best. Common boat construction is fiberglass over a balsa-ply substrate...and common repairs are for rotted balsa-ply substrate. Encapsulation of the replacement wood and foaming are common repairs.

I'm not saying it would be the best in a B's sills, I would think a thick asphalt based sealant, rubberized mats or Dynamat would be the way to go (even in side the doors).
 
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