Just drove my 79B-V8 (3.9L Rover, T5 NWC Camaro tranny) from Milwaukee, WI to Columbus, IN (400 miles). Too much fun, except now I want to do some work on road noise. Looking for good suggestions on interior insulation (see lots of that in "how it was done" articles) and convertible cover (mine is nice and dry, but probably about as thin as you can buy!). Any other suggestions(tires, maybe?)?
Lizard skin, the best and lightest of all insulation.
I used Dynamat
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I used lizard skin - both heat and sound control. Then, I also used EZCOOL everywhere except the Florida board areas in front of the seats. There I used KoolMat because it's way more durable. I don't notice any road noise being an issue.
Loud pipes eliminate road noise.
I was at the SEMA show a month ago and looked at several of the insulation manufacturers there. I was surprised how heavy most of the products were. The mat products were very dense and even the Lizard Skin buckets were quite a heft to pick up. Do any of you know of a light weight insulation product that works?
Glass micro-spheres are incredibly light and exceptional insulators. Your choice of a binder will determine weight and other properties but you can fine tune the mixture for your preferences and your application method.
Jim
The best noise attenuation product is one that has a random jute material (3/8"' - 1/2") covered by a dense masticated rubber backing (typically 1/8")
Sound waves are absorbed by the jute and those that travel through are reflected back into the jute by the rubber backing. Take a look at typical noise packages installed by the auto OEM's and you'll get a feel for the construction.
Under dash panels 453-863 as sold by Moss), constructed similar to above, are worth their weight in noise control.....and don't forget around the shift opening - a major noise entry point and only mere rubber boot to control noise!
EZCOOL is very light. http://www.lobucrod.com/
QuoteEZCOOL is very light
Alas, Rob, the best noise attenuation materials are usually dense and heavy (think lead!)
Ear plugs. Always wear them on the Interstate.
QuoteEar plugs. Always wear them on the Interstate
For top-down travellers - take note of this message.
None of us practice it, but it is good advice.
QuoteLoud pipes eliminate road noise.
Yep, that and wind noise around the door/window seals.
QuoteAlas, Rob, the best noise attenuation materials are usually dense and heavy (think lead!)
According to the Lizardskin web site, the sound control weighs 13.71lbs/gallon wet, and covers about 45-50 square feet. Dry, it's about 0.23 lbs/squarefoot. The heat control weighs 5.59lbs/gallon and covers about 50 square feet. Dry, it's about 0.06 lbs/ square foot. Looks like less than 20 lbs/car?
I don't know how Lizardskin compares to other material, but the heat coating does a great job. My problem with noise is the wind noise with the windows up and the exhaust sound with the windows down.
QuoteEar plugs. Always wear them on the Interstate.
That, and learn sign language if you're traveling with someone. Be that as it may, I'm unwilling to give up the beautiful music coming from the exhaust pipes. I keep thinking about changing to a quieter system, but I just can't bring myself to do it. Maybe some day when I'm old, but not now.
QuoteNone of us practice it, but it is good advice.
'Cept me? I discovered many years ago that wearing ear plugs on long, top down jaunts to the V8 meets greatly reduces driver fatigue.
QuoteQuoteEZCOOL is very light
Alas, Rob, the best noise attenuation materials are usually dense and heavy (think lead!)
Makes sense. I don't notice road noise so it's probably the Lizard Skin?
Jim
I have heard about using micro spheres mixed with latex paint for a poor man's Lizard skin. Any first hand experience?
Rob
Thanks for the link, I ordered a sample
Dan
I had no idea the material lost so much weight when it dried. I was just surprised how heavy a 5 gallon can was at the show. I have no top so wind noise leaking past the windows isn't an issue but I have filed away the earplug advise.
I used the microspheres in the undercoat, same urethane paint as the finish, as well as inside the tub with cheap acrylic enamel. It sure helps with sound deadening, but heat not so much, I ended up having to wrap the exhaust from the headers back to where the spring perches were to keep it down, and my feet still get toasty. There is a post on the H.A.M.B. about peel and seal, a cheaper alternative to the Dynamat and others out there that they are swearing by.
Peel and Seal is roofing patch,sold at Home Depot! The Cobra guys use hot water tank insulation ,also found at Home Depot!
Thanks for the lobucrod source Rob, I think I might try it, and for me it's local. I'll give them a call and see if it's OK for me to do a will-call.
Paul
For areas that are flat and will not see much contact or movement you might try the foil faced rigid foam insulation sold at building supplies. Available in 1/2" and possibly thinner, it is very good heat insulation and a fair sound barrier. Don't think you'd want it under your feet but under the seat and other places it would do good I think. Heavy aluminum tape would be handy too.
Jim
Stock Healeys are notoriously hot and V8 ones moreso, so I focused my efforts on heat reduction rather than road noise. It seems to have worked, but because I have so many levels, it's hard to tell which one worked best or whether it's a combination. I used the poor man's Lizard Skin of microballoons mixed into DP40 primer as described here:http://www.hotrodders.com/forum/alternative-lizard-skin-103610.html I wouldn't be too concerned about the weight of Lizard Skin. The microballoons are really light, when you're picking up a pail of the product, the weight is in the paint (which you'd be applying to the car anyway) rather than the microballons. The microballons are like talcum powder and a bag this small mixes into a gallon of paint:
(http://i81.photobucket.com/albums/j222/healeyrick/IMG_0220.jpg)
You can get them from www.hytechsales.com.
What works for heat insulation doesn't necessarily work for road noise, though. Lizard Skin sells two products, one for insulation, the other for sound. Generally, the sound insulation is some form of heavy rubberized substance. As Graham suggests, go to the junkyard and look what the manufacturers do. Most cars have a rubber mat glued to the floorpan. Part of road noise also comes from vibration of sheet metal and you can decrease this by strategic application of products like DynaMat to interior door panels, trunk lids, etc. Needless to say, it's easiest to do this stuff during the build rather than at the end. You can see what I did for heat insulation in my project journal: http://forum.britishv8.org/read.php?13,8264
Quote
For areas that are flat and will not see much contact or movement you might try the foil faced rigid foam insulation sold at building supplies. Available in 1/2" and possibly thinner, it is very good heat insulation and a fair sound barrier. Don't think you'd want it under your feet but under the seat and other places it would do good I think. Heavy aluminum tape would be handy too.
Actually, I have 1" thick board insulation sandwiched in between inner and outer sheets of the tunnel and firewall. The exhaust runs up inside the tunnel so the floorboards shouldn't get very hot - he says hopefully.
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Plastic wheel well liners are available for MGB - ref: http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=67616 - but I haven't yet seen anyone use them. Assuming they'll fit your (modified) MGB, I suspect they might reduce noise a lot, especially if you drive on sandy or wet roads.
Dynamat is just a fancy version of the mastic sound deadening material that OEMs have used for 50+ years. What interests me is that folks tend to apply so much of it despite its heavy weight and high price. They use it in ways an OEM would never consider. In an OEM application, the mastic is typically a rectangle of material applied to the center of a panel. Using more provides rapidly diminishing returns. OEMs know that an embossed section or a seam stamped into the sheetmetal is a more elegant way to reduce vibration and/or shift its frequency. A welded-on or bolted-on stiffener might be another option.
Larry Shimp's GT is by far the quietest MGB I've driven. - Ref: http://www.britishv8.org/MG/LarryShimp.htm - I'm sure its interior noise level is closer to a Lexus than it is to my deliberately obnoxious GT. Hopefully Larry will chime in soon with some suggestions. IMHO, he was probably clever to focus on his exhaust system installation. Specifically, Larry used flexible couplings just downstream of his headers and compliant exhaust mounts throughout.
(http://www.britishv8.org/MG/LarryShimp/LarryShimp-A4.jpg)
(http://www.britishv8.org/MG/LarryShimp/LarryShimp-AF.jpg)
On my car, vibration at the muffler is mechanically transferred into the floorboards and that isn't a good thing. Better exhaust mounts will be both cheaper and (probably) more effective than new mufflers.
FWIW, I wear ear plugs when traveling on highways but not around town.
Just called Mike Harbor and ordered some EZ-Cool Mat. I'll let you guys know if a 70 year old can glue the stuff down.
Paul