MG Sports Cars

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:[www.hotrodders.com] 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:



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: [forum.britishv8.org]

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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.

Plastic wheel well liners are available for MGB - ref: [www.mossmotors.com] - 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: [www.britishv8.org] - 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.





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