Roadster Interior Noise Reduction

SonnyC

I was unhappy with the road noise at high speeds in my roadster. I did searches in the forum and couldn't find where anyone with a roadster had attempted to reduce the road noise level. Tons of posts about coupes with detailed descriptions and photos but no roadster. After reading them all and confering with Guard Dog, I did a modified version of the coupe sound control on my car today.

Before any of you comment about turn the stereo up or buy a Borla CBE, I like engine noise and the car has a Stillen CBE system but I found the roar of the road a little annoying at high speeds and it made it difficult to have a conversation at normal speaking levels.

Today I installed dynamat extreme over all of the metal surfaces of the trunk floor and walls, exposed fender wells in the trunk and trunk lid. After installing the dynamat I stuffed the voids with poly batting and reinstalled the upholstry.

Next I put a layer of dynamat on the rear fender wells that are under the boot in the interior. It was very easy to do. Just open the top to about half way and lift the pleather material that covers the top motors and wiring and you can access the fender wells.

I then removed the door panels and intalled dynamat on the metal surfaces of the door. This was a rather difficult job when doing it for the first time because someone had to hold the door panel while the install was being done. The side airbag has an electrical connector that was a little scary looking and I didn't want to risk blowing the bags so I left it alone and just had my son hold the panel.

While I had the door panels off I replaced the Bose speakers with a set of Alpine two ways and replaced the door panels.

After a test drive, I was pleased with the results. The overall noise level was substantially down. I would estimate the decrease at about 30%. You still get a lot of the high frequency pings from rocks and debris coming off the tires and hitting the fender wells but they are much less anoying than with the dynamat. The low frequency drone sound is all but gone. I plan on putting on a set of Michelin Pilots when I wear out the OEM Stones and that should help even more.

I would recomend the install to anyone who is interested in a quieter interior sound level. I used six sheets of dynamat and it took my son and I about four hours to complete the project.

The new speakers sound great too. The midrange and upper ranges are much clearer and crisper than with the paper cone Bose models. The Alpines I installed are power hogs and the stock Bose stereo drives the small speakers in the dash pretty hard. It makes for an interesting sound quality that I am happy with. There is still not much base but that will not change unless you put an amp and a subwoofer in the trunk. Driving base is not that important or desirable to me so I will probably leave the stereo system alone for now.

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Stillen CBE, AFE Drop Ins, Hyper Black Rays, 20mm Spacers, Black Pear Emblems, 25% Tint