EO I'll send you a PM once I measure how much I have.

NA6 not sure how you plan to install it under the dash, since it needs nice solid/clean surfaces to stick to, as well as the car has insulation under there already. Pretty much impossible to do it under there (if you mean removing the dash like I did) I'd suggest multi-cell foam under there, not fatmat.

 

Dash will be out. And I meant on any of the larger flat surfaces I find, like the back side of the glove box, or equal in size. Any of the other light weight plastic parts that are prone to vibration that have enough surface area to stick a small piece of fatmat on. I think fatmat on the firewall will help more than anything else in my case. As well as closing off the few small holes that are open between the engine compartment and the inside of the car.

 

If you don't go with the Magnaflow, the Racing Beat single exhaust is very quiet. I was hoping it'd be a bit louder on my 99' with the Flyin' Miata midpipe but it just doesn't have the volume I'm personally looking for at full blast but it might be just right for what you're looking for.

 

Instead of making the car quiet you can make everything quieter. No amount of insulation will really do much for noise reduction in a miata.

I have used these etymotics for several years. Even with the hardtop on and the windows up, freeway noise is too high for me. They are inexpensive and effective, and pretty comfortable, but can sometimes cause the slight earache that wearing any earplug with expandable materials can give you after a few hours. Etymotic ER-20 earplugs.

Now that I am finally tracking the car consistently I have gone the custom, molded earplug route to be able to use them with the helmet. The molds took all of 20 minutes. I have had them for a week now, worn them for about 15 hours, with no discomfort at any point. Very effective noise reduction. Do a search for a Willoughby's dealer near you. If you want, you can have them mold earbuds into them. This is apparently a common request.

 

FWIW, this is illegal in more than a handful of states. They want you to be able to hear emergency vehicles.

 

http://www.raamaudio.com/products/En...and-Stick.html

 

Yup, I actually have a big sheet of that stuff. Good stuff

 

Will be buying some of that ^. Looks useful for a lot of things.

I may be crazy, but I swear that after only applying fatmat to the lower part of the door on the passenger side, and to the spare tire well in the trunk, I can already hear a difference. I can't wait to have the whole interior covered. My door actually closes with a clunk now, not a soda can noise or a steel drum.

 

Doing the doors makes a huge difference, you're not crazy. Definitely one of the more important areas to cover

 

Isn't it sweet? I did my car during the swap due to the extra heat. Only a few spots where the heat is still bad, but the C5 was still 10x worse (the tunnel), so I've learned to stay away from the areas.

 

I wish I could get the door apart and cover 100% of the shell, but I can only reach the bottom 9" under the bar running the length of the door. Above that there is window mechanisms and brackets in the way. A LOT of door left that is still tinny sounding, but it's still 10x better with just two layers in that area. Going from one door to the other it is very very noticeable. Ting ting, thud thud.

I have to figure out what will be best for the floor. Since my roll bar is removed, I have quite a few holes in the floor that are open to the outside. I'm scared water will splash through the holes and get under the mat and rot the floor out. Or will the tar push through the holes enough to seal it? Not sure what else to do short of putting bolts with washers through each hole. Then I have to deal with putting a bar back in eventually, probably using the same holes. So the mat will have to be peeled up in those spots to let the bar sit low as possible for hard top clearance.

 

I was actually thinking of covering the whole door right under the door panel, not completely inside the skin like you. That way the whole thing is covered. Thoughts?

 

I had a 3" resonator installed yesterday and was pleasantly surprised how much nicer the car sounds now. Lower tone and not as raw as before. Definitely quieter. I'm guessing I will still be itching for more quiet, in time, and will end up with the magnaflow 22x11x5, 3" in/out.

 

The custom molded silicone ones are seriously awesome. A friend of mine and I got them done at a gunshow and I used them for everything now. I spent 3 summers operating a shooting range and he photographs motorsports so these things are well tested.

Christ man, what are you using for an exhaust that you wear these on track?

You should be able to get small rubber body plugs from the VatoZone or even Napa. Clean and seal with RTV if it freaks you out, just don't mat over the plugs. I had to do this to my 66 Mustang back in the day, PO drilled a bunch of holes in the tinfoil floor for whatever reason.

It helps. Anything that gives the door mass will help it not resonate. We did what you describe to my friends 95 Integra and it helped immensely. That was probably the worst car I've ever been in for road noise, even in its stock configuration

 

The only downside to this is if your power window sliders or motors fail, you'll have to cut the mat out to access the tracks and motor. Unless the product you are using is easy to remove and tacky enough to re-apply.

 

True. I guess Ill dig into there and see how much of it I can cover on the inside like NA6 was saying

 

I would add diagonal strips about 3" wide by however high you can get on the exterior door skin to add mass, while not being excessive, and then adding a foam layer along the entire inner panel of the door. And, hell, since you're already in there, go ahead and replace the sliders and grease the tracks so you don't have to worry about it down the road.

 

If you already have the door panel off its super easy to get the entire door skin covered above the door re-bar. It takes three screws to get the window glass out. With it out you should be able to reach everywhere in there. Doin the full door skin and the areas just behind the door panel is ****. I did one and didnt have time to finish the other the same night. On the way to work, all high way, it was so deadened on the one side I felt like i had a clogged ear. Hush on one side football croud on the other. You can also use "great stuff" to fill in the open voids between panels and alot of the trunk area and around the fuel tank. Ive seen people fill in the hood and trunk support braces too.

 

It's not my exhaust, that's stock. It's either a) the wind noise with the windows down at 100+ or b) the Z06 in front of me with his straight pipes pointed right at me. Today was the first day I tried the molded plugs with the helmet on track. I could actually hear my exhaust better.

RE: emergency vehicles, I'm not worried there. With the etymotics in I feel I have a better chance of hearing sirens. They really cut down on the ambient background noise. The unscientific but still an empirical evidence test is that with the etymotics in on the freeway, I can hear the radio clearly at a lower volume setting than with them out. And - everyone in the hearing center assumed I was a motorcycle cop.

For freeway use I have discovered the molded plugs I currently have aren't very good. They aren't silicone, they are of some rigid plastic material. There are some frequencies of road noise at highway speeds that seem to set up a resonance in them. The etymotics are much better. I'm going to go back and check on silicone.

 

I use Etymotic ER-20 earplugs for long top down drives, and for concerts, clubs, and loud movies.