Author Topic: noise control (Read 4486 times)

subsonic · « **on:** July 07, 2007, 10:03:50 am »

So lets say you want to keep your ride quite. If you had a empty engine compartment, and had a new engine to go in, what would you add for noise suppression? I am talking about matting or coatings, stuff like that.

OM617 · « **Reply #1 on:** July 07, 2007, 11:11:20 am »

A gas engine.

Benjamin · « **Reply #2 on:** July 07, 2007, 12:21:32 pm »

gas engine is the best way, i ever installed my timing belt wrong on a diesel, the car had no power but it was realy quite, no vibrations etc

anyway, i dont know, i think matting will do a good job if you look to newer cars, they are also quite inside

Greetz, Benjamin

rabbid79 · « **Reply #3 on:** July 07, 2007, 01:43:35 pm »

You could add the under-hood sound insulation if you don't already have it. Also softer motor mounts would help.

foxracer1 · « **Reply #4 on:** July 07, 2007, 02:24:07 pm »

I would just go with some heavy rubberized undercoating or something like that maybe a mat for the hood. It depends on how much you want it quiet versus adding a bunch of weight.

Plus the matting stuff traps oil and grime. I like to power wash the engine comparment quite often and the matting usually dosen't like that. But i haven't seen how the aftermarket matting handles water.

Black Smokin' Diesel · « **Reply #5 on:** July 07, 2007, 09:36:19 pm »

Bedliner or undercoating in the engine bay, dynamat the firewall, floors, roof and front doors.

What car is it? MK1, MK2? if so you're out of luck, they are noisy and whatever you do, they'll always be.

clbanman · « **Reply #6 on:** July 08, 2007, 05:00:01 am »

I have some stuff sold as Millenium Metal that I'm going to try under the hood. It's perforated aluminum used for sound suppression. I figure if you can stand directly under a MTU Detroit Diesel V16 at full song and carry on a conversation without yelling, it must work fairly well. There is a lot more involved in getting the sound suppression down to this level, but the basic product works well. We use tons of baffling and control all openings in the engine compartment. One thing we found on the trucks that I'm not sure would apply to automobiles is that a large amount of the noise is created or escapes through the rad area. Another major point is areas underneath the engine. If you do everything you think of above and beside the engine, you still won't cut the noise all that much unless you do something underneath. Case in point, roll down your window and pull up beside a brick wall - the increase in noise is what is bouncing off the ground and toward the side of the car.
http://www.aapusa.com/millennium.htm

rabbid79 · « **Reply #7 on:** July 08, 2007, 09:11:41 pm »

Ok, try something radical like noise cancellation technology. Microphone in the engine compartment, invert the wave, play through an amp and speakers. Same technology used in noise cancellation headphones. Lotus also used this on some of their Esprits since it was a high-strung four cylinder just behind the driver making tons of noise.

Darth Garry · « **Reply #8 on:** July 09, 2007, 05:30:56 am »

I bit the bullet and installed a gratituous amount of dynomat and liner. It definately made a huge difference. Now when cruising down the highway the wind noise is much greater than the engine, all I hear is a gentle hum.

Another big difference is having the hood insulation installed. It helps both thermally and with sound. There is a very noticable difference without it installed.

Here are some pics of my dynomat install (ignore the cat photos on the top)

http://www.notinteresting.com/photoalbum/040711truckdoza/index.htm

Garry

BlackTieTD · « **Reply #9 on:** July 09, 2007, 06:51:53 am »

Quote from: "rabbid79"

Ok, try something radical like noise cancellation technology. Microphone in the engine compartment, invert the wave, play through an amp and speakers. Same technology used in noise cancellation headphones. Lotus also used this on some of their Esprits since it was a high-strung four cylinder just behind the driver making tons of noise.

:lol: best post in this thread. haven't seen this one mentioned before. nice.

subsonic · « **Reply #10 on:** July 09, 2007, 07:35:04 am »

Gas engine...hmmm. You slay me, very dry, nice wit :lol:

Microphone.. well, my neighbor does have a lotus I can boost one out of.

Yep, it's a mk II golf 4-door. It is not so bad on the highway, but man, I need to shut the thing off if I pull up to a drive through lane at the bank or the coffee shop.

"Good morning, can I take your order?"
CLACKETY CLACKETY! "Yes I would like a large coffee please" CLACKETY!
"What?"
PUTT PUTT CLACKETY CLACK " A Large coffee."
"What? I cant hear you sir"
Grrrrr. :x

What is the difference between the dynoliner and dyno mat? I was looking at something along this line.
Do you have to worry about moisture with that stuff? I was wondering about the photo I saw with the application in the door.
I will look them up on line to read up on there product.

Anyone else use stuff like this? Any long term use comments?

Darth Garry · « **Reply #11 on:** July 09, 2007, 08:53:50 am »

Dynomat is a tar like substance with a tin foil like backing. It lowers the resonant frequency of the panels it's mounted on (stops vibrations) adn also stops sound from seeping through. Dynoliner is more of a foam matting that just deadens the sound more. I put both in and then the stock sound deadning on top of that. Besides having a diffucult time getting the carpet to fit in a few spots, the stuff is awesome.

I mounted the dynomat inside the doors (on the outer panels), and then covered the whole door (replaced the plastic cover moisture guard) with dynomat. Since it's tar and aluminum, I figured it would stop moisture as good as celophane.

In the cab, no worries about moisture.

There are many "knock off" products, and I hear many of them are quite good and much cheaper. Since I've been going for the best, I went with teh best, but if it cost half as much and works 90% as well, wouldn't be a bad idea.

Teh only issue I've noticed is I probably have 30-40 pounds of the stuff applied to the vehicle so if you're trying to shave weight it may not be the best answer.

Garry

burn_your_money · « **Reply #12 on:** July 09, 2007, 09:04:31 am »

Easy solution, bump your idle up to 1100. That's where mine always has been. I never have problems at the drivethru and alot of people are baffled when I say it's a diesel.

Darth Garry · « **Reply #13 on:** July 09, 2007, 10:20:59 am »

I was mostly concerned with road noise combined with diesel engine hum. The dynomat/liner did a great job, albeit was expensive. I have my idle around 1000, and agreed it's a lot less shaky/annoying at idle.

Garry

Black Smokin' Diesel · « **Reply #14 on:** July 09, 2007, 08:05:26 pm »

Dynomat/dynamat/whatever you call it is very expensive for what it is. Search online, you can find the same stuff for much cheaper. After all, it's just tar and aluminum foil... Maybe try the hardware store for tar and aluminum foil

Author Topic: noise control (Read 4486 times)

OM617