Engine sound dampening products

[beernutz]

I have foam dampening material attached in the inside walls of my engine compartment as well as the back of the carpet-covered wood dividers which separate the passenger area from the wells on each side of the engine.

The foam is pretty old and even if it weren't I don't think it is all that effective in reducing engine noise so I am looking to replace it with something that works better.

I have done a bit of research and found something called Quiet Barrier as well as a thicker and supposedly more effective (and expensive) product Quiet Barrier HD.

Does anyone have any experience with these products? Is there anything else out there I should consider? I am working with an effective budget of around $200 for this fwiw.

 

[streetdoc432]

I use a brand called Dynamat for my stereo installs. They make one designed for the car firewall that has a heat reflective silver liner on it too. Check JC Whitney website for a better $ on it.

 

[270SLX]

The McMaster Carr and Grainger catalogs sell sound absorbent materials in sheets and in trowel-on forms. When I do my boat, I'll use an octave band sound level meter to determne the frequency spectrum of the engine noise. Then, I'll select an oil-resistant noise absorbent material that will attenuate the dominant frequencies of my engine. I'm guessing I'll go after the 250 Hz to 1000 Hz noise. There are kits designed for boat engines and that would probably be a short cut but heck, I'm a safety guy so I do it the hard way.

Dennis