A more quiet exhaust

[IZwack]

I want my exhaust to be more quiet. I know this is going against the norm but I like quiet ones more.
My current setup is purely stock - stock exhaust - stock resonator.

So how do i turn down the decibles?

Would welding on another resonator from say another Explorer help (for a sequential resonator setup) ?

 

[briwayjones]

Woah your stock exhaust is too loud? There has to be something wrong with it if you're complaining about the noise from it? If there's nothing wrong with it making it louder I wouldn't now how to make it more quiet.

 

[IZwack]

Woah your stock exhaust is too loud? There has to be something wrong with it if you're complaining about the noise from it? If there's nothing wrong with it making it louder I wouldn't now how to make it more quiet.

Its not too loud I just dont want to hear exhaust.
In fact, I shouldnt be able to tell tat the car is on-- Minimize noise pollution

For example, when taking video of trail runs -- all you can hear is the rumbling -- its like WTF Man.. WTF!?!?! SHUT THAT THING OFF!!! :frustrate

So, would adding another resonator help?

 

[briwayjones]

Do you have a cold air intake?

 

[IZwack]

Do you have a cold air intake?

Not a real cold air intake - but I have the umm KKM.

But thats a good point - I do recall the KKM increasing the decibles after installation. But it did add some "umph" to the vehicle so I don't think I'm going to get rid of that.

What I'm focusing on is another resonator

 

[briwayjones]

Yeah they do make it louder. Maybe another resonator will help. I wonder how much it would restrict the flow?

 

[IZwack]

I wonder how much it would restrict the flow?

I've read somewhere that resonators restrict air flow very little - if at all because it is an empty chamber.

The only energy is takes from the exhaust is used to create the cancelling wave (same frequency but 180 degrees out of phase)

 

[BrooklynBay]

I remember reading an article about an ultrasonic noise canceling system which used ultrasonic transducers to cancel noise. It had transducers all around some sort of muffler. One would act as a microphone, and send the signal to a DSP (digital signal processor), while the DSP would send out an inverted sound wave to the other transducer. As the sound varied, the DSP would compensate. All of these things work in a lab, but some how never make it to the market.
It reminded me of another gadget they once came out with in a lab. It was a HV (high voltage) generator which would convert gasoline into a plasma, and send it to the fuel injectors. It increased gas mileage, made the engine run smoother, reduced emissions, and enabled oil in the engine to stay clean longer without as many carbon deposits accumulating. What happens to all of these things?

 

[IZwack]

What happens to all of these things?

Globalism driven by free-market economy probably decided its costs were too high

 

[section525]

Run a dryer exhaust tube from the tail pipe into the cab of the truck and go on a long drive to see if that makes it any quieter.

 

[IZwack]

Run a dryer exhaust tube from the tail pipe into the cab of the truck and go on a long drive to see if that makes it any quieter.

etf !? hey my neck hurts- i need a massage

 

[dogfriend]

Run a dryer exhaust tube from the tail pipe into the cab of the truck and go on a long drive to see if that makes it any quieter.

You're such a humanitarian.

 

[section525]

I do what I can.

 

[Stic-o]

Nah he should just close the garage door and listen for little while, it will get quite...and dark!

Really though that KKM really adds some noise. I'd say you get more noise from the engeine then the exsaust stock with the KKM.

 

[rookieshooter]

For example, when taking video of trail runs -- all you can hear is the rumbling -- its like WTF Man.. WTF!?!?! SHUT THAT THING OFF!!! :frustrate

So, would adding another resonator help?

WTF is right. The best analogy I can come up with, is this. Videoing a trail run with no rumbling, would be like really doing a women justice. I mean your throwing the hydrolics to her. She's salavating and her eyes are rolling up to the top of her head. But she is Not Moaning this is not good.
So, would adding another resonator help. Not in this case anyway. On second thought, mabe it would.

 

[IZwack]

You guys are all over the place here (!!) -- with the dryer hose and sexual connotations

Anways, I was thinking for a few minutes (a rarity) and I'm not sure the second resonator with the same dimensions would help because assuming the first one is working properly, then it should have already attenuated the frequency bands its designed for. So a second resonator wouldn't be very effective because it won't really have much to work with. Of course thats assuming that the effeciency/effectiveness of the first resonator is pretty high. If its fairly low, then of course a second resonator would help quite a bit.

 

[rookieshooter]

this may shed some light on resonance


http://www.umanitoba.ca/faculties/arts/linguistics/russell/138/sec4/resonanc.htm

 

[IZwack]

this may shed some light on resonance http://www.umanitoba.ca/faculties/arts/linguistics/russell/138/sec4/resonanc.htm

Thanks!

I do know a tiny bit about harmonics in relation to the length of the wave but I guess my questoin is, how effective are the resonators on vehicles?

I guess one way of building a second resonator w/o knowing how effective the first resonator is is to make the second resonator adjustable (its length) -- weird but interesting.

The other interesting thing that popped into mind is that the three different engine sizes (4.0, 4.6 and the 5.0) should have different resonator dimensions since the resonator's volume is a function of engine displacement (and number of cylinders). Whether or not this is true on our vehicles I dunno, the two Explorers (97 and 98) I have access to are both 4.0 sohc so the resonators are probably the same sizes. The cost of building three different resonators is probably pretty low but the automotive industry is well know for taking short-cuts

 

[rookieshooter]

The adjustable resonator sounds interesting. Reminds me of how we use to start off with a long collector at the end of the headers. Then we would start cutting off untill we saw a gain in horsepower via ET time slips. We wanted the pulsating pressure waves to scavage the cylinders for more fresh air. Sounds about like the same thing. Waves are waves

 

[BrooklynBay]

Maybe the extra loud sound might be from an exhaust leak, or from having the exhaust parts connected to metal hangers instead of hangers with rubber between the metal parts?