My truck don't have muffler or resinator on it,just a straight pipe,but after 3 years I am getting tired of the noise,what would be the best way to quiet it down with keeping the EGTs down.I was thinking of putting the muffler back on because I cannot afford a new exhaust system right know,but am worried about high EGTs.<br><br>Any advise would be helpful..Thanks

 

You shouldn't have a problem unless you are running a fueling<br>box of some kind. just my opinion. ???

 

Get a straight thru muffler. Like a Bullet from Dynomax except larger and with more insulation.

 

There are ways to make the engine more quiet. Look for a member name Greg(aka The Noise ****), don't rememebr his posting name at the moment. He has tried lots of things, and has a great truck. <br><br>If you try a search, just try Noise ****, and he should come up in the &quot;subject&quot; feild.<br><br>Andrew

 

I'll have to try searching for noise **** myself. probably some good info there. I remember a noise discussion here some time ago, with respect to the exhaust, and there's been some other discussions about exterior noise in general as well. Basically, there two major sources of exterior noise:<br><br>1. engine block. the valve cover and oil pan can be covered, and hood liner can be installed, to reduced exterior noise. I understand that some who have done this are actually able to drive through fast food drive-throughs without shutting down. <br><br>2. exhaust. This one is interesting, with regards to sound waves coming from the tailpipe. There are some arguments relating to the physics of acoustics suggestting that not only is the location of the resonator important, but that two could be very effective. A straight through resonator is pretty simple -- usually just a sudden increase in pipe diameter perhaps lined with a screen. Its the sudden diameter change that causes sound waves to reflect -- hence the suggestion that putting in a resonator near the end of the tailpipe would reflect lower frequency sound energy back up towards the engine. Diesel Dynamics also has reported success with a 4&quot; exhaust system that is just as quiet as the stock system. guess what: it uses two resonators.<br><br>some sort of resonator system is the only way to reduce the intensity of sound coming out the tailpipe (that is, covering the pipe won't help). the dual - resonator seems to have promise in my opinion. Anyone tried that?

 

Yes I started looking for that name in the search engine,but came up empty.<br>I know if I put the muffler back on it will heat up quick with the VA on there..

 

[quote author=Old Iron link=board=4;threadid=14545;start=0#136961 date=1052658947]<br>Had my truck straight piped also ,it was ok unless I was pulling with the camper on around 2200 rpm got really loud, I just put a singal Flow Master 3&quot; on where the resignator was it sounds great a nice low sound at lower rpm and quiter at highway speed. Good Luck . <br>[/quote]<br><br>I think I will give that a shot..Thanks guys

 

remember though, flowmaster isn't the way to go for performance (baffles). a 4&quot; flow-through muffler is very quiet when not installed in a 4&quot; exhaust. i have a 4&quot; flow through magnaflow (24&quot; worth of packing) with a reducer back to the stock tailpipe. before the gutted cat had a pipe in there- i couldn't hear a thing. the pipe added a little in terms of noise as the shell wasn't acting like a resonator anymore, however, i still couldn't hear it unless i was standing outside while someone drove my truck. now only 4&quot; lengthwise of packing is doing any work so hence it's almost straight piped.

Tom

 

[quote author=Pavonis link=board=4;threadid=14545;start=0#136821 date=1052593048]<br>Regarding sound insulation blankets and covers on the engine, here's a recent post on the Open Roads Forum:<br><br>&quot;... My experience when towing a 7K load: coolant temps up 10*F, engine oil temps up 30*F, and EGT's up an average of 100*F.&quot;<br>[/quote]<br>for just a valve cover and an oil pan cover? I'd like to know what all this guy was covering. there are products out there that cover the entire turbocharger and the first 2 feet of the exhaust pipe too, and I'm not advocating that. I can see the oil pan might contribute some cooling, but its hard to imagine that the valve cover would. <br><br><br><br><br>I'm not sure I agree with that conclusion. DC may still have been learning about the noise issue from a marketing standpoint, but for the most part noise was a don't care. That is, I don't think they were motivated in the noise department until 03. witness the removal of the hood liner...<br><br>certainly, there are more elegant ways to reduce noise besides sound insulation in the engine compartment, and from a marketing standpoint I can't imagine putting anything over an otherwise nice looking valve cover. And an oil pan cover presents a maintenance and convinience thing. So really, DC doesn't need a performance ramification to keep those things off. When you're the manufacturer, you can build in sound reducing things into the design and make them elegant -- like more insulation on the firewall, seat pan, perhaps put the hood liner back (did they do that in 03?). Of course the big deal noise wise for the 03's is the common rail design, which itself is the major contributor. didn't they change the exhaust system as well for 03? not sure about that. <br><br>Anyway, my point is that for the pre-03 trucks, noise was a don't care, and after market tricks are necessary to quiet things down. It would be great to get more data on the reported temp increases, especially if there was any covers used besides one on the valve cover, a hood liner, and an oil pan cover. I doubt, for example, that DC took the hood liner out to improve cooling ;D<br><br>As I say, the oil pan might be a very minor contributor, but considering the surface area and heat radiation capacity of the exposed pan, I'm not sure that would be significant. Also, there are many many factors to consider before generalizing that temps increased due to a cover. However, I don't want to assume that this was a poor experiment: if two runs were made during identical outside temps, with the same cloud cover, up the same grade, with identical pulling conditions, at the same speed, one pull with a valve cover blanket and one pull without, then I'm on the edge of my seat. My point is that, lacking additional detail (which may exist an just not provided), environmental factors and pulling conditions go along way to explain the results. <br>

 

Best thing you can do is put a muffler on it and use some sound deadening material. Look at www.b-quiet.com and get some brownbread. Get a hood liner if not equipped and then brownbread the hood then install the liner. Strip the interoir of the truck and brown bread everything. This is my setup its pretty cheap and extremely effective on road noise.

 

Give Rip Rook a call - and get his 5&quot; system.. Straight thru design and quiet also...<br><br>http://www.protintnw.com/sa_dodge-exh.htm<br><br>

 

Theres a lot of noise coming from the factory timing.
Theres also a great deal of noise coming from the VP-44 injector pump.
In addition, the resonance of certain metallic areas of the engine really are hard to pin down as they travel through the driveline and cab.
One area is actually the oil pan...its like a large steel drum.

I bet if one was to address the VP-44 noise, timing and the oil pan...there might be some ;D ;D ;D

The Edge EZ will help the timing.
An insulated cover on the VP-44 area will help and more ABS for a shield over the pan about 3/8&quot; away from the steel will damp the sound.

The hood is simply a reflective surface...big drum. Adding an insulation mat might 'reduce' audible noise but the resonance will still travel.

 

Scotty,<br><br><br> Do you have more info on this ez timing and pump cover I can look into. <br><br><br>Thanks <br>Dave

 

One way that Chevy quieted down the Duramax was to go with an extremely thick Bellhousing on the standard and a thick trannycase on the Allison. They sited that alot of the noise from the engine came from the back of the crank area.<br><br>I read that somewhere ???