Muffler Choice-Towing, low noise, reasonable flow?

[GGibson]

I'm looking for a combination that will give low noise with reasonable flow. Currently have '96 stock exhaust system but would like to help air flow without giving up too much on the noise. I will also give up CAT. I've heard of guys using two Walkers in Series, Some using Resonator followed by a long Donaldson. What say you guys?? Not going over 300HP so I've heard I don't necessarily need a 4".

 

[Diesel Gunner]

I would suggest just cutting off the muffler and straight pipe it from there. I left my resonator on and it is not too loud. Dropped EGT about 100-150* and only cost me $60. 00.

 

[markdixon]

I used a muffler from auto jet very well built 4in inlet and outlet. I removed the cat also I was concerned with the noise issue also this muffler is only slightly louder than stock. If I were reinstalling it today I would inverse it to make it a bit louder. It's a cambered muffler design with only basically two pieces of pipe on both ends with what resembles a cheese grader effect done to them in one direction. muffler

 

[Steve Campbell]

I bought a NAPA muffler.....

similar in design (straight through, but the cheese grater part is only holes with nothing sticking out into the exhaust stream) to the one markdixon describes. It was only 3 1/2" I. D. both ends. Approx 30" long. It made the exhaust note a "deeper" tone but no louder unless under heavy load. Crusing, it is not any more noticeable than the stock muffler. I also left the resonator on the truck. I gained 1-1 1/2 lbs of boost by going this route.



It is slightly..... louder when under heavy throttle though. I am very comfortable with it. I do not like a LOUD truck, but I can live with this.

 

[Mtngoat]

Question

With no muffler, I know it sounds awesome going down the street, but is it much louder inside??

 

[Cooker]

I have a new Walker 21468 muffler that am looking to sell. Joe Donnelly has recommended this muffler many times before. It has a 3" inlet and outlet and makes a great free flowing replacement for the stock muffler. PM me if you are interested.

 

[baby.driver]

You could listen to my DD 4in.

But if you don't want to change your sound, why change?

You got high EGTs or something?

 

[Hillbilly Hotrodder]

Mtngoat

Mtngoat



I had my muffler "fall off" at the local shop last week. It cost me $35 total. Trust me, I'm a picky SOB, and I love it. I have a 10 day old daughter and I was scared that it would be too loud on her ears. Believe me, if you stay below 1/2 throttle, you can't tell anything has been done to it. My wife has been riding in it all week and hasn't noticed any change either. When you really boost it up, you can hear it, but only with the window down. If both windows are up, no more noise than stock. Just leave the resonator in place. You will not be sorry.

 

[WKener]

I have the Walker muffler that Cooker mentioned, 3" in/out (also listed as a Dynomax) as well as a missing cat and you can't tell the difference in sound from within the cab. If you drive next to concrete barriers and hammer it, you can DEFINITELY hear it, but under normal driving circumstances it is barely audible. I highly recommend it.

Wes

 

[GGibson]

Thanks you guys re. the Walker offer. I'm towing a lot and have some power off and on all day in rolling hills. I'm looking for something quieter if possible. I'll keep exploring. Again, thanks for the great offer, maybe someone else will pick up it up.

 

[TBOB]

DONALDSON

TRY TO GET A USED MUFFLER AT A LARGE TRUCK BONE YARD. THEY ARE USUALLY CHEAP WITH SOME PIPE ATTACHED. THEY FLOW WELL AND DO NOT INCREASE NOISE. TBOB

 

[HBarlow]

Does the NAPA/Dynomax muffler provide any reduction in EGT?



Harvey

 

[SWC]

I was in the Vancouver BC area recently and stopped in at PDR. I had a problem with not getting over 26 lbs on the boost gauge and I had to keep an eye on the pyro. All I have is an EZ and I thought I should be in the 30 lb range. Al said they had a special on the Pinnacle 4" exhaust. I said put it on.

Now I can make 30 psi and the EGT does not get over 1150 degrees. I suppose I could have straight piped the stock system but I have heard a few of these and did not like the sound. The stock exhaust in my truck was choking off the flow of the air leaving the motor.

Maybe we don't need a four inch if under we are under 350 hp but I would bet that a lot of the stock exhausts are not nearly as free flowing as an after market system designed for our trucks.

Stan

 

[gitchesum]

Funny you should mention mufflers.



After running straight-piped for almost 2 years, I decided to change my exhaust up a little.

I added the Walker muffler, but at the same time, I configured the exhuast to exit just forward of the rear tires. I figured the muffler would just cancel out the noise of the shorter exhaust pipe.

Boy was I wrong. It has a great tone without having the annoying drone at 2000RPM's I had with the straight pipe. I did notice that I can't hear the rumble as much as I used to but the turbo whine is much more pronounced. Not a bad thing at all.



The strange thing was the drop in EGT's. With the straight pipe, I could floor it at 70 and before I hit 80, the EGT's were at 1500*. Now i can get up to 95 before the EGT's are in the "Whoa Zone"



Not sure if it's the shorter pipe, taking out 3 bends, or replacing a section of pipe that went from 3" to 4" back to 3" in a matter of 12". Either way, I'm happy.



BTW, thanks to Bill Lins for the donated muffler. How's that 4" sound after a couple of weeks Bill?

 

[GiesJ]

GGibson - I don't know if you meant you were going to remove the cat, but if you are and CA is a state like Colorado, you might need to keep it to pass vehicle inspections. I know that they have a vehicle checklist per year and if it came from the factory with a CAT you need one for the inspection. Pretty silly but something to think about.

 

[rich m]

Originally posted by gitchesum

Funny you should mention mufflers.



After running straight-piped for almost 2 years, I decided to change my exhaust up a little.

I added the Walker muffler, but at the same time, I configured the exhuast to exit just forward of the rear tires. I figured the muffler would just cancel out the noise of the shorter exhaust pipe.

Boy was I wrong. It has a great tone without having the annoying drone at 2000RPM's I had with the straight pipe. I did notice that I can't hear the rumble as much as I used to but the turbo whine is much more pronounced. Not a bad thing at all.



The strange thing was the drop in EGT's. With the straight pipe, I could floor it at 70 and before I hit 80, the EGT's were at 1500*. Now i can get up to 95 before the EGT's are in the "Whoa Zone"



Not sure if it's the shorter pipe, taking out 3 bends, or replacing a section of pipe that went from 3" to 4" back to 3" in a matter of 12". Either way, I'm happy.



BTW, thanks to Bill Lins for the donated muffler. How's that 4" sound after a couple of weeks Bill?

Heee-heee-heee!!

I was straight-piped (4")and forward of rr tire for about 2-3 years, also, and just had one of Rip Rook's 4x30 "cherry bombs" installed on Friday... . mellowed out the metallic echo a lot and deepened the tone a little, Still sounds very HD, but without some of the annoying subliminals that were there before... also, seems to have eliminated a cab-drone that I would get under some conditions... (still got essentially the same exhaust, 4" short system w/ only a single 45* turn after the down-pipe, exiting in front of rr tire)





as for the egt change, it's probably due to the shorter system, with fewer bends. you may also be getting a little bit better slip-stream scavenging than previous... HP difference: real world, maybe 2HP... if it's a Chevy it's good for at least 197HP!!(without decals)