Quiet 4" muffler?

["Mad Max"]

Folks,



I've now got two 6BT-powered rigs (the tugboat '93, and the '78 Ramcharger trail rig), and I just got a muffler from the local Kenworth dealer for the tugboat. It is 45" long, and appears to be just right.



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Look inside -



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This muffler is from a company called ACRAFIT, and it has a wall dead center within it that forces the exhaust (and sound) to go through the perforations verse just straight through. I cannot help but believe this will be great for noise cancellation. Has anyone else seen such a muffler, and if so do you like the noise level, and did you notice a performance difference?

I figure the longer the muffler is the better it will perform, right?... more surface area = more perforations for cross-flow = less restriction in flow... and an increase in performance potential, ja?

I have heard of the Donaldson line but I cannot get any info on what it looks like on the inside and/or how it 'sounds'.



Now, I'm wanting to install a similar muffler on the Ramcharger, which has a lot less wheelbase to work with, so I'm looking for a similar muffler... but is about 2-3 feet long. I may be able to get this 45" monster to fit in the RC's chassis, and if so, bonus. This muffler was $75 bucks at my local KW shop - not a bad price, and I'll be happy to get another one just like it for the RC unless I can find one a bit shorter.



Anyone?



Mucho thanks,

- Sam

 

[OKish]

looks like that would just be hell for flow. i don't know how i would like that. But if you are going for quiet it would be great.

 

[JGrefenstette]

as far as a good quiet sound and great flow, i help a co-worker put an MBRP cat back muffler/exhaust system on our bosses '04. i dont know if they make them for the 1st gens, but i bet you could get one to work. they offer great flow and a very nice sound, silent in the cab for the most part, and a good soft tone if behind the truck. but hey, these old 12valves love to be straite piped so their voice can be heard. let that baby sing and put a 45" piece of strait pipe instead!! :-laf

 

[cerberusiam]

Muffler!!!! Thats a bloody surpus afterburner!!





Looking for a little rocket assist on takeoff??? :-laf





I personally like the Borla mufflers. Small, good flow, good noise control. A little expensive is the only downside.

 

[Paychk]

www.peterbilt.com/parts/pb/includes/catalogs/Acrafit_Exhaust.pdf

 

[JLEONARD]

I have a 4 inch Allied muffler on my rig... it about 36 m " ling. From memory I think it was built similar the the one in the pic... it IS quiet.

 

[Jgolden]

This is the parts number on my bill for a 4" in and out Donaldson muffler.

M110189, I think it is the manuf number. Donaldson has a pretty detailed web site, if you want to study up. They list back pressure and flow numbers.

They have a number of 4" mufflers. It is not a DOC (Diesel Ocy Catalyst) model. Web shows that version with that number also plus DOC.



This one measures approx 40" long, 12" diameter. This is on a front engined motorhome, so i have lots of room. I think it was $160

I put this one on because the straight pipe, which did lower egt and increase power over the stock muffler was way too loud.

The original muffler that I removed was a lot smaller and had a full baffle that must have been pretty restrictive. I didn't see any change in numbers, increase in egt etc. over the straight pipe but the Donaldson was way quieter.

 

[Mopar_Tim]

i have got a donalson just like you were looking for ... . looks almost identical to the pics you posted







good luck fitting a muffler on the rc ... . i could not get one to fit at all on my 79 ... now i did not try too hard b/c i used a prebent kit for a 1st gen and modified it to fit ... ... and the way it runs the muffler simply does not fit

 

[puff1]

sleeper

I just installed a 4" ss from stans and the inside looked exactly the same. I thought it would sound like the muffler on my 4" ss kit that I put in my 2001, but it is so quite. In my 2001 I used to punch it when going under a bridge and hear an awsome rumble. With the kit on my 93 I hear nothing. The neighbours like it though. Like the guy before said it was a donaldson flo-through. It's the way to go if you want quiet performance, and I noticed that I drive alot faster and harder when I'm not worried about blowing peoples windows out. Hope this helps.

 

[Mopar_Tim]

the kit i used was a stans so i have got the same muffler sitting around taking up space in my grandmothers barn