glass packs

[biff]

You guys running glass packs do you like them?and how much more noise is it in the bus? and are you using 3 inch or 2.5 inch bore?I want to put them on a mc8 8v71n.

[chessie4905]

We dont use glas packs. The padding will eventually deteoriate making it equivalent to straight through. Pluss the normal diesel soot accumulation will plug the holes to the packing . Generally resonators are used, if owner doesnt mind any additional noise generated.

[DoubleEagle]

And don't forget that a 8V71 would have two 4" exhaust pipes. 2.5 or 3" would be crazy.

[chessie4905]

Flowmaster makes some nice compact mufflers in one, two, and three chamber in 3 and 4 inch inlet and outlets. I used a 4 inch on a 6.2 diesel truck several years ago. Sweet sound. Their mufflers are made of substantial sheet steel, not the thin stuff used in traditional automotive mufflers.

https://www.holley.com/brands/flowmaster/products/exhaust/mufflers/street_chambered_mufflers/

[dtcerrato]

We have a pair of Stemco mufflers 3" really robust metal. I think they call it galvalume.

[chessie4905]

I think Flowmaster sells as versions of their two chamber race mufflers which are lighter with thinner metal

[TomC]

Donaldson makes a really nice oval muffler with 5" in and out at the same end (M120131). It is rated for turbo engine, but will work on any. Puts out a nice tone, and is free flowing. Good Luck, TomC

[Ed Hackenbruch]

 Don't remember the number but they also make one with 5" on each end.  I wanted to be able to put my tailpipe coming out on the side just behind the tire so that i could see it in my mirror.

[biff]

THANKS For the response.Im looking hard at 2 flowmaster 50 delta flow.

[HB of CJ]

Have you considered Federally approved spark arresters instead of a second muffler?  I suppose it would depend upon where exactly you want to go.

[Jim Eh.]

I have compiled a list of mufflers to use on (mostly) NA DD engines for bus application.
Not a complete list but follows the published mufflers for a DD NA engine with a few "aftermarket" alternatives. (The D13-1023 listed at the bottom is a Shuttleworth product, Canadian).

This list does not include any glass packs as I feel they are only a short term use item.

If you wish to select a Donaldson (or other brand) please google a crossover part#. Keep in mind some (or any) of these mufflers may be used on a turbo engine with varying results. A turbo'd engine requires even less sound attenuation so select accordingly. I make NO promises as to your choice from using this list to result in your desired result, just as a guide as to what is available. If there is no db rating or restriction info, it was not published for use nor tested with a DD 2 stroke engine. I made this list in a frame but the forums do not express the format correctly(7 columns).

NELSON MUFFLER #s             LIST FOR N.A. MOTORS  (X OVER LISTS FOUND ONLINE)

(STYLE 1 = END IN ON C / OTHER END OUT ON C)  (STYLE 2 = END IN OFFSET / OTHER END IN OFFSET)(STYLE 3 = END IN / SAME END OUT) (STYLE 4 END IN ON C / OTHER END OUT OFFSET)

(NOISE IN DECIBELS @ 50 FEET)(DIMENSIONS IN INCHES)(RESTRICTION IN "of HG @ ENGINE )
PART #   STYLE   OUTLETS   BODY SIZE   O.A.L.   NOISE   RESTRICTION
6-71 NA   SINGLE MUFFLER               
86115M   3   4.0 – 4.0   10X15 OVAL   26   79   3.7
                  
6V-71 NA   SINGLE MUFFLER               
86125M   2   4.0 – 4.0   10X15 OVAL   26   83   1.8
86543M   2   4.0 – 5.0   10X15 OVAL   27   82   2.3
                  
6V-71 NA   DUAL MUFFLERS               
86159M   2   3.0-3.0   8.3X11.5 OVAL   26   81   3.0
86512M   2   3.50-4.0   8.3X11.5 OVAL   28   82   1.2
86106M   2   3.50 – 3.50   8.3X11.5 OVAL   26   83   1.9
                  
8V-71 NA   DUAL MUFFLERS               
86512M   2   3.5 – 4.0   8.3X11.5 OVAL      83   1.8

Other mufflers (to fit) but NOT rated for DD 2 STROKE

86560M   1   4.0 – 4.0   8.9 RND   20
D13-0123   1   5.0 – 5.0   8.9 RND   23
86121M   3   5.0 – 5.0   10X15 OVAL   26
            
86144M *   1   4.0 – 4.0   9.0 RND   11.5
86145M *   1   5.0 – 5.0   9.0 RND   11.5
            

* = RESONATORS