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. :-\
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.
And don't forget that a 8V71 would have two 4" exhaust pipes. 2.5 or 3" would be crazy.
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/
We have a pair of Stemco mufflers 3" really robust metal. I think they call it galvalume.
I think Flowmaster sells as versions of their two chamber race mufflers which are lighter with thinner metal
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
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.
THANKS For the response.Im looking hard at 2 flowmaster 50 delta flow. 8)
Have you considered Federally approved spark arresters instead of a second muffler? I suppose it would depend upon where exactly you want to go.
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