Need to quiet the exhaust

[Alaskan_awd]

Can you please post any info you have on this 88db law you speak of ? I have heard nothing of it. 88db would indeed be difficult to reach, consider that an increase of 10db represents twice the sonic pressure, that would require an 80% percent reduction from the soon to be adopted 96db reg. Currently the test procedure is 18" perpendicular at 1/2 peak RPM, ie an M8 is measured at 4000 rpm.

Actually I believe 3bd is double, 10db is literally an increase of ten times.

Edit: Never mind I confused loudness with intensity. Although I think I am right in this case, from what I understand when you say 10db is double, that is what the human ear perceives as double and not an actual measurement. When measuring DB, a 3db increase/decrease is double.

 

[backcountryislife]

From That Bill:
25-12-110. Off-highway vehicles. (1) An off-highway vehicle operated within the state shall not emit more than the following level of sound when measured using SAE J1287:



(a) If manufactured before January 1, 1998. . . . . . . . . 99 db(A);



(b) If manufactured on or after January 1, 1998. . . . .96 db(A).



(2) A snowmobile shall not emit more than the following level of sound when measured using SAE J2567:



(a) If manufactured on or after July 1, 1972, and before July 2, 1975. . . . . . . . . .& #160;. . . . . . . . . . . . . . . . . . . . . ;. . . . . . . . . . . 0;. .90 db(A);



(b) If manufactured on or after July 2, 1975. . . . . . . . .88 db(A).



(3) (a) A person shall not sell or offer to sell a new off-highway vehicle that emits a level of sound in excess of that prohibited by subsection (1) of this section unless the off-highway vehicle complies with federal noise emission standards. A person shall not sell or offer to sell a new snowmobile that emits a level of sound in excess of that prohibited by subsection (2) of this section unless the snowmobile complies with federal noise emission standards.



(b) For the purposes of this section, a "new" snowmobile or off-highway vehicle means a snowmobile or off-highway vehicle that has not been transferred on a manufacturer's statement of origin and for which an ownership registration card has not been submitted by the original owner to the manufacturer.

OK, so it looks to me like LE agencies have a choice of two testing protocols?

The 96 being done at closer range than the 88?

Does that sound right?

 

[backcountryislife]

ttt

 

[hughesfoundation]

BD Muffler

Has anyone put one of BD's mufflers on a M7? Do you have advice? Pictures?

 

[JHG]

Has anyone put one of BD's mufflers on a M7? Do you have advice? Pictures?

It's an M8 not an M7 but the same concept. My only advice is be patient and use an air body saw and die grinder.

 

[hughesfoundation]

Thanks for the pics, if anyone has done this on a M7 please let me know how it went. The foot well on a M7 is diff from the 8. THKS AGAIN

 

[05snopro440]

OK, so it looks to me like LE agencies have a choice of two testing protocols?

The 96 being done at closer range than the 88?

Does that sound right?

That's not how it read to me. Seemed like 88 is for snowmobiles and 96 is for all other off-highway vehicles, with different tests used for each.

 

[hughesfoundation]

DynaFlow has a nice little 6 inch stainless muffler that worked on mine, I will snap a pic and post it up. It was about 120 bucks though !

Did you take some PICs?

 

[idareyou]

Does bd muffler set up have a place for an o2 sensor?