I am finding all of the information on mufflers confusing and exhausting. What are the drawbacks to using adapters from 4 inch exhaust to 5 inch mufflers? I am looking at Donaldson M120474 with 5 inch inlet and outlet, length 34 inches, 1762 cfm @ 1 inch Hg backpressure, 2450 cfm @ 2 inch Hg backpressure, good noise attenuation 12-18 dba. I realize by choking the outlet to 4 inch the flow rates are reduced but figure it would be comparable to the M090544 in a shorter package. The 4 inch pipe to 5 inch inlet should have no adverse affects on the flow rates of the muffler.

sittin' in the sahara desert waiting to go home!
L8r,.........dogger

 

hah. exhausting

should be no problem doing this. As I think about it, the flow numbers are all way overkill, so you won't (in my opinion) see any flow or EGT difference in going to a 5/5 muff. The only diference will probably be sound. the muff might act like an expansion chamber and a muff at the same time -- owing to the sudden increase of 4" pipe to 5" pipe, and then the opposite at the other end.

BTW, "choking the outlet to 4" does not change the flow specs of the muff. the muff is rated by itself and whatever pipes you hook up carry their own restriction.

 

Hey Dogger, did you change your exhaust?

 

I am not finding a Donaldson M120474?? but the flow and dba numbers posted above sure look good on paper anyway.

 

Matt,

Never got around to it due to financial constraints. As you say looks good on paper.

L8r,.....dogger