New exhaust thought and question

[tourus]

OK I need a new exhaust on my truck... 85 M1010 . I have a new stainless steel muffler that I bought a few years ago never used. It is 3" in and 3" out.. about 10" round and about 36" long. it was for a 350 with headers and y pipe that never got used.

so my idea is to make a y pipe 2 - 2 1/4 welded onto a 3" inch pipe then into the muffler and then all three inch out the rest of the way.

I am looking for input and ideas on weather it would be to much back pressure or not or work it not be enough flow .

 

[cucvrus]

My thought? Not proven. Plumbers theory. You have 2 1/4" - 2 1/2" header manifold pipes now trying to make their way thru a 3" opening. Roughly 5" of exhaust flow being forced into 3". Enough said? Don't design the exhaust system from the muffler front. You must design from front to back. Same thing I was taught. You enlarge the further you go back not make smaller. IMHO. It is fine withme if you don't agree. Its your truck and I am not an engineer in any shape or form. Just a novice. Have a great day.

 

[Ilikemtb999]

Why not buy a second muffler?

 

[MarcusOReallyus]

The cross sectional area of a 2 1/4" pipe is 3.976 square inches. You have two, so that's doubled, to 7.952 sq. in.

A 3" pipe has a cross sectional area of 7.069 sq.in.

That means you'd be losing almost a full square inch.

Probably not a good plan. Listen to cucvrus. He's got it nailed.