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> 1-in/2-out Muffler input needs alteration, Any advice ?
Literati914
post Aug 16 2024, 11:53 AM
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QUOTE(Shivers @ Aug 15 2024, 08:53 AM) *

Sorry but I have to ask, are you not defeating the reason for a header in the first place but choking it off at the muffler inlet pipe? Maybe you could knock a piece of wood into the inlet pipe and run a hole saw to get a bigger hole in the muffler and then weld in a pipe that is closer to the diameter of the header outlet? Just curious about the reduction


I think the pics are accentuating the pipe diameter differences more than the reality. I'm getting a consistent 54mm OD at the muffler-in, and throughout ALL of the stainless curved area... and 64mm OD at the muffler flange area AND the header flange are. So that's 2" and 2.5" ... is that an uncommon reduction? I've always heard a little backpressure was a good thing (IMG:style_emoticons/default/confused24.gif)

QUOTE(ChrisFoley @ Aug 15 2024, 01:38 PM) *

Actually, the inexpensive collector is far from optimized. The pipe going into the flange is way too big. Other than trying to make the reducer smoother, I don't think there's much to be gained by enlarging the muffler inlet.


Chris, can you elaborate on what you mean by "inexpensive collector" and how it could be optimized? I figure that comment was not necessarily a slight on the header unit, but I'm confused by the statement and would like clarity. I can change any/all of it .. and now's a good time for it. So if you have a suggestion, I'd like to hear so I can better consider how I handle it. I thought of scrapping the entire curved muffler pipe and starting over with ALL stainless, but honestly if it equals little to no gain, I don't see the point. Also, I was really trying to keep it simple and not buy a whole bottle of special gas for stainless as it's just a small job (was gonna get some Blue Demon self shielding stainless wire). All thoughts appreciated.
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Shivers
post Aug 16 2024, 02:33 PM
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QUOTE(Literati914 @ Aug 16 2024, 10:53 AM) *

QUOTE(Shivers @ Aug 15 2024, 08:53 AM) *

Sorry but I have to ask, are you not defeating the reason for a header in the first place but choking it off at the muffler inlet pipe? Maybe you could knock a piece of wood into the inlet pipe and run a hole saw to get a bigger hole in the muffler and then weld in a pipe that is closer to the diameter of the header outlet? Just curious about the reduction


I think the pics are accentuating the pipe diameter differences more than the reality. I'm getting a consistent 54mm OD at the muffler-in, and throughout ALL of the stainless curved area... and 64mm OD at the muffler flange area AND the header flange are. So that's 2" and 2.5" ... is that an uncommon reduction? I've always heard a little backpressure was a good thing (IMG:style_emoticons/default/confused24.gif)

QUOTE(ChrisFoley @ Aug 15 2024, 01:38 PM) *

Actually, the inexpensive collector is far from optimized. The pipe going into the flange is way too big. Other than trying to make the reducer smoother, I don't think there's much to be gained by enlarging the muffler inlet.


Chris, can you elaborate on what you mean by "inexpensive collector" and how it could be optimized? I figure that comment was not necessarily a slight on the header unit, but I'm confused by the statement and would like clarity. I can change any/all of it .. and now's a good time for it. So if you have a suggestion, I'd like to hear so I can better consider how I handle it. I thought of scrapping the entire curved muffler pipe and starting over with ALL stainless, but honestly if it equals little to no gain, I don't see the point. Also, I was really trying to keep it simple and not buy a whole bottle of special gas for stainless as it's just a small job (was gonna get some Blue Demon self shielding stainless wire). All thoughts appreciated.


If Chris says it's fine, I'm no expert. I'm thinking flow:

"The first question is at what cfm do we experience 120ft/s in 2" and 2.5" pipe? We calculate the area of the pipe, convert to sq.ft. & seconds to minutes, and after doing the math we find the answers are 157cfm for 2" pipe and 245cfm for 2.5" pipe (the Engineers will find both air flows at Mach 0.11)."

I had this in my head that loosed my fingers. Sorry (IMG:style_emoticons/default/confused24.gif)
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