Exhaust operation and the back pressure myth "Or" Ask Uncle Otto about exhaust
03-11-2012, 02:53 PM
#33
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ok im having some power issues at low rpms with my 01 5.4. I have 1.75 longtube headers, 2.5 diamiter all the way back, y pipe, high flow cats, high flow cherrybomb extreme si/do. volant powerdane intake, uunder drive pullies and efans
from the line i feel like i have no power but at 10mph and i punch it i can chirp my 35's and i get thrown back in my seats.
Now from what i read here i have to much flow for scavaging at low rpms, can i throw on a dual chamber muffler to slow down the flow to help scavaging
from the line i feel like i have no power but at 10mph and i punch it i can chirp my 35's and i get thrown back in my seats.
Now from what i read here i have to much flow for scavaging at low rpms, can i throw on a dual chamber muffler to slow down the flow to help scavaging
03-11-2012, 02:56 PM
#34
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ok im having some power issues at low rpms with my 01 5.4. I have 1.75 longtube headers, 2.5 diamiter all the way back, y pipe, high flow cats, high flow cherrybomb extreme si/do. volant powerdane intake, uunder drive pullies and efans
from the line i feel like i have no power but at 10mph and i punch it i can chirp my 35's and i get thrown back in my seats.
Now from what i read here i have to much flow for scavaging at low rpms, can i throw on a dual chamber muffler to slow down the flow to help scavaging
from the line i feel like i have no power but at 10mph and i punch it i can chirp my 35's and i get thrown back in my seats.
Now from what i read here i have to much flow for scavaging at low rpms, can i throw on a dual chamber muffler to slow down the flow to help scavaging
03-11-2012, 10:28 PM
#36
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Thread Starter
I don't see a programmer on that list. Long tubes should be custom tuned for to ensure proper a/f. It's not an issue of too much flow, adding a chambered muffler will only make all throttle positions worse.
03-12-2012, 11:20 AM
#38
Those header primaries seem too big, especially for a truck. You have not "lost" your low end, it has just moved up the powerband.
Also, you want to stay away from, what I call the "logsplitter" and "swirlygig" gimmick mufflers, like Flowmaster, your cherrybomb, and Spintech. They are "Look at me, and hear the noise I am making" mufflers, and are about as useful as an 8" diameter exhaust tip.
You dont want any restrictions in the flow path.
Straight through mufflers like the Dynomax Superflo and Magnaflow mufflers, and the orginal Cherry Bomb Glasspack mufflers are Ideal.
You MIGHT be able to pick up some low end by installing a muffler of straight through design, but for truck headers, I wouldnt go any bigger than maybe 1 1/2".
If you dont want to mess with the exhaust, the only thing that I could really think of is to go lower with your rear end gearing.
Also, you want to stay away from, what I call the "logsplitter" and "swirlygig" gimmick mufflers, like Flowmaster, your cherrybomb, and Spintech. They are "Look at me, and hear the noise I am making" mufflers, and are about as useful as an 8" diameter exhaust tip.
You dont want any restrictions in the flow path.
Straight through mufflers like the Dynomax Superflo and Magnaflow mufflers, and the orginal Cherry Bomb Glasspack mufflers are Ideal.
You MIGHT be able to pick up some low end by installing a muffler of straight through design, but for truck headers, I wouldnt go any bigger than maybe 1 1/2".
If you dont want to mess with the exhaust, the only thing that I could really think of is to go lower with your rear end gearing.
03-12-2012, 01:33 PM
#39
Put in oversize Stainless muffler with dual outlets, add turn ups and 6" polished stainless stacks out the front of the bed next to the cab. Drill a 3/16" weep hole in the bottom of the turn up in case of rain. Rumble on dude, LOL.
Last edited by papa tiger; 03-12-2012 at 01:38 PM.
03-28-2012, 10:08 PM
#40
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back pressure
I have used this site for information for a while now, but this is my first post. I just put on a levelling kit, 295/70R18 Nitto trail grapplers, and did the gotts mod. Im now looking at exhaust, and plan on getting an edge programmer sometime in the future also. I have read on other threads that keeping back pressure, or creating more helps with take off if you have bigger tires. The local exhaust shop suggested that I do a catback SI/DO with flowmaster 40 series, with 3'' pipe from the stock Y pipe to the muffler then 2.5'' exiting to the back and not true duals because I would loose back pressure and get no big gains compared to the SI/DO... Would this be a good set up? Im not really looking for big HP or MPG gain, but mostly to offset the effects of the larger tires. (want it to sound good too) Sorry if some of this has already been answered in the original information, some of that went over my head!
Thanks!
Thanks!