545 any members try to bypass the secondary muffler?
#1
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My Ride: 545I and a half dozen other rides
I'm still green so please bear with me.
I notice on my 545i there are two mufflers with the tips. One muffler outlet has a valve on it before the tip. At idle it is not open.
Does it open only in low vacuum (wide open throttle)?
If so has anyone put just a straight pipe in there (in place of the muffler but leaving valve intact and working) to see what happens?
I'm hoping it would have a nice stock sound to it until wide open throttle.
I notice on my 545i there are two mufflers with the tips. One muffler outlet has a valve on it before the tip. At idle it is not open.
Does it open only in low vacuum (wide open throttle)?
If so has anyone put just a straight pipe in there (in place of the muffler but leaving valve intact and working) to see what happens?
I'm hoping it would have a nice stock sound to it until wide open throttle.
#2
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Location: Colorado USA
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My Ride: 2004 545i, 6-speed Manual, Silver Grey Metallic, Grey Dakota Leather, Cold Weather Pkg, Premium Sound Pkg, Sport Pkg, Lumbar Support
I believe it opens based on RPM, not throttle. In the lower gears, i.e., lower road noise, I believe I can hear the second path open up around 3,500 RPM. There is also a noticed boost in thrust. Since we have continuously variable valve timing, I do not believe this is related to a different valve timing program, but the exhaust.
#3
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My Ride: 2004 545i - 2001 325i
I went ahead and removed everything the two mufflers it has and installed one free flow exhaust with double tip and man i can tell you my car sounds incredible you can barely hear it from the inside of the car but the engine of the 545i sound really nice and deep. I did not noticed any lack of power and on high speeds feels even better.
I hope this helps
Luis
I hope this helps
Luis
#4
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My Ride: 545I and a half dozen other rides
I went ahead and removed everything the two mufflers it has and installed one free flow exhaust with double tip and man i can tell you my car sounds incredible you can barely hear it from the inside of the car but the engine of the 545i sound really nice and deep. I did not noticed any lack of power and on high speeds feels even better.
I hope this helps
Luis
I hope this helps
Luis
I want the secondary bypass to open up during wide open and quick squirts.
Allen
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My Ride: 05 545i
You can do a bypass mod to keep both mufflers in play....go to autozone and get a universal vacuum line connector...open trunk...remove left side cover.....next to tail light there is a solenoid that has two vacuum lines connected to it....unplug both from solenoid and connect directly inline to universal connector....this will keep both mufflers in play at all times....called the golf tee mod for the 3 series
I have not noticed a change in exhaust sound...throttle response is a little better
I have not noticed a change in exhaust sound...throttle response is a little better
#6
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Unless other modifications are done to the engine, playing with the exhaust system will only result inmodifying the sound and possibly reducing power.
Salut, Bob P.
#7
You can do a bypass mod to keep both mufflers in play....go to autozone and get a universal vacuum line connector...open trunk...remove left side cover.....next to tail light there is a solenoid that has two vacuum lines connected to it....unplug both from solenoid and connect directly inline to universal connector....this will keep both mufflers in play at all times....called the golf tee mod for the 3 series
I have not noticed a change in exhaust sound...throttle response is a little better
I have not noticed a change in exhaust sound...throttle response is a little better
To the OP, just get a nice exhaust system and drive in a reserved manner with people in the car. popping the valve open all the time doesn't make that big a difference. If it's a nice system people will like the sound anyway.
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