11-29-2012, 10:39 AM | #1 |
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3.5 exhaust observation
Is it just me or anyone else happen to notice 90% of exhaust comes from the driver side pipe, little to none from passenger side.
I initially didnt notice this much during the summer but now winter time its quite easy to tell by the fumes and even the sound puring from the tips the right side is kinda idle with hardly anything going on. just me or take it in for investigation? Thanks guys! |
11-29-2012, 01:11 PM | #3 |
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Might be the same set up as my 335 coupe. There is an exhaust valve that opens the passenger side muffler after like 3-4K rpm's. There is a wire you can unplug in the 335 that opens the valve up and gives you a nice rumble echaust tone. Have not had any issues with it, not sure if they have that on the X6. Look into the Golf Tee mod
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11-29-2012, 09:58 PM | #4 |
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It is same as 335. My wife's X6 35 did this also, looked silly in winter when idling.
One pipe is "tuned" to sound aggressive, this is the one that's closed on idle - a flapper is actuated under certain RPM ranges opening the exhaust. I'm sure there's probably a technical reason for this as well (back pressure?). I used the golf tee mod. You should be able to query it on post - essentially just a hose clamp. Was a pain to install, but possible with basic tools (screwdriver) and no lift (you can reach it under rear of car). Sounds awesome once you open it - even more aggressive than my X6 50 when warming up. It's almost loud enough it annoys my wife, but it gets quieter once engine warms up (but still sounds very aggressive). Great mod - simple install and very cheap. |
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11-29-2012, 11:19 PM | #5 |
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This is a real mystery in terms of the 3.5 and 5.0. I believe the 35 leaves the 2nd exhaust closed most of the time - including startup. Whereas the 50 has both open on startup and then closes one down. SOME have said that they noticed reduced power with the golf tee mod. Some have suggested that the entire reason for closing one exhaust is to warm up the catalytic converter faster - which would make sense I guess. Either way, there is a vacuum actuator on the exhausts that open them up.
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11-29-2012, 11:27 PM | #6 |
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+1 Doug. Yep according to a friend whose a BMW Mechanic, it is mostly to curb noise pollution and also does warm the cats during cold start sequence.
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12-05-2012, 07:18 AM | #8 |
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Great post! I have a 50i and while I like the sound (under acceleration) I wouldn't mind a little more agressive exhaust note. I've done a search but can't find anything specific to "golf tee mod".
Anyone know where I can find instructions for implementing the golf tee mod? |
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12-05-2012, 08:44 AM | #9 | |
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Quote:
http://forums.bimmerforums.com/forum....php?t=1449107 http://www.e90post.com/forums/showthread.php?t=78447
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