Dummy tailpipe?

WHL102 · 12-01-2015, 11:38 AM

I was driving behind an otherwise normal 528xi when I noticed something strange about the exhaust tips. The one on the right looks like it goes nowhere! I can't imagine it was modded from a single tip to dual tips as the driver was an older lady, IIRC.

ndinh · 12-01-2015, 12:28 PM

Nope. All 528's have these. The inside opening has a flap that opens at higher speeds and closes to increase back pressure at normal speeds. I don't have a 550 but I believe the 550's have flaps to cover the inside openings on both sides as well. Someone with a 550 can probably chime in.

WHL102 · 12-01-2015, 12:47 PM

Quote:

Originally Posted by ndinh

Nope. All 528's have these. The inside opening has a flap that opens at higher speeds and closes to increase back pressure at normal speeds. I don't have a 550 but I believe the 550's have flaps to cover the inside openings on both sides as well. Someone with a 550 can probably chime in.

Very interesting - I've heard about the flap but I never realized it would be so visible!

peter91118 · 12-01-2015, 03:57 PM

Quote:

Originally Posted by ndinh

I don't have a 550 but I believe the 550's have flaps to cover the inside openings on both sides as well. Someone with a 550 can probably chime in.

Yup

BBLF13 · 12-12-2015, 07:59 PM

yeah those are the flaps. my 650 has those flaps as well

Bmw doubles · 12-14-2015, 10:23 PM

They rattle as they get older. Eventually you just do a golf tee mod or on the jb4 you can program a setting for flap always open.

Ace333 · 12-19-2015, 07:58 PM

I am in the exhaust industry here in USA. These are active valves used for tuning and back pressure. Very common in cars these days. Especially higher end models.

12-01-2015, 11:38 AM	#1
WHL102 First Lieutenant 125 Rep 391 Posts Drives: '16 GTI S, DSG, 4-Door Join Date: Jan 2014 Location: Northern NJ iTrader: (0)	Dummy tailpipe? I was driving behind an otherwise normal 528xi when I noticed something strange about the exhaust tips. The one on the right looks like it goes nowhere! I can't imagine it was modded from a single tip to dual tips as the driver was an older lady, IIRC.
	Appreciate 0 Tweet Quote

12-01-2015, 12:28 PM	#2
ndinh Lieutenant 161 Rep 554 Posts Drives: 640i GC, X5 Join Date: Jul 2015 Location: Los Angeles iTrader: (2)	Nope. All 528's have these. The inside opening has a flap that opens at higher speeds and closes to increase back pressure at normal speeds. I don't have a 550 but I believe the 550's have flaps to cover the inside openings on both sides as well. Someone with a 550 can probably chime in.
	Appreciate 0 Quote

12-12-2015, 07:59 PM	#5
BBLF13 BMW Enthusiast 7 Rep 71 Posts Drives: 14' 650i Coupe Join Date: Aug 2012 Location: West Los Angeles, CA iTrader: (0)	yeah those are the flaps. my 650 has those flaps as well __________________ 14' 650i Coupe. Alpine White M-Sport Package Dinan Stage 1 H&R Lowering Kit
	Appreciate 0 Quote

12-14-2015, 10:23 PM	#6
Bmw doubles Dream crusher 984 Rep 2,421 Posts Drives: Fast Join Date: Mar 2015 Location: westside iTrader: (0) Garage List 2011 535 [0.00]	They rattle as they get older. Eventually you just do a golf tee mod or on the jb4 you can program a setting for flap always open. __________________ 535i MIssion Performance, PS2, Helix HPFP Kit, Wagner FMIC, Spec 3 clutch, Steel SMF, Wolf Racing CP, UUC SSK, GFB dv, SprintBooster, Custom Dynomax Exhaust, M5 Sways, Eibach OE Springs, Koni Sports Adjustable, Custom Short Ram CAI IG: @bmwdoubles
	Appreciate 0 Quote

12-19-2015, 07:58 PM	#7
Ace333 New Member 2 Rep 27 Posts Drives: 2012 535XI Join Date: Apr 2012 Location: Detroit, MI iTrader: (0) Garage List 2008 528XI [0.00]	I am in the exhaust industry here in USA. These are active valves used for tuning and back pressure. Very common in cars these days. Especially higher end models.
	Appreciate 0 Quote