Dual Exhaust ??

bak · 03-31-2009, 07:03 AM

I have a 09 6 cylinder X6. I noticed yesterday that the passenger side exhaust did not have steam coming from it like the drivers side. I put my hand over it and felt nothing. I got under the car to find a gate or valve hooked up to a vacuum or electric solenoid. There is not one on the drivers side, only the passenger side. This is obviously controlled by the car. My question is does anyone no what the criteria is for this valve opening ? I know on a Ferrari most guys trick the vacuum solenoid by keeping the valves open at all times, this actually bypasses part of the exhaust for performance reasons. Its a little disapointing to see the car with dual tips and only one functional. Any help or comments would be appreciated.
Best,
Brian

bbdamon · 03-31-2009, 09:42 AM

run the car for like 5-10 mins, u will see steam come out from both side.... it takes time to heat up that twin turbo i guess!!

dmlgc · 03-31-2009, 10:37 AM

Quote:

Originally Posted by bak

I have a 09 6 cylinder X6. I noticed yesterday that the passenger side exhaust did not have steam coming from it like the drivers side. I put my hand over it and felt nothing. I got under the car to find a gate or valve hooked up to a vacuum or electric solenoid. There is not one on the drivers side, only the passenger side. This is obviously controlled by the car. My question is does anyone no what the criteria is for this valve opening ? I know on a Ferrari most guys trick the vacuum solenoid by keeping the valves open at all times, this actually bypasses part of the exhaust for performance reasons. Its a little disapointing to see the car with dual tips and only one functional. Any help or comments would be appreciated.
Best,
Brian

Looks like bbdamon answered although I have to wonder why have a valve/vacuum/etc if it opens up after 5-10 minutes, is it always open after that ?

bagbklyn · 03-31-2009, 02:15 PM

This also happens on 335 turbo engine as well, must be some great engineering behind the concept. Only happens for a few seconds then dual exhaust happens.

akraptor · 04-01-2009, 07:22 PM

I know that the second turbo (I guess the bigger one) start functioning only above a certain RPM level (maybe 3000?). So if BMW designed this car to save some fuel, why have gases come off both tips when iddling?! This car ain't like others. I mean, idle is as low as 500-650 RPM, and you expect to have gases on both pipes? ! It's the new fuel-saving technology. Forget the classic muscle cars memories. This is different.

shenard · 04-01-2009, 08:25 PM

Quote:

Originally Posted by akraptor

I know that the second turbo (I guess the bigger one) start functioning only above a certain RPM level (maybe 3000?). So if BMW designed this car to save some fuel, why have gases come off both tips when iddling?! This car ain't like others. I mean, idle is as low as 500-650 RPM, and you expect to have gases on both pipes? ! It's the new fuel-saving technology. Forget the classic muscle cars memories. This is different.

Aren't the turbos both the exact same size?

Where did you get this info?

xDrive50i · 04-02-2009, 04:31 AM

Quote:

Originally Posted by shenard

Aren't the turbos both the exact same size?

Where did you get this info?

The diesel version of the twin turbo I6 engine has two different sized turbos.

akraptor · 04-02-2009, 08:54 PM

Quote:

Originally Posted by xDrive50i

The diesel version of the twin turbo I6 engine has two different sized turbos.

Yes, this is correct. There are two turbos, but the one for smaller RPM's, ,is smaller too. . Plus, they had to snatch the smaller one somehow, around the big engine.

shenard · 04-02-2009, 09:02 PM

Quote:

Originally Posted by xDrive50i

The diesel version of the twin turbo I6 engine has two different sized turbos.

What about on the V8?

xDrive50i · 04-02-2009, 09:12 PM

Quote:

Originally Posted by shenard

What about on the V8?

The V8 has identical sized turbos.

Wouldn't be a good thing to have two different sized turbos on each bank of 4 cylinders

03-31-2009, 07:03 AM	#1
bak Private First Class 23 Rep 154 Posts Drives: X6 Join Date: Sep 2008 Location: Novi, MI iTrader: (0)	Dual Exhaust ?? I have a 09 6 cylinder X6. I noticed yesterday that the passenger side exhaust did not have steam coming from it like the drivers side. I put my hand over it and felt nothing. I got under the car to find a gate or valve hooked up to a vacuum or electric solenoid. There is not one on the drivers side, only the passenger side. This is obviously controlled by the car. My question is does anyone no what the criteria is for this valve opening ? I know on a Ferrari most guys trick the vacuum solenoid by keeping the valves open at all times, this actually bypasses part of the exhaust for performance reasons. Its a little disapointing to see the car with dual tips and only one functional. Any help or comments would be appreciated. Best, Brian
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03-31-2009, 09:42 AM	#2
bbdamon Private First Class 16 Rep 195 Posts Drives: X6 Join Date: Jul 2006 Location: stockton,ca iTrader: (0)	run the car for like 5-10 mins, u will see steam come out from both side.... it takes time to heat up that twin turbo i guess!!
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03-31-2009, 02:15 PM	#4
bagbklyn Private 9 Rep 59 Posts Drives: Future i4 M50 Join Date: Apr 2006 Location: Westchester iTrader: (0)	Happens on 335 turbo engine as well This also happens on 335 turbo engine as well, must be some great engineering behind the concept. Only happens for a few seconds then dual exhaust happens.
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04-01-2009, 07:22 PM	#5
akraptor Lieutenant 45 Rep 464 Posts Drives: 35 D Join Date: Jun 2008 Location: Romania iTrader: (0)	I know that the second turbo (I guess the bigger one) start functioning only above a certain RPM level (maybe 3000?). So if BMW designed this car to save some fuel, why have gases come off both tips when iddling?! This car ain't like others. I mean, idle is as low as 500-650 RPM, and you expect to have gases on both pipes? ! It's the new fuel-saving technology. Forget the classic muscle cars memories. This is different.
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