Question for E90Fleet

F32Fleet · 11-04-2005, 07:46 AM

My latest issue of Roundal had a piece about a Dinan Z4. One of the mods had to do with the airbox. Dinan stated their airbox actually removes as much H20 (90%) as the OEM version but unlike the OEM airbox, theirs actually has ram air characteristics. The article said the BMW stock airbox has a slight vacum(sp?).

E90Fleet · 11-04-2005, 09:03 AM

Most non-turbo/supercharged engine intakes run under a slight vacume

Think of it : The piston goes down in the cylinder with the intake valve open, this downwards movement causes a bit of a vacume because it has to draw the air in past the throttle and valves.

You can measure this vacume in the intake, most piston aircraft have a instrument showing "manifold pressure"

At small throttle openings there is a pressure well below atmosperic pressure ( vacume )
At wide open throttle you just about get atmosperic pressure

The BMW intake gives this pressure, now the Dinan one must somehow allow air to be rammed into the intake creating a pressure above atmospheric at wide open throttle.

Turbos and superchargers work the similarly. They use a fan to push more air into the intake, making the pressure in the intake greater that atmospheric pressure

LEDZEP · 11-04-2005, 09:33 AM

E90Fleet

F32Fleet · 11-04-2005, 09:48 AM

Quote:

Originally Posted by E90Fleet

Most non-turbo/supercharged engine intakes run under a slight vacume

Think of it : The piston goes down in the cylinder with the intake valve open, this downwards movement causes a bit of a vacume because it has to draw the air in past the throttle and valves.

You can measure this vacume in the intake, most piston aircraft have a instrument showing "manifold pressure"

At small throttle openings there is a pressure well below atmosperic pressure ( vacume )
At wide open throttle you just about get atmosperic pressure

The BMW intake gives this pressure, now the Dinan one must somehow allow air to be rammed into the intake creating a pressure above atmospheric at wide open throttle.

Turbos and superchargers work the similarly. They use a fan to push more air into the intake, making the pressure in the intake greater that atmospheric pressure

Clarification: I was under the impression from the Roundel article that the BMW airbox had a slight vacum pulling air away from the throttle body, not towards it. It didn't make sense to me, so I can only assume I misread the article. Thanks

tiga901 · 11-04-2005, 10:24 AM

E90Fleet, we salute you for your knowledge. Without you, this board will be just as boring at the other ones.

chris · 11-04-2005, 11:53 AM

e90fleet is a beast.

RichReg · 11-04-2005, 06:55 PM

"And on the 3rd day, God created E90Fleet"

ON325i · 11-04-2005, 07:17 PM

"And on the 4th day, E90Fleet created turbo charger."

puck724 · 11-04-2005, 09:31 PM

i wonder how big his head is right now....YOU DA MAN!!!

tightie · 11-04-2005, 09:36 PM

< lost

visor · 11-04-2005, 10:35 PM

Quote:

Originally Posted by tightie

< lost

Just do a search of e90fleet's posts and you will see how much he has singlehandedly contributed to the collective knowledge on this board.

e90fleet on his throne

RichReg · 11-05-2005, 08:01 PM

Quote:

Originally Posted by visor

e90fleet on his throne

ShinyRedCar · 11-15-2005, 06:37 AM

Quote:

Originally Posted by coreslogic

"And on the 4th day, E90Fleet created turbo charger."

I LOVE THIS PLACE!

11-04-2005, 07:46 AM	#1
F32Fleet Lieutenant General 3570 Rep 10,351 Posts Drives: 2015 435i Join Date: May 2005 Location: Southeastern US iTrader: (0)	Question for E90Fleet My latest issue of Roundal had a piece about a Dinan Z4. One of the mods had to do with the airbox. Dinan stated their airbox actually removes as much H20 (90%) as the OEM version but unlike the OEM airbox, theirs actually has ram air characteristics. The article said the BMW stock airbox has a slight vacum(sp?).
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11-04-2005, 09:03 AM	#2
E90Fleet Lieutenant General 1312 Rep 10,185 Posts Drives: BMW Join Date: Apr 2005 Location: South Africa iTrader: (0)	Most non-turbo/supercharged engine intakes run under a slight vacume Think of it : The piston goes down in the cylinder with the intake valve open, this downwards movement causes a bit of a vacume because it has to draw the air in past the throttle and valves. You can measure this vacume in the intake, most piston aircraft have a instrument showing "manifold pressure" At small throttle openings there is a pressure well below atmosperic pressure ( vacume ) At wide open throttle you just about get atmosperic pressure The BMW intake gives this pressure, now the Dinan one must somehow allow air to be rammed into the intake creating a pressure above atmospheric at wide open throttle. Turbos and superchargers work the similarly. They use a fan to push more air into the intake, making the pressure in the intake greater that atmospheric pressure
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11-04-2005, 09:33 AM	#3
LEDZEP Lieutenant General 417 Rep 12,276 Posts Drives: 2009 E70 & 2011 F25 Join Date: Jun 2005 Location: Area 51 iTrader: (0) Garage List 2011 X3 35i M Sport [7.62] 2009 X5 M Sport [0.00] 2007 328xi E90 [0.00] 2006 325xiT E91 [0.00]	E90Fleet __________________ I think it is bad luck to be superstitious
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11-04-2005, 10:24 AM	#5
tiga901 Second Lieutenant 7 Rep 244 Posts Drives: e90 330i, mt pp sp Join Date: Sep 2005 Location: Millbrae, CA iTrader: (0)	E90Fleet, we salute you for your knowledge. Without you, this board will be just as boring at the other ones.
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11-04-2005, 11:53 AM	#6
chris Second Lieutenant 5 Rep 281 Posts Drives: Jet Black e90 330i Join Date: Aug 2005 Location: Bay Area, CA iTrader: (0)	e90fleet is a beast.
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11-04-2005, 06:55 PM	#7
RichReg Colonel 121 Rep 2,099 Posts Drives: 2015 435Xi GC & 2000 323Ci. Join Date: Apr 2005 Location: New Jersey iTrader: (0)	"And on the 3rd day, God created E90Fleet"
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11-04-2005, 07:17 PM	#8
ON325i Captain 18 Rep 740 Posts Drives: e90 325i Join Date: Aug 2005 Location: Toronto, Canada iTrader: (0) Garage List 2006 e90 325i [0.00]	"And on the 4th day, E90Fleet created turbo charger." __________________ e90 325i Jet Black / Sports Pkg / Auto
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11-04-2005, 09:31 PM	#9
puck724 COLTS 4 LIFE!!! 99 Rep 1,746 Posts Drives: 2006 330i Join Date: Aug 2005 Location: california iTrader: (1) Garage List 2006 330i [0.00]	i wonder how big his head is right now....YOU DA MAN!!! __________________ 2006 330i --sapphire black--black leather --alumminum trim --premium package --cold weather package --park distace control --automatic transmission --navigation with iDrive
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11-04-2005, 09:36 PM	#10
tightie JOSH SHOKRI. 524 Rep 5,881 Posts Drives: 991 GT3RS, 964, Raptor Join Date: Aug 2005 Location: los angeles, california. iTrader: (7) Garage List 2008 BMW M3 [7.90]	< lost __________________ Current: 16 991 GT3RS , 91 964 C2, 17 Raptor \| Past: 2015 991 GT3, 2015 i3,15 YMB F80 M3, 13 E92 M3 DCT, 08 E92 M3 6MT, 07 E60 M5, 02 E46 M3 Instagram: @josh_speeddistrict #SpeedDistrict @SpeedDistrict
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