E46 BMW Social Directory E46 FAQ 3-Series Discussion Forums BMW Photo Gallery BMW 3-Series Technical Information E46 Fanatics - The Ultimate BMW Resource BMW Vendors General E46 Forum The Tire Rack's Tire Wheel Forum Forced Induction Forum The Off-Topic The E46 BMW Showroom For Sale, For Trade or Wanting to Buy

Welcome to the E46Fanatics forums. E46Fanatics is the premiere website for BMW 3 series owners around the world with interactive forums, a geographical enthusiast directory, photo galleries, and technical information for BMW enthusiasts.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us.

Go Back   E46Fanatics > E46 BMW > General E46 Forum

General E46 Forum
This is the place to get answers, opinions and everything you need related to your E46 (sedan, coupe, convertible and wagon) BMW!

Reply
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 06-21-2002, 04:28 PM   #1
BAVARIAN323i
Ballin'
 
Join Date: Dec 1969
Location: Boston, Ma
Posts: 2,504
My Ride: 1999 323i
Send a message via AIM to BAVARIAN323i
Question about the intake...

I video taped the engine while reving it with the stock and ecis intake.
When the stock intake was in, two little doors simutaneously opened with the reving, on either side of the grill. With the ecis they did not open.
does anyone know why?
__________________
SOLD

1999 e46
-Jim Confronti Shark Injector Software
-18x8.5 Breyton Inspirations
-Bridgestone S-03 Potenza Pole Positionís
-H&R CupKit w/ M3 RSM & Z3 plate
-UUC Pedals
-European Lights w/ Silvervision Bulbs all around
-DEI Shock Sensor
BAVARIAN323i is offline   Reply With Quote
Ads by Google

Guests, get your FREE E46Fanatics.com membership to remove this ad.
Old 06-21-2002, 04:30 PM   #2
drewcon
Bavarian Motor Slave
 
Join Date: Dec 1969
Location: Boston
Posts: 1,545
My Ride: 330ci
little doors?

no clue...so why did i even respond you ask, I'm not sure.:tongue:
drewcon is offline   Reply With Quote
Old 06-22-2002, 03:49 AM   #3
Jspeed
Registered User
 
Join Date: Dec 1969
Location: Vancouver, BC, Canada
Posts: 1,990
My Ride: '01 330i
I think I know what you're talking about. Those flaps open up when the throttle opens beyond a certain point. When you video taped the ECIS, was the hood open? If so, the heat-shielded area would not be enclosed and the vacuum wouldn't be great enough to open up any of those flaps.
Jspeed is offline   Reply With Quote
Old 06-22-2002, 08:54 AM   #4
KevinJ_2k1_325ci
Registered User
 
Join Date: Dec 1969
Location: Alexandria, VA
Posts: 3,083
My Ride: 2001 325ci
Exactly

Remember that the ECIS doesn't rely alone on the intake grill. It also is getting a fair amount of air from the front headlight below the bumper. If a great enough vaccum is created those little flaps will open but are negligable with the ECIS since it's getting more air from other areas.

Quote:
Originally posted by Jspeed
I think I know what you're talking about. Those flaps open up when the throttle opens beyond a certain point. When you video taped the ECIS, was the hood open? If so, the heat-shielded area would not be enclosed and the vacuum wouldn't be great enough to open up any of those flaps.
KevinJ_2k1_325ci is offline   Reply With Quote
Old 06-22-2002, 10:45 AM   #5
BAVARIAN323i
Ballin'
 
Join Date: Dec 1969
Location: Boston, Ma
Posts: 2,504
My Ride: 1999 323i
Send a message via AIM to BAVARIAN323i
ok, the only thing is that I videoed it with the hood open for both the stock and ECIS. The doors opened for the stock, and not the ecis
__________________
SOLD

1999 e46
-Jim Confronti Shark Injector Software
-18x8.5 Breyton Inspirations
-Bridgestone S-03 Potenza Pole Positionís
-H&R CupKit w/ M3 RSM & Z3 plate
-UUC Pedals
-European Lights w/ Silvervision Bulbs all around
-DEI Shock Sensor
BAVARIAN323i is offline   Reply With Quote
Old 06-22-2002, 02:01 PM   #6
Jspeed
Registered User
 
Join Date: Dec 1969
Location: Vancouver, BC, Canada
Posts: 1,990
My Ride: '01 330i
Quote:
Originally posted by BAVARIAN323i
ok, the only thing is that I videoed it with the hood open for both the stock and ECIS. The doors opened for the stock, and not the ecis
Yes, but the stock airbox is self-enclosed, where the ECIS relies the hood to be closed to complete the enclosure.
Jspeed is offline   Reply With Quote
Old 06-22-2002, 02:08 PM   #7
B
OG Moderator Extraordinaire
 
B's Avatar
 
Join Date: Mar 2001
Location: NJ
Posts: 5,619
My Ride: 325iX-M3-525iT-M5
Send a message via AIM to B
Quote:
Originally posted by Jspeed

Yes, but the stock airbox is self-enclosed, where the ECIS relies the hood to be closed to complete the enclosure.
yup!
__________________
B is offline   Reply With Quote
Old 06-22-2002, 03:58 PM   #8
simsima325
'a certain moderator'
 
simsima325's Avatar
 
Join Date: Feb 2001
Location: Hyattsville, MD
Posts: 37,764
My Ride: Honda Civic
what if you got rid of these little doors? would you see an increase in power, even with throtle aplications that before would not have created the vacuum to open the doors?
-brendan
simsima325 is offline   Reply With Quote
Old 06-23-2002, 12:26 AM   #9
KevinJ_2k1_325ci
Registered User
 
Join Date: Dec 1969
Location: Alexandria, VA
Posts: 3,083
My Ride: 2001 325ci
Here's the deal

Since at low end RPM, the throttle is almost completely closed under 2500 RPM, there's very little need for air intake. Once speed builds above 25mph the doors will probably open letting more air in thus letting more air into the throttle. The RPM from 0-2500 relies purely on a small amount of air and more gas mixture for combustion which the ECU takes care of automatically. This is why you need your ECU tuned with a cold air intake if you want to take advantage of it at low end speed, otherwise all the benefit is mostly at the high end RPM.

Bottom line, you will get no benefit from opening the little doors. Get a cold air intake instead with a tuned ECU.
KevinJ_2k1_325ci is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Censor is ON





All times are GMT -5. The time now is 01:24 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
(c) 1999 - 2011 performanceIX Inc - privacy policy - terms of use