BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Engine, Transmission, Exhaust, Drivetrain, ECU Software Modifications
 
Post Reply
 
Thread Tools Search this Thread
      07-27-2008, 03:41 PM   #1
rawedge2
First Lieutenant
rawedge2's Avatar
17
Rep
332
Posts

 
Drives: 05 STI - 08 M3
Join Date: Dec 2007
Location: long island

iTrader: (1)

Does the e92 M3 have a Clutch Delay Valve?!?!



i asked about removing the CDV valve in this thread and recieved good info bout how members have done it and feel improvements in
This thread:
http://www.m3post.com/forums/showthread.php?t=137608

and now came across this, that it dosen't exist..
here:
http://www.m3post.com/forums/showthread.php?t=153462

clarification..?? since i haven't attempted the mod yet
Appreciate 0
      07-27-2008, 05:32 PM   #2
rmashman
Private
4
Rep
59
Posts

 
Drives: 2008 M3
Join Date: Nov 2007
Location: San Diego

iTrader: (0)

More confirmation-no CDV.

In the message above, there is a link to my original post.

In this previous post, I note that the M3 part that I got from my dealer was a clear pipe without the valve inside.

The part did not have any painted marking on it like the 335 valve. The 335 pipe looks identical on the outside to the M3 part except that it has a very noticable white painted number 25 and two bands painted around the part.

I did have a chance to take off the transmission cover on my car and did observe the that the pipe at issue has no markings like the M3 pipe gotton from my dealer as opposed to the 335 valve pipe which has painted markings. I take this as further evidence that there is no CDV valve.

Perhaps the member who took their part off of the M3 could measure the inside diameter and let us know what the measurement is. If it is 4mm plus there is no CDV in the housing.

Rob
Appreciate 0
      07-29-2008, 08:58 PM   #3
Mike Benvo
BimmerPost Supporting Vendor
Mike Benvo's Avatar
United_States
98
Rep
4,813
Posts


 
Drives: Harrop SC M3 / E46 M3 / 7Turbo
Join Date: Apr 2008
Location: SoCal

iTrader: (7)

Garage List
2008 BMW M3  [5.00]
1990 BMW 735i Turbo  [5.00]
2004 BMW M3  [0.00]
Send a message via Skype™ to Mike Benvo
Yes it does have a clutch delay valve, called a "lock valve". I removed it and the shifting is much crisper now.
__________________

-----| Like us on Facebook | Instagram || Tuning Information | Remote Coding |-----
----Visit us at www.BPMSport.com - Emotion. Driven. | Toll Free: (888) 557-5133----
Appreciate 0
      07-29-2008, 09:53 PM   #4
GregW / Oregon
Commander-In-Chief
United_States
137
Rep
7,647
Posts

 
Drives: 2015 M4 Coupe, 2012 ML350
Join Date: Nov 2005
Location: Lake Oswego, OR

iTrader: (2)

Garage List
CDV

Quote:
Originally Posted by Mike Benvo View Post
Yes it does have a clutch delay valve, called a "lock valve". I removed it and the shifting is much crisper now.
Here it is in the diagram, #13 lock valve, but I haven't checked mine yet. I removed mine on the E46, but the difference was negligible, IMO.
Attached Images
 
__________________

Greg Lake Oswego, Oregon, USA
2015 M4 Coupe - Silverstone/Sakhir/CF
2012 ML350
Appreciate 0
      07-29-2008, 09:53 PM   #5
DJ9
Captain
DJ9's Avatar
United_States
16
Rep
657
Posts

 
Drives: 2008 E92 M3_SG
Join Date: Feb 2008
Location: San Francisco/Marin County, CA

iTrader: (0)

Garage List
2008 M3  [0.00]
Quote:
Originally Posted by Mike Benvo View Post
Yes it does have a clutch delay valve, called a "lock valve". I removed it and the shifting is much crisper now.
You removed this yourself? DIY write up possibly
__________________
-Dave


2008 E92M3-Space Gray
Eisenmann Sport Exhaust_MT/Loaded
Appreciate 0
      07-29-2008, 09:58 PM   #6
GregW / Oregon
Commander-In-Chief
United_States
137
Rep
7,647
Posts

 
Drives: 2015 M4 Coupe, 2012 ML350
Join Date: Nov 2005
Location: Lake Oswego, OR

iTrader: (2)

Garage List
CDV removal DIY

Quote:
Originally Posted by DJ9 View Post
You removed this yourself? DIY write up possibly
Hey, you unscrew it, take it out, and reconnect. Only thing is you need to bleed the system then. Also, slight chance, but clutch replacement under the BMWNA maintenance plan could be denied.

This is for the E46 M3, but basically the same (thanks to Mike):

http://m3.madrussian.net/diy_cdv.shtml

http://m3.madrussian.net/diy_brake_bleed.shtml
__________________

Greg Lake Oswego, Oregon, USA
2015 M4 Coupe - Silverstone/Sakhir/CF
2012 ML350
Appreciate 0
      07-29-2008, 11:12 PM   #7
1ne
First Lieutenant
1ne's Avatar
Canada
3
Rep
338
Posts

 
Drives: '08 E92 M3 JZB 6MT
Join Date: Jul 2008
Location: Edmonton

iTrader: (0)

Greg you got the best technical pictures. Mind sharing where you are getting this?
Appreciate 0
      07-30-2008, 12:09 AM   #8
DJ9
Captain
DJ9's Avatar
United_States
16
Rep
657
Posts

 
Drives: 2008 E92 M3_SG
Join Date: Feb 2008
Location: San Francisco/Marin County, CA

iTrader: (0)

Garage List
2008 M3  [0.00]
Quote:
Originally Posted by GregW / Oregon View Post
Hey, you unscrew it, take it out, and reconnect. Only thing is you need to bleed the system then. Also, slight chance, but clutch replacement under the BMWNA maintenance plan could be denied.

This is for the E46 M3, but basically the same (thanks to Mike):

http://m3.madrussian.net/diy_cdv.shtml

http://m3.madrussian.net/diy_brake_bleed.shtml
Thanks again Greg.
__________________
-Dave


2008 E92M3-Space Gray
Eisenmann Sport Exhaust_MT/Loaded
Appreciate 0
      07-30-2008, 01:05 AM   #9
lucid
Major General
lucid's Avatar
United_States
116
Rep
8,034
Posts

 
Drives: E30 M3; Expedition
Join Date: Apr 2007
Location: USA

iTrader: (0)

I don't get it. The OP in that other thread clearly says that the part is simply acting like a connector and does not have a valve inside like the E46 CDV's had. So, what does removing the connector change exactly?
__________________
Appreciate 0
      07-30-2008, 06:23 AM   #10
J08M3
Major General
J08M3's Avatar
United_States
102
Rep
6,012
Posts

 
Drives: 2011 M3 COUPE
Join Date: May 2008
Location: NEW YORK

iTrader: (8)

This is kinda strange. Half the people say they've changed it and it makes a difference and the other half the people that have taken it out say there is no valve in there. If you ask me, my car drives great and I have no problem with the clutch. So even if there is a CDV it certainly isn't causing any problems for me.
__________________
Appreciate 0
      07-30-2008, 07:31 AM   #11
Mickb
Private First Class
4
Rep
137
Posts

 
Drives: AW/FR E92 M3 DCT
Join Date: Apr 2008
Location: Ireland

iTrader: (0)

Quote:
Originally Posted by J08M3 View Post
This is kinda strange. Half the people say they've changed it and it makes a difference and the other half the people that have taken it out say there is no valve in there. If you ask me, my car drives great and I have no problem with the clutch. So even if there is a CDV it certainly isn't causing any problems for me.
Its a classic example of internet placebo effect. These boards (and others I might add) are littered with examples of people changing minor stuff on their cars and claiming massive differences (when I suspect in a blind testing of two cars they would not be able to tell the difference).

And the E46 cdv thing always surprised me anyway. Virtually noone in Europe (where 99% of people learn to drive with MT's) did the mod (or felt it was required), whereas loads of people in the US (where 99% of people learn to drive autos) claimed the stock transmission was rubbish and the cdv removal was essential.

Mick
Appreciate 0
      07-30-2008, 08:08 AM   #12
J08M3
Major General
J08M3's Avatar
United_States
102
Rep
6,012
Posts

 
Drives: 2011 M3 COUPE
Join Date: May 2008
Location: NEW YORK

iTrader: (8)

classic example of mind over matter?
__________________
Appreciate 0
      07-30-2008, 09:00 AM   #13
lucid
Major General
lucid's Avatar
United_States
116
Rep
8,034
Posts

 
Drives: E30 M3; Expedition
Join Date: Apr 2007
Location: USA

iTrader: (0)

If the connector does not result in reduction of cross-section, and thus, impedence of flow, there can be no real effect...rmashman is saying he took the connector out, inspected it, and observed that it was just a hollow connector.

So we have:

a) rmashman is mistaken
b) other M3s have different type of connectors/parts than the one rmashman investigated
c) others who have taken the connector/part out and claim they are experiencing an effect are the cause of the effect and not the connector/part in question

I'm kind of leaning toward c here, but all three are possible I guess.
__________________
Appreciate 0
      07-30-2008, 09:57 AM   #14
GregW / Oregon
Commander-In-Chief
United_States
137
Rep
7,647
Posts

 
Drives: 2015 M4 Coupe, 2012 ML350
Join Date: Nov 2005
Location: Lake Oswego, OR

iTrader: (2)

Garage List
CDV

Quote:
Originally Posted by lucid View Post
If the connector does not result in reduction of cross-section, and thus, impedence of flow, there can be no real effect...rmashman is saying he took the connector out, inspected it, and observed that it was just a hollow connector.
Why would BMW install it if it has no effect? It is not needed as a "connection", as the hydraulic hose will connect fine without it.
__________________

Greg Lake Oswego, Oregon, USA
2015 M4 Coupe - Silverstone/Sakhir/CF
2012 ML350
Appreciate 0
      07-30-2008, 10:43 AM   #15
lucid
Major General
lucid's Avatar
United_States
116
Rep
8,034
Posts

 
Drives: E30 M3; Expedition
Join Date: Apr 2007
Location: USA

iTrader: (0)

Quote:
Originally Posted by GregW / Oregon View Post
Why would BMW install it if it has no effect? It is not needed as a "connection", as the hydraulic hose will connect fine without it.
I don't know. I haven't seen the hose and the connector, so I can't say what it might or might not be doing. Are you sure the hose would be just as secure without it? Again, if there is no change in cross section, I don't see how it can impede the flow. Have you seen it? Is there really no reduction of the diameter throughout the connector? Well, I guess the connector wall might have a different surface finish than the finish of the hose, but that should be an insignificant effect. Another possibility is that the hose might need to have some slack in it to meet some spec, and they don't want to manufacture a specific hose for the M3, and the are using the dummy connector--if that is indeed what it is--not to strain the hose. Many possibilities...
__________________
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 Off
Forum Jump


All times are GMT -5. The time now is 12:01 AM.




m3post
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST