How to modify your CDV (Clutch Delay Valve)

I've just got back from fitting a modified CDV. First impressions are excellent, a must-do mod.
 
Can someone explain what the actual mod is, and what it achieves? Sorry for being a numpty, but i've read it through and i'm struggling to figure out the purpose.
 
The CDV (Clutch Delay Valve) mod removed the delay valve so that when you take your foot of the clutch the clutch is released at the rate you determine and not the rate of the valve.

No delay is applied when you put your foot on the clutch but it is when you take your foor off, it is there for people who cannot drive properly and to reduce drivetrain shock, but it will increase clutch wear and make changing gear smoothly very difficult.

It really is one of the best and cheapest mods you can do.
 
Does this mod apply to SMG models? I realise I don't have a clutch, but I have no idea if there's something doing a similar job in its stead within the SMG system.

And yes, I am mechanically retarded, so please excuse the stupidity of this question. I really do wish I knew the slightest about car mechanics, but I've no idea how to start.
 
Sorry for being a spaz but I just wanna check I've got this right...

This part is taken off completely
http://www.z4-forum.com/user_images/srhutch/cdv1.jpg

and the hose is just put back on without it?

Whereabouts is it located?

Thanks again.
 
You can either take that valve off completely and reconnect the pipe directly - although some say it might make the pipe too tight - or you can remove the insert (as shown in the picture you posted) and refit it.

I can't find the instructions for the Z4, but they're similar on most models (although you've got to remove the panels under the engine/gearbox to get to the valve)

These instructions might help - http://www.bmw325i.net/cdv_removal.shtml - although it might take longer to read them than to do the job :thumbsup:
 
No the CDV isnt removed completely, the CDV is removed from the car, and the internal removed from that then the CDV is re fitted.
 
srhutch said:
No the CDV isnt removed completely, the CDV is removed from the car, and the internal removed from that then the CDV is re fitted.

Yes it can be removed completely. The pipe just screws up without the short length of connector containing the restrictor. People replace with a new 'opened up' valve to keep the original look in case of warranty claims.
 
Tref said:
srhutch said:
No the CDV isnt removed completely, the CDV is removed from the car, and the internal removed from that then the CDV is re fitted.

Yes it can be removed completely. The pipe just screws up without the short length of connector containing the restrictor. People replace with a new 'opened up' valve to keep the original look in case of warranty claims.

I am aware of that but most like to keep stealth for warrany reasons etc
 
Has anybody had this done in the South of England? I want to get this done but am a bit wary about giving it to just anybody to do and don't have the ability to do it myself.
 
flimper said:
Has anybody had this done in the South of England? I want to get this done but am a bit wary about giving it to just anybody to do and don't have the ability to do it myself.

I got it fitted at a garage near Brand Hatch. They're BMW specialists and come highly recommended from a friend with a CSL. ETA Motorsport, West Kingsdown (Right opposite the Texaco garage near the main entrance to Brands.) 01474 850505. They're an excellent bunch of guys, highly recommended.
 
mmm-five said:
You can either take that valve off completely and reconnect the pipe directly - although some say it might make the pipe too tight - or you can remove the insert (as shown in the picture you posted) and refit it.

I can't find the instructions for the Z4, but they're similar on most models (although you've got to remove the panels under the engine/gearbox to get to the valve)

These instructions might help - http://www.bmw325i.net/cdv_removal.shtml - although it might take longer to read them than to do the job :thumbsup:

Thanks, good guide.

I'm gunna have to give this a go, since I've read this post the clutch action has been annoying me! A job for the weekend me thinks.
 
flimper said:
Has anybody had this done in the South of England? I want to get this done but am a bit wary about giving it to just anybody to do and don't have the ability to do it myself.

I had the guys at TCS in High Wycombe wip mine out and bleed the fluid etc. Simple job.
 
i will have my car up on the jack this weekend so i think i might give it a go. only good results heard so far.

is the new bit of braided hose completely necessary?
 
mmm-five said:
You can either take that valve off completely and reconnect the pipe directly - although some say it might make the pipe too tight - or you can remove the insert (as shown in the picture you posted) and refit it.

I can't find the instructions for the Z4, but they're similar on most models (although you've got to remove the panels under the engine/gearbox to get to the valve)

These instructions might help - http://www.bmw325i.net/cdv_removal.shtml - although it might take longer to read them than to do the job :thumbsup:

As per step 15 in the guide, it referres to a minor bleed. Whats the difference? I don't fancy doing a full bleed of the fluid as it was changed not that long ago.
 
Rudd_2002 said:
i will have my car up on the jack this weekend so i think i might give it a go. only good results heard so far.

is the new bit of braided hose completely necessary?

No, just remove the valve and screw it all back together. Couldn't be simpler from a technical viewpoint. Just make sure there is no air in the system.
 
Spud said:
Does this mod apply to SMG models? I realise I don't have a clutch, but I have no idea if there's something doing a similar job in its stead within the SMG system.

And yes, I am mechanically retarded, so please excuse the stupidity of this question. I really do wish I knew the slightest about car mechanics, but I've no idea how to start.
Anyone? :(
 
Spud said:
Spud said:
Does this mod apply to SMG models? I realise I don't have a clutch, but I have no idea if there's something doing a similar job in its stead within the SMG system.

And yes, I am mechanically retarded, so please excuse the stupidity of this question. I really do wish I knew the slightest about car mechanics, but I've no idea how to start.
Anyone? :(

No, it is not relevant to SMG models.

There is no salvation :P
 
they must have changed the design to more securely house the insert (A) - Ive just tried on a new valve I received yesterday - as you laziomonster drill bit just pushed right the way through leaving it probably impossible to remove the insert...

oh and I was holding the valve in my fingers, so now have a cut thumb :o

Ive lived with it for 3 years... might just have to live with it for a few more!
 
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