Thanks Sixspeed

[All Pina]

Not been posting much since the demise of Z4UM - thanks for pointing me in this direction.

CDV delete is great by the way, and still thinking about the springs.

Best

AP

 

[sp3ctre]

CDV delete is great by the way

Nice one... can you explain the difference for us?... and nobody has done a how-to for that yet, don't suppose you took pics?

 

[sixspeed]

There *was* one on Z4UM.. not sure if it could be found through the caching on Google etc..

I'll have a rummage...

 

[All Pina]

CDV delete is great by the way

Nice one... can you explain the difference for us?.

In a nutshell - the CDV is a constricting valve in the clutch fluid line - as you dump the clutch, it delays the release in fluid pressure; causing the clutch to bite more slowly (hence delay valve). If you are a fan of slick gear changes, this is a major PITA. Swapping it out for a non constricted look alike, improves clutch "feel" but maintains the OEM look to nosey dealers.

As there was no CDV on my Alpina, this was the first mod to do. Sixspeed's mate did the fitting for me in about 20 mins.

As Six says - there was a great "how to" on the old Z4UM and it can be done DIY if you are reasonably competent (ie not me !)

 

[pvr]

We just did one last saturday on a M. Waste of time on a M, hardly any difference ...

 

[sixspeed]

pvr, you're not the first person to say this (about the M), but it's totally out from my findings. I could easily tell the difference in the first 10 seconds without the CDV, to how it was before....

Not saying you're wrong, but i wonder why there's such a mixture of people who say it does or doesn't do anything on the M. On other models, the opinions seem to be unanimous...

 

[pvr]

I did my 3.0 before, and the difference was big. When I got the M, I found it pretty much like my 3.0 was after delete.

Driving the M after delete, it was very much - hmm, not worth the effort really ...

 

[JayD]

CDV delete is great by the way

Nice one... can you explain the difference for us?... and nobody has done a how-to for that yet, don't suppose you took pics?

Some details on it here, apologies if been posted before:

http://www.zeckhausen.com/cdv.htm

 

[20ducks]

It took me 10 shifts to figure out that I will do this mod ASAP. I went from a steptronic to 6 speed (going from 03 2.5 Z4 to 06 3.0 Z4). Easy mod if you have a floor jack and stands.

 

[PeteH]

I did my 3.0 before, and the difference was big. When I got the M, I found it pretty much like my 3.0 was after delete.

Driving the M after delete, it was very much - hmm, not worth the effort really ...

I noticed a difference but it wasn't massive. It was more apparent in 3rd to 4th changes as the slight clunk disappeared. There was no noticeable difference between 1st and 2nd where it is supposed to be most noticeable.

 

[pvr]

It took me 10 shifts to figure out that I will do this mod ASAP. I went from a steptronic to 6 speed (going from 03 2.5 Z4 to 06 3.0 Z4). Easy mod if you have a floor jack and stands.

On the 3.0 models (as well as manual 2.5), the difference was indeed very big. The CDV of the M is different

 

[Samiad]

I still need to find a garage in the UK that can perform this for me

 

[pvr]

You need to get the part first from Zeckhausen, is about $25

 

[All Pina]

We just did one last saturday on a M. Waste of time on a M, hardly any difference ...

Sorry - but I REALLY noticed the difference. No Kangarooing from 1st to 2nd and, IMHO, a slicker change. Each to his/her own

 

[All Pina]

The CDV of the M is different

How so? I am looking at my old one now and the "bore" is marked as 1.3mm dia vs around 5mm on the Zeckhausen that went on.

The part number on the old CDV is 1 165 829 UK - so maybe they vary from market to market.

 

[pvr]

6755897 uk is the original part number I have for the 3.0 I took out on my previous car.

It also has a different partnumber on the Zeckhausen site for the non M versus the M. You can see below the differences.

 

[All Pina]

CORRECTION

My "old" one looks identical to your top pic - as did the one I got from Zeck (and I think you are saying that these are the M versions ??)

Anyway - now totally confused, but I love my gear change :

 

[pvr]

I suppose each car must have there own severity of the issue.

The top unit is the M unit anyway ..., but being that you can remove the CDV altogether I don't suppose it makes any difference what you put in between the pipes as long as the hole is bigger.

Don't get me wrong - if I could be bothered to do it again, I would do it but having experienced the difference between the 3.0 with / without (big change) and now another M without (little change), I was not encouraged enough to change mine.