Clutch delay valve
- Thread starter Z4M-2006
- Start date
The CDV was put in the driveline to stop damage to the centreplate of the clutch..
You have to seriously abuse a clutch to break it,its not unheard of for the centreboss of the driveplate to disintegrate but i have never seen it on a standard car... Modded cars on standard clutch isnt uncommon.
The CDV was a crap idea,not the first or the last i suspect from BMW... The car is simply better without it,no other manufacturers use it.
If you can modulate your left foot correctly,there is absolutely no need for it at all..
You have to seriously abuse a clutch to break it,its not unheard of for the centreboss of the driveplate to disintegrate but i have never seen it on a standard car... Modded cars on standard clutch isnt uncommon.
The CDV was a crap idea,not the first or the last i suspect from BMW... The car is simply better without it,no other manufacturers use it.
If you can modulate your left foot correctly,there is absolutely no need for it at all..
Don't most people remove the CDV to reduce kangarooing in first second and third? Surely removing this would increase the kangarooing ? As the small amounts of slip the CDV allows will smooth out harder gear changes?
simonlpearce
Senior member
CDV was put in for the yanks as most of the drive auto and can't handle a stick shift so they kill the clutches.
Us Brits that know how to drive properly don't need them
Us Brits that know how to drive properly don't need them
TiffAnsell said:
Imho the cdv causes kangarooing.
Imagine the clutch not being fully engaged when power is appied. At some point it will engage and the driveline will jerk. The point of engagement is harder to control because it is retarded compared to your clutch pedal action (depending on how fast you operate the pedal, so also not easy to predict). But we're talking 1/10 to maybe half a second here, but that is the margin you use with spirited driving.
On the one hand the reason for a cdv is said to protect the driveline, where power cant be applied in one direct blow. But everyone that has had proper drivers training knows that during the shift/clutch action you should only apply little power (to match revs), and only give full throttle when the clutch is fully engaged. (that becomes even more important in high powered cars like a z4m (of even more powerful cars), or you will destroy your clutch eventually.
So in that pov it makes no sense to install a CDV unless you don't know how to shift properly.
On the other hand the reason for a cdv is that you dont apply the clutch too abruptly that the engine stalls. So as a failsave for people who don't know how to shift properly.
Adding both the above reasons to install the CDV, you can only conclude it is ment for people who don't know how to shift properly
