6-sp Manual Transmission
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I thought the CDV was on the cars so manual (Not SMG) drivers cannot just dump the clutch at high rpms and cook the clutch. The delay allows for a slower let up off the clutch reguardless of how fast you dump the clutch. Of course of you are releaseing it slowly then there wouldnt be a problem.
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As far as I understand, the CDV (or cluth delay valve) is traditionally a one-way restrictor mechanism between the clutch slave cylinder and clutch master cylinder. The CDV essentially "delays" the engagement of the clutch and because of this delay, no matter how quickly you lift your foot off the clutch, the clutch engages the flywheel at a constant, even rate.
In theory, this saves the drivetrain and transmission from undue stress and shock, esp. if the driver were to inadvertantly (or intentionally) dump the clutch. In practice, however, the CDV simply increases the rate of wear and tear on the clutch and makes shifting gears less smooth. This is especially true in lower gears where constant clutch slippage can occur. During normal cruising and driving speeds, shifting from 1st to 2nd gear can be jerky, and even annoyingly uneven.
Some of the E46 M3 SMGs cars did indeed have a CDV (while others amazingly did not).
I am still under the impression that the SMG in the 5er has some sort of CDV built in.
In theory, this saves the drivetrain and transmission from undue stress and shock, esp. if the driver were to inadvertantly (or intentionally) dump the clutch. In practice, however, the CDV simply increases the rate of wear and tear on the clutch and makes shifting gears less smooth. This is especially true in lower gears where constant clutch slippage can occur. During normal cruising and driving speeds, shifting from 1st to 2nd gear can be jerky, and even annoyingly uneven.
Some of the E46 M3 SMGs cars did indeed have a CDV (while others amazingly did not).
I am still under the impression that the SMG in the 5er has some sort of CDV built in.
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Originally Posted by ipse dixit' post='229526' date='Jan 25 2006, 12:36 PM
As far as I understand, the CDV (or cluth delay valve) is traditionally a one-way restrictor mechanism between the clutch slave cylinder and clutch master cylinder. The CDV essentially "delays" the engagement of the clutch and because of this delay, no matter how quickly you lift your foot off the clutch, the clutch engages the flywheel at a constant, even rate.
In theory, this saves the drivetrain and transmission from undue stress and shock, esp. if the driver were to inadvertantly (or intentionally) dump the clutch. In practice, however, the CDV simply increases the rate of wear and tear on the clutch and makes shifting gears less smooth. This is especially true in lower gears where constant clutch slippage can occur. During normal cruising and driving speeds, shifting from 1st to 2nd gear can be jerky, and even annoyingly uneven.
Some of the E46 M3 SMGs cars did indeed have a CDV (while others amazingly did not).
I am still under the impression that the SMG in the 5er has some sort of CDV built in.
In theory, this saves the drivetrain and transmission from undue stress and shock, esp. if the driver were to inadvertantly (or intentionally) dump the clutch. In practice, however, the CDV simply increases the rate of wear and tear on the clutch and makes shifting gears less smooth. This is especially true in lower gears where constant clutch slippage can occur. During normal cruising and driving speeds, shifting from 1st to 2nd gear can be jerky, and even annoyingly uneven.
Some of the E46 M3 SMGs cars did indeed have a CDV (while others amazingly did not).
I am still under the impression that the SMG in the 5er has some sort of CDV built in.
With the CDV removed, you control the engagement and disengagement of the transmission with the entire play of the pedal. Hence smoother shifts for the experienced driver.
I actually found it easier to burn the clutch out with this rather un-natural device (CDV) especially when trying to inch while parking up a hill.
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