CDV delete -- E46 BMW

[Cadeez]

Anyone here done it personally on their car, or had it done? Sounds like a great mod that's basically free. Seems kind of like an appendix, it was put there for some reason yet you don't really know why and you can live without it. I need a weekend project, looking for input, thanks.

Found this DIY, not sure if it's legit though...
http://www.zeckhausen.com/CDV.htm#Benefits

[bullfrogs_M3]

Did it on my car. Easy 15 min job. Although I honestly couldn't tell the diff though because I also did UUC tranny mounts and OEM BMW ssk at the same time

[RITmusic2k]

Dane will probably chime in soon; he did it super quickly as well. I was going to do it a couple weeks ago, but I couldn't locate a proper lifting point to get my car raised with my racing jack

[bullfrogs_M3]

You can use my buddies site for further install instructions: http://www.my330i.com/mod27.php

ZECKHAUSEN MODIFIED CLUTCH DELAY VALVE
Completed 4/28/2004
DESCRIPTION
Replace stock Clutch Delay Valve with modified Zeckhausen unit.
PARTS NEEDED
1 - ZECKHAUSEN MODIFIED CLUTCH DELAY VALVE
(ZECKHAUSEN RACING $35)
TOOLS NEEDED
11mm Flair Wrench
15mm Wrench
Clear Rubber Bleeder Hose and Bottle
Brake Fluid

INSTALLATION
Most modern manual transmission BMWs come with a Clutch Delay or Lock Valve (CDV). The purpose of this valve, according to BMW, is to smooth out shifts and extend the life of driveline parts. It functions by only allowing hydraulic fluid to pass through it at a certain rate. Since it is inline on the clutch system, it effectively removes the ability to control your clutch use manually. It was designed to make the car nicer to drive for the average person. If you are reading this, you are not that average person! The CDV "dumbs" down the clutch pedal feel, and under hard driving, will actually cause the clutch disc to wear out *faster* due to slower engagement at high speed.

Thanks to the great people over at Zeckhausen Racing, they will provide BMW owners with a modified CDV for a small price, or modify one you send them, or provide you one for *free* if you send them two (2) stock original CDVs. Zeckhausen safely removes the internals of the CDV (without drilling) allowing it to go back into factory OEM location but now without interfering with clutch operation. These are modified factory parts and look, feel, and fit the same as your existing stock valve.

1. Park the car on a level surface and set the parking brake.

2. Jack up the front of the car and support it with jackstands.

3. Right forward of the clutch slave cylinder is a mounting point for the hydraulic line. The clutch delay valve can be see here both in and out of the car (Photos A & B).

4. I used a small plastic pair of locking pliers to crimp the rubber supply line about 3" away from this mount. This will keep excess fluid from draining out when you remove the CDV.

5. Using a 11mm Flair Wrench, disconnect the metal piping from CDV and pull the CDV from the bracket. A Flair Wrench grabs a nut/bolt on all six sides and is specifically designed to remove brake line and other hose nuts (Photo C). Be sure to use the correct tool for the job!

6. The CDV can then be removed from the supply line with a 15mm Wrench.

7. Replace with the modifed CDV and reconnect the lines. Hydraulic lines are flaired and need to be snug, but not overly tight.

8. Remove the hose clamp and prepare to bleed the clutch slave cylinder.

9. Open the hood and check that you have plenty of brake fluid in the master cylinder. The master cylinder feeds both the brakes and clutch system (Photo D).

10. Remove the rubber nipple on the slave cylinder bleeder screw (Photo E). Attach a length of rubber tubing and run that tubing into a small clear container filled partly with fresh brake fluid. You want to keep the end of this hose submerged at all times to keep air from creeping back into the system.

11. Attach a 8mm wrench to the bleeder valve and have a friend pump the clutch pedal a few times and then hold it down.

12. Open the bleeder for just a second. You will see the bubbles and fluid shoot down your rubber hose. Close the bleeder.

13. Have your friend pump the clutch pedal again and hold it. Again, crack the bleeder for a short period and close it.

14. I only needed to do this 3 times and I no longer saw bubbles. The system was now bled. If you have to do it more times than this, be sure to check on the master cylinder level periodically to make sure you have plenty of brake fluid and top off as needed.

15. Replace the bleeder nipple, check your connections for leaks, and go take it for a drive, you will notice the difference immediately!

[az3579]

DHHHUUUUUUUUUUU EEEEEEEEEEEEEEEEEEEETTTTTTTTTT!!

This is simply one of the MOST effective mods I've done to my car. It makes rev-matching possible!

[spencers]

Yep

[Crickett]

+1 Did it; dhuuu eeeet.

[kpro]

I did it. I took the cdv out and just connected the two lines togheter. I didn't buy a special cdv or anything. The difference is night and day, IMO.

[Cadeez]

Awesome, I'm gonna do it as soon as I can get it on a lift, thanks all!

[gr330zhp]

I did it when I swapped my tranny and diff fluid, makes an awesome difference and was really pretty quick to do

DHHHUUUUUUUUUUU EEEEEEEEEEEEEEEEEEEETTTTTTTTTT!!

This is simply one of the MOST effective mods I've done to my car. It makes rev-matching possible!

This, just need a throttle cable to perfect rev-matching. I hate Drive by wire, it makes a noticeable delay in response