[kern417]

I made a video on how to remove the CDV from our cars. It's pretty easy to do. I start off by explaining how it works and why it may or may not be worth doing. If you already understand that part, feel free to skip forward.

Shoutout to TurboAra for finding it first. More discussion in his thread:
https://f30.bimmerpost.com/forums/sh....php?t=1486773

[akgambino]

This is awesome, so much more clear to understand this DIY with a video. Excellent work!

When you were talking about the potential for the clutch to be able to handle more torque with the CDV removed (around 3:00 in the video) I always felt like that would be true but other clutch posts on this forum say it makes no difference at all. My car FBO with custom stg2 bm3 tune (91oct, stock pwg turbo) seems to slip the clutch in 3/4/5/6 gear when going near or at WOT at any rpm below say 3500 due to too much torque.

I noticed you mentioned you were also replacing clutch, I wish someone with a fbo stg2 car that has clutch slipping would do this mod first and report back about what effect it has but instead it seems every person who has what appears to be clutch slipping just fast forwards to replacing the clutch lol

[kern417]

Originally Posted by akgambino

This is awesome, so much more clear to understand this DIY with a video. Excellent work!

When you were talking about the potential for the clutch to be able to handle more torque with the CDV removed (around 3:00 in the video) I always felt like that would be true but other clutch posts on this forum say it makes no difference at all. My car FBO with custom stg2 bm3 tune (91oct, stock pwg turbo) seems to slip the clutch in 3/4/5/6 gear when going near or at WOT at any rpm below say 3500 due to too much torque.

I noticed you mentioned you were also replacing clutch, I wish someone with a fbo stg2 car that has clutch slipping would do this mod first and report back about what effect it has but instead it seems every person who has what appears to be clutch slipping just fast forwards to replacing the clutch lol

I have no data to prove it, so take it with a grain of salt. I just wanted to explain the theory because it does seem plausible. However, it's more likely to fix slip after shifting. Low RPM torque causing slip probably won't be fixed with this, since this affects clutch engagement.

And I really did toss the idea around for a while. I don't have any slip now, so would it hold at least on the 1st base map of my custom tune? Maybe. But ultimately I don't want the clutch to slip, ruin the flywheel, and then my bill for replacement is twice as much. Plus, if I'm going through revisions of my tune, I don't want to suddenly stop development because additional torque in rev 3 of the tune caused it to slip. I'm just going to do it now while the weather is crappy and I'm not driving the car much anyway. At most I'd guess it's an incremental improvement.

I have seen others indicate that it seemed to help, but that doesn't mean it won't start slipping again as the clutch racks up more miles. I'd have to find the post again but I believe it was in the B58 Bootmod3 thread where people started seeing clutch slip on the Stage 2 E30 tune.

[kierownik]

Originally Posted by kern417

I made a video on how to remove the CDV from our cars. It's pretty easy to do. I start off by explaining how it works and why it may or may not be worth doing. If you already understand that part, feel free to skip forward.

Shoutout to TurboAra for finding it first. More discussion in his thread:
https://f30.bimmerpost.com/forums/sh....php?t=1486773

So does the metal piece need to be drilled and put back in or just removed completely?

[sqwinny]

Thank you for this. I started driving the car hard stage 2 n20 6MT and started to get this random delayed clutch slipping when banging gears 1-2-3.

I was wondering about this but didn't know how it worked. Going to see if I can make some plans with friends to do this and open the hole slightly for improvement.

[upsidedownfunnel]

I wonder if living in California makes a difference. I know cold weather affects hydraulic fluid viscosity. When my car is warmed up, I feel like I can easily bang out shifts. I think a lot of the surging on the 1-2 shift is due to rev hang, not necessarily a slow clutch.

Your idea of using a wood screw to extract those parts is really smart though. Very easy and safe method.

[kern417]

Originally Posted by kierownik

So does the metal piece need to be drilled and put back in or just removed completely?

Removed completely

Originally Posted by sqwinny

Thank you for this. I started driving the car hard stage 2 n20 6MT and started to get this random delayed clutch slipping when banging gears 1-2-3.

I was wondering about this but didn't know how it worked. Going to see if I can make some plans with friends to do this and open the hole slightly for improvement.

It can definitely help. Our cars weren't designed for fast shifting. You also can try a clutch pedal stop so the travel isn't as long. Long clutch travel + the DME keeping the throttle open for a second can cause you to slip the clutch by mistake if you get back on the gas quickly.

Originally Posted by upsidedownfunnel

I wonder if living in California makes a difference. I know cold weather affects hydraulic fluid viscosity. When my car is warmed up, I feel like I can easily bang out shifts. I think a lot of the surging on the 1-2 shift is due to rev hang, not necessarily a slow clutch.

Your idea of using a wood screw to extract those parts is really smart though. Very easy and safe method.

Credit to pkiledj for the idea
https://f30.bimmerpost.com/forums/sh....php?t=1659392

[mspeth]

I’ve been wondering how to do this and if it was worth it thank you!

[TOMF30N55]

xDrive version here:

Shoutout Kern417 you are appreciated. I see you shouted out TurboAra above so shoutout to that human as well!