10th Gen Civic 1.5T Clutch Delay Valve Removal

[PRL Motorsports]

Hey Civic Xers, we decided to remove our CDV, or clutch delay valve, today while installing our ClutchMasters FX400 6-puck Rigid Disc Clutch and decided to document it for anyone interested in doing this nifty little mod.

What does removing the CDV do? The engineers at Honda has been putting a CDV system on many of the recent platforms to reduce drivetrain shock. The CDV allows the clutch system to simulate "slip" in an attempt to save the transmission/drivetrain. However, for racers and enthusiasts looking for more of a raw driving experience in his or her car this can be annoying. Removing the CDV greatly improves clutch engagement which in turn improves 60fts and shift times. The other cool thing is this mod costs $0 aside from a new bottle of clutch fluid needed to bleed the clutch system.

The 10th Gen's CDV assembly is identical to the 9th Gen's, so this may look familiar to some.

The CDV is located in the slave cylinder which is attached on the front of the transmission. The slave sylinder can be removed by taking out the two 12mm bolts holding it on. Next you will need a 14mm and 10mm wrench to remove the clutch line from the slave cylinder. Now the slave cylinder assembly should be able to be completely removed.

Remove the C-Clip below the bleeder valve with a pick or very tiny flathead screwdriver. This step is the biggest PITA .

Once this is out you can remove the white/black plastic CDV from the slave cylinder with the same pick/screw driver that you removed the C-Clip with.

Everything should look like this once removed.

Throw the CDV in the trash where it belongs and then carefully install the aluminum O-ringed cap back into the slave cylinder and fasten it into place with the C-Clip.

Install everything back together in the reverse order in which it was taken off. Bleed the clutch system and you are good to go!

Here are some various pictures from our clutch install!

Stock Civic Si Clutch vs ClutchMasters FX400 6-Puck

Stock Civic Si Clutch Disc

ClutchMasters FX400 6-Puck

Stock Civic Si Dual Mass Flywheel

PRL Motorsports Prototype Braided Clutch Line vs OEM Honda Clutch Line

 

[maaaaackle]

Great information man!

Edit - since it was put there to reduce drivetrain shock, are we going to see any adverse effects on the drivetrain?

i know some BMW owners do this as well...

 

[kshawn]

 

[compcrasher86]

Great information man!

Edit - since it was put there to reduce drivetrain shock, are we going to see any adverse effects on the drivetrain?

i know some BMW owners do this as well...

For what it's worth this was done very early in my BMW's life and it hasn't caused a single issue. Car has 220k on an original clutch and flywheel.

I would like to do it to my Civic but parts for this car seem cheap enough I'll just order a new slave and disect that one instead. A braided line would be a smart upgrade too because one already has to bleed the system.

 

[chokesmaster]

Could this apply to the 2.0L as well?

 

[maaaaackle]

For what it's worth this was done very early in my BMW's life and it hasn't caused a single issue. Car has 220k on an original clutch and flywheel.

I would like to do it to my Civic but parts for this car seem cheap enough I'll just order a new slave and disect that one instead. A braided line would be a smart upgrade too because one already has to bleed the system.

Is it a noticeable difference with the CDV removed?

 

[Froz3nTundra]

Was this added after the 8th gen? I thought the 10th had much smoother clutch engagement than my 8th gen.

 

[PRL Motorsports]

Great information man!

Edit - since it was put there to reduce drivetrain shock, are we going to see any adverse effects on the drivetrain?

i know some BMW owners do this as well...

With improved clutch engagement will come increased wear and tear on basically everything in the drivetrain. It's far too soon to tell with this platform, but considering this has been done for years with many other platforms, the average Joe should be fine. We don't forsee any issues unless pushing the limits of this 1.5T.

For what it's worth this was done very early in my BMW's life and it hasn't caused a single issue. Car has 220k on an original clutch and flywheel.

I would like to do it to my Civic but parts for this car seem cheap enough I'll just order a new slave and disect that one instead. A braided line would be a smart upgrade too because one already has to bleed the system.

Could this apply to the 2.0L as well?

The 2.0L may have one as well. You could probaly check by looking at the slave cylinder to see if it has a C-clip assembly like this one.

Was this added after the 8th gen? I thought the 10th had much smoother clutch engagement than my 8th gen.

The 8th Gen had one as well, very similar to this.

 

[Akalawur77]

So do all the 1.5T Civics have the CDV including the Si? I had a BMW 335i in the past and the clutch engagement was awful before I deleted the CDV on it; made a night and day difference for shifting. I don't notice that bad of an engagement on the 17 Si though like I did on the BMW

 

[compcrasher86]

Is it a noticeable difference with the CDV removed?

Yes. With the CDV would slip the clutch if you launched it and it was hard to get the 1-2 shift smooth.

Honestly I didn't notice the civic had it so it must not be too aggressive. But now I need to know what I'm missing...

 

[JDM_DOHC_SiR]

Nice!! Thank for sharing!

 

[maddmatt02]

Was just talking to a guy at work saying I wondered if I had a delay valve because it didn't seem like my pedal chard my foot up fast enough when shifting into 3rd and 4th while I was at the track. But then right maybe not because I can easily dump it and roast em in 1st and chirp 2nd pretty good... Then I get on Facebook and there it is... I'll probably wait til I do more stuff to the car though

 

[das borgen]

Damn... removing the CDV is a much easier process on Bimmers

 

[segfault]

Awesome, thanks. This was definitely on my list of to-dos.

 

[kshawn]

Just got done doing this. Already had my steal braided clutch line on. Very smooth. Going from 1st->2nd isn't boggy and my shifter feels less crunchy.

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