Just another WOWWWWWHATADIFFERENCE
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Joined: Apr 2005
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Just another WOWWWWWHATADIFFERENCE
Gotta say thanks to asukadc for his '05 slave cylinder with only 2k miles on it that already had the CDV removed so I didn't have to take mine apart 
and also SIIK2NR for this incredibly helpful thread on the installation process: https://www.s2ki.com/forums/index.php?showt...tch+delay+valve
Now for you AP2 owners, I was initially skeptical of this mod. I did A LOT of research on the subject, reading countless opinions of others who have and have not done this mod, whether if it was worth the trouble or not, whether if you would feel the difference if you're not a track junkie, whether if this clutch delay "feel" is just your mind playing tricks on you.
Well, I ended up doing the mod because after a prolonged session of some spirited driving, I really started to notice the "trail lag" of clutch engagement between redline shifts. I have also felt the stock AP2 clutch took quite some travel on the pedal to engage, but I didn't think the CDV was the culprit behind this.
After swapping the slave cylinders and bleeding the clutch (I'm not the most mechanically inclined so I had some trouble with this process lol
), I refilled the brake fluid reservoir, started it up, and upon the initial reverse out of the garage, I immediately noticed something was different. The clutch engaged A HELLUVA lot sooner than before, and felt more confidence-inspiring. On the drive, the difference was even more apparent. Hard shifts did not entail the engagement delay that I had been so accustomed to. The clutch FINALLY felt like a "normal" clutch again. 
I can't believe Honda would ruin the pedal feel of this epic sports car with this cumbersome valve. 
I do kind of understand why though, for liability purposes, given our differentials aren't really our strong point to begin with.
So yes, those of you who would like your clutch to feel like a "normal" clutch, I will highly recommend this mod. It shouldn't cost you much $$ at all if you remove the CDV from your own slave cylinder. And being that I'm not the most mechanically-gifted person, I was able to pull off this install with the instructions above (thanks SIIK2NR again ).
Some comments/questions:
- I went for a fairly short drive and didn't notice any clutch slippage that some of you have reported after removing your CDV. Perhaps I'm not driving my car hard enough, but I haven't felt it yet. If I do I will certainly report back in this thread.
- Installation was fairly straightforward, but I don't understand why the OP recommended the removal of the clutch fluid line first rather than the 2 bolts. There was such an immediate and prolific flow of fluid upon removal of the line that I think it would be best for someone to remove the 2 mounting bolts FIRST, and then remove the clutch line as to prevent losing too much fluid in the brake fluid reservoir.
- Bleeding the clutch took more than the 2 tries as suggested in the thread. I'm not sure if I had let some air in the line, but the clutch didn't have any pressure feedback at all for the longest time.
Kept pumping it for what seemed like an eternity until I started to feel some pressure return. My cousin, who assisted me during this bleed process, said he heard some air release out of the drain hose for several open-valve-close-valve trials, so I guess I did get some air in it. The reservoir was really low after the fluid started flowing out of the clutch line, so I'm sure some air got into it at this point.
I did feel that I ended up bleeding it correctly...if for some chance there is still some air in the system, what kind of symptoms should I look for? Pedal pressure feels good and I didn't notice anything odd about the clutch until it starts to engage 
Some final installation notes: Definitely needs at least 2 people to do the install, unless you are an experienced mechanic. Make sure you remove the 2 bolts FIRST, and then the fluid line last so that you don't lose too much brake fluid and get air in the system. Also make sure your partner keeps an eye and refills your reservoir level when it starts to get low.
and also SIIK2NR for this incredibly helpful thread on the installation process: https://www.s2ki.com/forums/index.php?showt...tch+delay+valve
Now for you AP2 owners, I was initially skeptical of this mod. I did A LOT of research on the subject, reading countless opinions of others who have and have not done this mod, whether if it was worth the trouble or not, whether if you would feel the difference if you're not a track junkie, whether if this clutch delay "feel" is just your mind playing tricks on you.
Well, I ended up doing the mod because after a prolonged session of some spirited driving, I really started to notice the "trail lag" of clutch engagement between redline shifts. I have also felt the stock AP2 clutch took quite some travel on the pedal to engage, but I didn't think the CDV was the culprit behind this.
After swapping the slave cylinders and bleeding the clutch (I'm not the most mechanically inclined so I had some trouble with this process lol
), I refilled the brake fluid reservoir, started it up, and upon the initial reverse out of the garage, I immediately noticed something was different. The clutch engaged A HELLUVA lot sooner than before, and felt more confidence-inspiring. On the drive, the difference was even more apparent. Hard shifts did not entail the engagement delay that I had been so accustomed to. The clutch FINALLY felt like a "normal" clutch again. I can't believe Honda would ruin the pedal feel of this epic sports car with this cumbersome valve. I do kind of understand why though, for liability purposes, given our differentials aren't really our strong point to begin with. So yes, those of you who would like your clutch to feel like a "normal" clutch, I will highly recommend this mod. It shouldn't cost you much $$ at all if you remove the CDV from your own slave cylinder. And being that I'm not the most mechanically-gifted person, I was able to pull off this install with the instructions above (thanks SIIK2NR again
). Some comments/questions:
- I went for a fairly short drive and didn't notice any clutch slippage that some of you have reported after removing your CDV. Perhaps I'm not driving my car hard enough, but I haven't felt it yet. If I do I will certainly report back in this thread.
- Installation was fairly straightforward, but I don't understand why the OP recommended the removal of the clutch fluid line first rather than the 2 bolts. There was such an immediate and prolific flow of fluid upon removal of the line that I think it would be best for someone to remove the 2 mounting bolts FIRST, and then remove the clutch line as to prevent losing too much fluid in the brake fluid reservoir.
- Bleeding the clutch took more than the 2 tries as suggested in the thread. I'm not sure if I had let some air in the line, but the clutch didn't have any pressure feedback at all for the longest time.
Kept pumping it for what seemed like an eternity until I started to feel some pressure return. My cousin, who assisted me during this bleed process, said he heard some air release out of the drain hose for several open-valve-close-valve trials, so I guess I did get some air in it. The reservoir was really low after the fluid started flowing out of the clutch line, so I'm sure some air got into it at this point. I did feel that I ended up bleeding it correctly...if for some chance there is still some air in the system, what kind of symptoms should I look for?
Pedal pressure feels good and I didn't notice anything odd about the clutch until it starts to engage Some final installation notes: Definitely needs at least 2 people to do the install, unless you are an experienced mechanic. Make sure you remove the 2 bolts FIRST, and then the fluid line last so that you don't lose too much brake fluid and get air in the system. Also make sure your partner keeps an eye and refills your reservoir level when it starts to get low.
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Joined: Jun 2005
Posts: 110
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From: Chicago, IL
I know I want to do it, but I just haven't managed to get my car over to a garage to get it done. I don't have anything to lift the car, save the jack in the trunk, otherwise I'd definitely get in there and do it myself right now.