CDV seems like a really bad idea
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From: Hong Kong
Originally Posted by Penforhire,Feb 23 2009, 11:36 AM
I've had some magnificent spinning-tire launches with my CDV valve still in. I was surprised, given all the griping about CDV. I know our clutches are fundamentally weak, my AP1's slipped more, so maybe it'll slip later in life.
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From: Queen City, NC
CDV isn't the culprit, it just gets the bad rep. Someone back in 2004 noticed the car slipped more on WOT redline shifts, looked under the car, and noticed the CDV. Somehow, the CDV became the bad guy, without any real evidence to back that up. You can't see just by looking the flywheel that weighs twice as much and that was a band-aid Honda used when reworking the engine. Heavy flywheel, CDV, both tools Honda used to reduce driveline shock and all those broken diffs and spun out S2000s.
If you drive along at 4k rpm and pop the clutch on a shift, you won't notice the delay of the CDV. Same goes at 8k rpm, the only difference is the flywheel is spinning faster and the PP can't grab it properly. This doesn't mean you won't feel anything without the CDV, its removal will make the pickup feel crisper since there's nothing to dilute the shock to the drivetrain, but its not the main issue.
If you drive along at 4k rpm and pop the clutch on a shift, you won't notice the delay of the CDV. Same goes at 8k rpm, the only difference is the flywheel is spinning faster and the PP can't grab it properly. This doesn't mean you won't feel anything without the CDV, its removal will make the pickup feel crisper since there's nothing to dilute the shock to the drivetrain, but its not the main issue.
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From: La Habra
You've been on these boards long enough to know that many (most?) hard-driven AP1 S2K had clutch issues. That is certainly one reason they added the CDV in later years and probably a factor in the heavy AP2 flywheel choice (maybe less spin-down on poorly matched up-shifts?).
My AP1 led an admittedly hard life and I'm trying to make amends in my AP2. My several full-on launches in my AP2 are 1% of what my AP1 endured in the same mileage (plus it was heavily auto-x'd). Honda originally advertised sub-6-second 0-60, that's a big reason I bought it, and I was going to prove that whenever I felt like it ... all the time.
My AP1 led an admittedly hard life and I'm trying to make amends in my AP2. My several full-on launches in my AP2 are 1% of what my AP1 endured in the same mileage (plus it was heavily auto-x'd). Honda originally advertised sub-6-second 0-60, that's a big reason I bought it, and I was going to prove that whenever I felt like it ... all the time.
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From: Buffalo, NY
I removed the CDV almost 2 years ago now, and while it helps a bit, I'm inclined to agree with Saki that it isn't the entire culprit.
I still experience slippage every now and then, but it never occurs on drives around town. The only times I will notice it is on WOT redline shifts.
I'm really starting to think about upgrading the entire pp/clutch/flywheel combo as it is getting to be annoying.
I still experience slippage every now and then, but it never occurs on drives around town. The only times I will notice it is on WOT redline shifts.
I'm really starting to think about upgrading the entire pp/clutch/flywheel combo as it is getting to be annoying.
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From: Hong Kong
Originally Posted by Crazy_Schizo,Feb 24 2009, 07:54 AM
I removed the CDV almost 2 years ago now, and while it helps a bit, I'm inclined to agree with Saki that it isn't the entire culprit.
I still experience slippage every now and then, but it never occurs on drives around town. The only times I will notice it is on WOT redline shifts.
I'm really starting to think about upgrading the entire pp/clutch/flywheel combo as it is getting to be annoying.
I still experience slippage every now and then, but it never occurs on drives around town. The only times I will notice it is on WOT redline shifts.
I'm really starting to think about upgrading the entire pp/clutch/flywheel combo as it is getting to be annoying.
However, my current car (which I bought it second hand) is having some bad slipping at similar mileage. I always thought the previous owner didn't know how to drive stick properly ... never did I realize it'sa common issue among AP2s.
I know AP2s have a lighter clutch, and probably due to a weaker PP ... never thought Honda would have made such a weak clutch for this car though ...
Joined: Jul 2002
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From: Fort Lauderdale
The CDV is getting a bad rap here. Even my AP1 has had a weak pressure plate since day 1. If you do a fast 1-2 shift without letting the rpms dip, it feels like it takes a half second before 2nd gear grabs fully. It's actually faster to slow down a hair and let 2nd gear hook up at 7k rpm or so. Not a big deal to me, I'm not racing it...
I do fully intend to upgrade the pressure plate on mine whenever the clutch gets worn. But, at the rate I'm driving mine, that'll be in 2015.
I do fully intend to upgrade the pressure plate on mine whenever the clutch gets worn. But, at the rate I'm driving mine, that'll be in 2015.
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From: 727 ,Florida
Originally Posted by Saki GT,Jun 21 2008, 07:22 PM
From another thread:
Clutch slip is due to the pressure plate not having enough grip, not the cdv. People who have removed the cdv state they still experience slip, and people that have replaced the pp or put in a lighter flywheel state they have less/no slip.
I don't think the cdv is the main culprit - it slows the engagement of the clutch, but its the pp that grips. The clutch will always disengage at the same rate with a cdv, but if you've ever experienced this slippage in an AP2 on a hard shift, the slippage lasts much longer than the cdv delays the clutch. The main culprit imo is a pp that cannot grip the heavier flywheel Honda introduced in2004.
If you remove the cdv, you will have direct release that can engage faster than the cdv on shifts, and that will feel different than the cdv, but for grip, its the pp, not the cdv.
Clutch slip is due to the pressure plate not having enough grip, not the cdv. People who have removed the cdv state they still experience slip, and people that have replaced the pp or put in a lighter flywheel state they have less/no slip.
I don't think the cdv is the main culprit - it slows the engagement of the clutch, but its the pp that grips. The clutch will always disengage at the same rate with a cdv, but if you've ever experienced this slippage in an AP2 on a hard shift, the slippage lasts much longer than the cdv delays the clutch. The main culprit imo is a pp that cannot grip the heavier flywheel Honda introduced in2004.
If you remove the cdv, you will have direct release that can engage faster than the cdv on shifts, and that will feel different than the cdv, but for grip, its the pp, not the cdv.