If you have a 6 Speed MT and HATE the shifting: READ ME
08-02-2009, 05:40 PM
#41
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I did the mod the other night. It was quick. To all you guys thinking of spending $60-$70 on buying another slave, save your money (or send it to me) cause you'll be done in no time. I feel a little more grab all the time and if I stomp on it, a lot more. No slipping. If you don't beat the car all the time, but want better clutch control, do it. I changed my clutch fluid out while I was at it. That s**t was nasty!
Thanks Opel and Rockstar!
Thanks Opel and Rockstar!
Last edited by Deadgame28; 08-02-2009 at 05:44 PM.
08-02-2009, 08:14 PM
#43
what an amazing find. i test drive a 6MT about a year ago in an attempt to do a trade-in with my current 5AT, and i loved it, except for the freaking clutch engagement, it felt like mush.
i asked the sales guy about it, and he said they all did that, even his newer civic. at that point i knew that i wouldn't be happy with that clutch.
if this mod doesn't harm the mounts/engine longterm via the loss of the torque absorption, this would be great!
i asked the sales guy about it, and he said they all did that, even his newer civic. at that point i knew that i wouldn't be happy with that clutch.
if this mod doesn't harm the mounts/engine longterm via the loss of the torque absorption, this would be great!
08-02-2009, 10:07 PM
#44
Thanks all...
I don't know it all but what I read prior to doing this was that this delay was actually the reason the clutch can go prematurely. Today, after a few days of driving like this I can tell you that I would have a hard time going back. This is what every other stick shift I've ever owned/driven felt like.
Again though...I am NOT constantly redlining or pounding on this car. I mean, I love to occasionally hit it...but I drive chill most of the time. The improvement in response feeling etc...is worth it to me. That being said, I hope to not cause any harm or have steered anyone to do this if this does end up causing drivetrain issues.
I don't know it all but what I read prior to doing this was that this delay was actually the reason the clutch can go prematurely. Today, after a few days of driving like this I can tell you that I would have a hard time going back. This is what every other stick shift I've ever owned/driven felt like.
Again though...I am NOT constantly redlining or pounding on this car. I mean, I love to occasionally hit it...but I drive chill most of the time. The improvement in response feeling etc...is worth it to me. That being said, I hope to not cause any harm or have steered anyone to do this if this does end up causing drivetrain issues.
08-03-2009, 05:13 AM
#45
Registered Member
A neighbor of mine across the street was doing some maintenance on his BMW and noticed that the line from the delay valve to the clutch was full of air! Now he knew why his car was so hard to get into gear at times (he bought it used). He removed the delay valve, purged and filled his clutch fluid. He came over to borrow my 36mm socket for his oil change and that is how I found out about his discovery.
08-03-2009, 05:20 AM
#46
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This is what a non-restrictor valve clutch disc looks like.
The springs that the restrictor valve replaced are designed to soak up the shock of a fast high torque clutch engagement.
The 6MT in the TL is not all that strong & the system had to be de-tuned to handle the small amount of increased torque in the Type S.
The 2010 6MT is a new stronger design because the existing box could not handle the 305HP motor.
The springs that the restrictor valve replaced are designed to soak up the shock of a fast high torque clutch engagement.
The 6MT in the TL is not all that strong & the system had to be de-tuned to handle the small amount of increased torque in the Type S.
The 2010 6MT is a new stronger design because the existing box could not handle the 305HP motor.
The springs in the center hub of a friction disk are there for two reasons. 1) To reduce clutch chatter, and 2) To reduce drive train shock. Without them, engine torque is directly transmitted to the transmission input shaft with no dampening other than that applied by the operator in the form of slippage. If people do this mod, they should be aware of these things and take it easy on their trannies. As long as the valve is working as designed, your shifts and clutch operation will also be fine. When the valve starts to fail, have it serviced immediately.
Incidently, the clutch delay value will not reduce clutch chatter which is why you may experience this from time to time, especially after your car has sat during a rain or high humidity weather. This should go away quickly.
08-03-2009, 08:01 AM
#47
^^^This post makes me feel a little better about having done this modification. Thanks for the extra knowledge and heads up. I'll definitely keep it in mind and will never powershift seeing as how I don't race or anything.
J.
J.
08-04-2009, 12:34 AM
#50
slave cyclinder
I have a 08 TL type S, is my slave cyclinder the same as the base TL's slave cyclinder??? I'm really sick of my clutch and the way my car shifts, I'm really considering to remove the check valve.
08-04-2009, 12:38 AM
#51
Base TL does not have a slave cylinder cause it's Automatic... 
If you mean the earlier 04-06 TL sport 6MT, then yes I would imagine it is the same slave cylinder. You can cross reference part numbers for yourself to be sure at sites like www.AcuraOEMParts.com...
If you mean the earlier 04-06 TL sport 6MT, then yes I would imagine it is the same slave cylinder. You can cross reference part numbers for yourself to be sure at sites like www.AcuraOEMParts.com...
08-04-2009, 06:57 AM
#53
^^^please note that others have had success with removing the o-ring without cutting anything. I personally struggled for almost an hour with all the tools I had to try and get that ring out so I came up with the dremel idea. You could probably even put that cut in there with a hacksaw since the metal was pretty soft. Just don't go nuts and make sure you're cutting where the ring's opening is so you don't cut the ring itself...otherwise you'll have to find another one to use!
08-04-2009, 07:41 AM
#54
Ryan Christopher
This is what a non-restrictor valve clutch disc looks like.
The springs that the restrictor valve replaced are designed to soak up the shock of a fast high torque clutch engagement.
The 6MT in the TL is not all that strong & the system had to be de-tuned to handle the small amount of increased torque in the Type S.
The 2010 6MT is a new stronger design because the existing box could not handle the 305HP motor.
The springs that the restrictor valve replaced are designed to soak up the shock of a fast high torque clutch engagement.
The 6MT in the TL is not all that strong & the system had to be de-tuned to handle the small amount of increased torque in the Type S.
The 2010 6MT is a new stronger design because the existing box could not handle the 305HP motor.
So it would also reduce the impact on the transmission during clutch engagement.
08-04-2009, 08:11 AM
#56
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I put a new SC in the vice and had it apart in 10 minutes once I found a pick that work. Surprisingly a point strait one worked instead of all the crooked ones, and it worked better on one side of the ring than the other. Might try a nail if you dont have a pick?? Be sure to put the cap on the right way! Its difficult to remove if it is accidentally put in upside down, plus you have to take the ring out again (don't ask!!)
ML
ML
08-04-2009, 09:39 AM
#58
if you think the reading was interesting...wait till you do this modification. I was still feeling it out but as the days go on and I've driven my car more...i can tell you this makes all the difference.
08-04-2009, 03:25 PM
#61
Well now that we've covered the technical side of the check-valve slave cylinder, and the dual-mass flywheel, what is the self adjusting pressure plate I've been hearing about?
Last edited by 94eg!; 08-04-2009 at 03:28 PM.
08-05-2009, 05:02 AM
#62
Registered Member
A powershift is a very fast shift performed without raising you foot from the throttle when you disengage the clutch. In other words, once you go WOT in the race, your throttle stays planted to the floor during every shift and you do use your clutch for the shifts. As you can imagine a lot is going on during this process that can wreak havoc on a drive train. The American supercars of the mid 60's could take this kind of abuse as they were made of much stronger stuff. I would not bet my TL would last long doing this.
08-05-2009, 07:58 AM
#63
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Quick question before I put my new SC in hopefully this weekend. Is the rod that hooks up to the fork supposed to loose from the cylinder? I pulled back the boot and the whole assembly comes off. the rod just sits in the "bucket" of the piston and can move all over the place. At first I thought it was a cable but this didn't make sense so that's why I check it out. Is this correct?
ML
ML
08-05-2009, 06:23 PM
#67
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I forgot to respond to this. You do NOT want to powershift a manual TL anyway, regardless of this mod or not. Powershifting a FWD car could really put the craps to the drive train. Just so we're on the same wave length here.
A powershift is a very fast shift performed without raising you foot from the throttle when you disengage the clutch. In other words, once you go WOT in the race, your throttle stays planted to the floor during every shift and you do use your clutch for the shifts. As you can imagine a lot is going on during this process that can wreak havoc on a drive train. The American supercars of the mid 60's could take this kind of abuse as they were made of much stronger stuff. I would not bet my TL would last long doing this.
A powershift is a very fast shift performed without raising you foot from the throttle when you disengage the clutch. In other words, once you go WOT in the race, your throttle stays planted to the floor during every shift and you do use your clutch for the shifts. As you can imagine a lot is going on during this process that can wreak havoc on a drive train. The American supercars of the mid 60's could take this kind of abuse as they were made of much stronger stuff. I would not bet my TL would last long doing this.
This is not the stuff of the TL 6MT. You can shift it pretty fast but you are stupid to bang it
08-05-2009, 06:43 PM
#68
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Please correct me if I am wrong, but it seems to me that they are using the dual mass flywheel to do this rather then the friction plate. The whole purpose of the flywheel is to absorb the shock and vibration transmitted to the drive train. The flywheels are mainly used on diesel applications to smooth out the tq spikes created by the diesel engine.
So it would also reduce the impact on the transmission during clutch engagement.
So it would also reduce the impact on the transmission during clutch engagement.
The over torque friction release if it gets overloaded slips instead of letting the spring #3 take a hit.
If the friction release gets hit too often it burns up & the spring breaks.
That's why the 6MT clutch has a restrictor valve to prevent the friction release from getting overworked & failing.
08-05-2009, 07:10 PM
#69
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To reduce drivetrain shock and limit the torque load on transmission components, the clutch includes a one-way delay valve located in the slave cylinder that restricts return fluid flow during rapid clutch engagement. This makes the clutch engagement more gradual during rapid release.(http://corporate.honda.com/press/article.aspx?id=4215)
08-05-2009, 07:38 PM
#70
^^^I could understand that that may have been the intention for it...but it doesn't take into account the crappy feel of the clutch when driving the car normally and NOT being rough on it, which in my case accounts for 98% of my driving. Why was this not needed on other racier cars like the RSX etc. It was not a good call IMO...make the car drive like crap all the time so that you can protect it in case you start driving it too hard. It's a CYA move and it sucks and doesn't apply to everyone.
08-05-2009, 08:16 PM
#71
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[QUOTE=rockstar143;11178618 Why was this not needed on other racier cars like the RSX etc.[/QUOTE]
Most likely the torque developed by the motor was not sufficient to require it.
When a transmission is designed its developed to work with specific workload (torque) parameters. The thickness of the case, size of shafts, gears etc are all built to this spec. This lets then get decent weight, reliability out of the box & importantly cost to the consumer.
Like anything else in life there is mission creep.
The motors get a little more powerful, then a little more powerful again till the new great engine, in this case the TypeS finally eats up all the excess capacity in the box so it needs band aids to survive like restrictor valves & software that limits power in 1st & 2nd gear etc.
Eventually they build a new box, like they did for the 4G TL at the cost of tens of millions of dollars in development money & new tooling. That being said sometime down the road the new 6MT box will also get some band aids as the engines get more powerful.
Most likely the torque developed by the motor was not sufficient to require it.
When a transmission is designed its developed to work with specific workload (torque) parameters. The thickness of the case, size of shafts, gears etc are all built to this spec. This lets then get decent weight, reliability out of the box & importantly cost to the consumer.
Like anything else in life there is mission creep.
The motors get a little more powerful, then a little more powerful again till the new great engine, in this case the TypeS finally eats up all the excess capacity in the box so it needs band aids to survive like restrictor valves & software that limits power in 1st & 2nd gear etc.
Eventually they build a new box, like they did for the 4G TL at the cost of tens of millions of dollars in development money & new tooling. That being said sometime down the road the new 6MT box will also get some band aids as the engines get more powerful.
08-05-2009, 08:55 PM
#72
I would disagree. I don't think the gearbox has any trouble handling the torque.
They are put in place because the vehicle is an overpowered FWD. There is only so much torque you can put to the ground on takeoff w/ FWD. Especially when it comes to a heavy car w/ relatively soft luxury/sport suspension...
Just my opinion...
They are put in place because the vehicle is an overpowered FWD. There is only so much torque you can put to the ground on takeoff w/ FWD. Especially when it comes to a heavy car w/ relatively soft luxury/sport suspension...
Just my opinion...
08-05-2009, 11:38 PM
#73
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I would disagree. I don't think the gearbox has any trouble handling the torque.
They are put in place because the vehicle is an overpowered FWD. There is only so much torque you can put to the ground on takeoff w/ FWD. Especially when it comes to a heavy car w/ relatively soft luxury/sport suspension...
Just my opinion...
They are put in place because the vehicle is an overpowered FWD. There is only so much torque you can put to the ground on takeoff w/ FWD. Especially when it comes to a heavy car w/ relatively soft luxury/sport suspension...
Just my opinion...
BTW the 6 MT series in my car has been shelling 3rd gear syncro's so frequently they finally had to put out a TSB on it to do a free trans rebuild for units with problems.
Had mine done & there was a big improvement in drivability when you were shifting quickly
This was after denying there was a problem with the 6MT for about 5 years
08-06-2009, 12:49 AM
#74
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Don't know if the same issue will come up on the TL, but...
I own an '04 S2K and strongly considered removing the delay valve on the slave cylinder. But, others have done the mod and realized it just moves the problem.
In the case of the S2K, the flywheel mass is sufficient that significant slipping still occurs on rapid shifts due to the flywheel mass. Some have gone to a lighter weight flywheel. Apparently Honda moved to a slightly heavier flywheel in AP2, and some speculate that this keeps the engine coasting in the powerband...especially during a 1-2 shift (otherwise, you drop out of VTEC since you arrive in 2d gear at below 6K).
I'd be hesitant to do the mod for fear of trashing the engine mounts or otherwise damaging the driveline w/ shock. As others have noted, if you don't dump the clutch it probably won't hurt and may improve the response. Please give feedback if it continues to slip...that may give some insight as to how the TL flywheel design behaves.
Oh, and btw - had the 3d gearset replaced (w/ new synchro) and shifting anomalies have disappeared. I have no complaints.
I own an '04 S2K and strongly considered removing the delay valve on the slave cylinder. But, others have done the mod and realized it just moves the problem.
In the case of the S2K, the flywheel mass is sufficient that significant slipping still occurs on rapid shifts due to the flywheel mass. Some have gone to a lighter weight flywheel. Apparently Honda moved to a slightly heavier flywheel in AP2, and some speculate that this keeps the engine coasting in the powerband...especially during a 1-2 shift (otherwise, you drop out of VTEC since you arrive in 2d gear at below 6K).
I'd be hesitant to do the mod for fear of trashing the engine mounts or otherwise damaging the driveline w/ shock. As others have noted, if you don't dump the clutch it probably won't hurt and may improve the response. Please give feedback if it continues to slip...that may give some insight as to how the TL flywheel design behaves.
Oh, and btw - had the 3d gearset replaced (w/ new synchro) and shifting anomalies have disappeared. I have no complaints.
08-06-2009, 12:54 AM
#75
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08-06-2009, 05:12 AM
#76
Registered Member
Also the 4MT's used in pure drag racing stock classes had every other tooth (dog) in the dog collar assemblies ground down to aid the shift which could be made without using the clutch.
This is not the stuff of the TL 6MT. You can shift it pretty fast but you are stupid to bang it
This is not the stuff of the TL 6MT. You can shift it pretty fast but you are stupid to bang it
For everyone else here, what BEAR is describing is (was?) called "bang shifting". This was a technique whereby the driver performed shifts without using the clutch AND with his foot in the throttle the whole time. When BEAR talks about removing dog teeth, this was done to machines that were not street use cars.
Incidently, I believe it was the teeth arrayed around the outside of the synchronizers which insert into their corresponding blocker ring "tabs" that were alternately removed. I remember a friend doing this to a Muncie 4-speed from a GTO he was setting up for the track.
08-06-2009, 05:27 AM
#77
Registered Member
Just for clarification purposes, here are some definitions of shifting techniques.
o Speed shifting - Normal shifting done very, very fast.
o Power shifting - Speed shifting but staying in the throttle the entire time.
o Bang shifting - Power shifting but not using the clutch between shifts.
I always speed shifted. Power shifting, though common for street driven supercars of the time, was something I didn't wish to do because of the potential of damage to my street machine. Besides, I had perfected my speed shifting technique with my car. I love my Inland Steel shifter and it work perfectly with my technique. Here are some pictures of someone' '66 396 Chevelle interior which is identical to what mine looked like. Notice the infamous "knee-knocker" tach which I came to like, too.
http://mysterychevelle.homestead.com/interior.html
o Speed shifting - Normal shifting done very, very fast.
o Power shifting - Speed shifting but staying in the throttle the entire time.
o Bang shifting - Power shifting but not using the clutch between shifts.
I always speed shifted. Power shifting, though common for street driven supercars of the time, was something I didn't wish to do because of the potential of damage to my street machine. Besides, I had perfected my speed shifting technique with my car. I love my Inland Steel shifter and it work perfectly with my technique. Here are some pictures of someone' '66 396 Chevelle interior which is identical to what mine looked like. Notice the infamous "knee-knocker" tach which I came to like, too.
http://mysterychevelle.homestead.com/interior.html
08-06-2009, 10:16 AM
#80
Ryan Christopher
A dual mass flywheel is a vibration damper not an over torque absorber. The spring has a release mechanism built in to release it if it gets hit too hard (fast shift - quick clutch dump) which is #4 in your picture
The over torque friction release if it gets overloaded slips instead of letting the spring #3 take a hit.
If the friction release gets hit too often it burns up & the spring breaks.
That's why the 6MT clutch has a restrictor valve to prevent the friction release from getting overworked & failing.
The over torque friction release if it gets overloaded slips instead of letting the spring #3 take a hit.
If the friction release gets hit too often it burns up & the spring breaks.
That's why the 6MT clutch has a restrictor valve to prevent the friction release from getting overworked & failing.
Many clutch discs have a spring-loaded center hub for this very purpose. The springs provide a little "give" when the clutch is engaged, and also help dampen harmonics and subtle variations in the engine's power output.
DUAL MASS FLYWHEELS
Taking this concept a step further, some vehicles use a second set of springs in a two-piece "dual mass" flywheel for essentially the same purpose. A dual mass flywheel has a series of springs mounted sideways between the primary and secondary flywheels. This provides extra vibration dampening and eliminates excessive transmission gear rattle for smoother clutch engagement and operation.
Dual mass flywheels were first used in 1987 on Chevrolet, Ford and GMC diesel-powered light trucks, and are found today on a number of trucks and even some European sports and luxury cars.
Dual mass flywheels can be expensive to replace. Because of this, some aftermarket suppliers have come out with conventional one-piece solid flywheels that can be installed in place of an original equipment dual mass flywheel. A solid flywheel can save you some money, but the trade-off may be increased drivetrain harshness and vibration.
Some OEMs caution against replacing a dual mass flywheel with a solid flywheel because it may contribute to premature transmission failure (due to increased shock loading of the gears)."
Found Here
It looks like the valve that is in the Slave cylinder was put there to increase the amount of "slippage" that occurs, but the DM flywheel is still helping in the absorption as well. So as long as you actually drive the car correctly and are not popping the clutch all the time, this should hold up fine. Even with the occasional hard shift from 1-2 or 2-3, you should not see any additional wear.
Most of drive the car normally and enjoy the feeling of driving a manual transmission car, but this feature that Honda added was done so for those that wanted manual, but have never really driven one.
I guess time will tell. With more and more people doing this mod, we will see if it really affects the transmission. Opel has been running his this way with a supercharger for more then 2 years and has not had any issue with it. This is far more abusive then those of us who are N/A with a few bolt ons.
I agree that the transmission is approaching its threshold for power, but as with everything Honda does, I am sure there is still a good buffer in there (25%-30%) beyond what the factory power is.
So far Pass has had good luck with his transmission in the turboed TL and he has doubled the tq.
For those that would worry or don't have a ton of experience driving a manual transmission car, I would say not to do this. But for those that really enjoy the feel of the direct engagement of a manual car and have plenty of experience driving a manual, this is for you!
This is a mod that the owner assumes full responsibility for what they are doing, those that have suggested and given DIY help for doing this, assume no responsibility if damage were to occur to a vehicle. This is a fairly new mod for our TL community and there are very few long term reliability tests.
As the car gains more aftermarket support (i.e. - clutches), they may produce a solid flywheel to replace the DMF and a spring-loaded center hub disc for the solid disc currently in the car.
For all those that have done this, continue to keep everyone posted on driving experiences you have - good, bad or ugly. Personally I hate the way it currently engages and can not wait to get the time to actually do mine.
Sorry for the long post. Just wanted to try and clear some things up.