prove_it
Well-known member
Bigger master will move more fluid than a smaller bore. That's why a 3G eclipse brake master gives better pedal feel.
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3000gt 11/16" slave cylinder
- Thread starter tektic
- Start date
GSTwithPSI
Well-known member
Quoting tektic:
13/16 or 3/4
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
This is true. You will get less travel with a larger slave if everything in the system remains the same.
I too, have always been told shimming the pivot ball and/or extending the slave rod are "band aid" fixes, and I would agree under certain cirmstances. Much of the time, people do these two things when there is an underlying issue that needs attention, which is wrong. For example, if your clutch pedal assembly is worn, you shouldn't shim the pivot ball to correct it. In this case, shimmimg is used as a band aid fix.
In tektic's case, and as others have mentioned, sometimes shimming or extending the slave rod are necessary to get extra adjustment or travel out of a system that wasn't designed to use some of the aftermarket parts we commonly install on these cars. If you understand what's actually happening with the system, and are implementing a well thought solution, your not performing a band aid fix IMO.
Shimmimg the pivot ball does one thing, it moves the fulcrum point of the clutch fork closer to the clutch. In essence, this is performing the same function that adjusting the clutch pedal adjustment rod does. It gives you more travel by changing the point at which the clutch fork begins to move. Simply, it moves the clutch fork closer to the clutch fingers, engaging them sooner. If you understand this, and are using this to your advantage in order to compensate for travel lost because of outside factors that AREN'T underlying problems, then I don't see how that's a band aid fix.
What slave do you have in the system now (red or green)? Also, your slight leak should be of concern to you. Even a slight leak such as the one you described will cause issues. You need to fix that before really troubleshooting the system. From everything else you described, it does sound like you're going to have to take some action outside the box to correct this (e.g. shimmimg, new slave, extended push rod, etc.).
13/16 or 3/4
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
This is true. You will get less travel with a larger slave if everything in the system remains the same.
I too, have always been told shimming the pivot ball and/or extending the slave rod are "band aid" fixes, and I would agree under certain cirmstances. Much of the time, people do these two things when there is an underlying issue that needs attention, which is wrong. For example, if your clutch pedal assembly is worn, you shouldn't shim the pivot ball to correct it. In this case, shimmimg is used as a band aid fix.
In tektic's case, and as others have mentioned, sometimes shimming or extending the slave rod are necessary to get extra adjustment or travel out of a system that wasn't designed to use some of the aftermarket parts we commonly install on these cars. If you understand what's actually happening with the system, and are implementing a well thought solution, your not performing a band aid fix IMO.
Shimmimg the pivot ball does one thing, it moves the fulcrum point of the clutch fork closer to the clutch. In essence, this is performing the same function that adjusting the clutch pedal adjustment rod does. It gives you more travel by changing the point at which the clutch fork begins to move. Simply, it moves the clutch fork closer to the clutch fingers, engaging them sooner. If you understand this, and are using this to your advantage in order to compensate for travel lost because of outside factors that AREN'T underlying problems, then I don't see how that's a band aid fix.
What slave do you have in the system now (red or green)? Also, your slight leak should be of concern to you. Even a slight leak such as the one you described will cause issues. You need to fix that before really troubleshooting the system. From everything else you described, it does sound like you're going to have to take some action outside the box to correct this (e.g. shimmimg, new slave, extended push rod, etc.).
KiNgMaRtY
Well-known member
gvr4ever
Well-known member
Sorry if I missed it, but did you replace the clutch fork at any time? I can't imagine too many stock ones being around, but the stock one flexed on my with a ACT 2600 w/street disk and eventually broke. Mitsu revised the part and they are stronger now. I was able to get it working right without shimming anything, but it was still crazy heavy.
IMO, the stock setup even with everything new can handle a heavier clutch very well at all. Surprised after all this time a sure thing hasn't been engineered. I'm currently running a centerforce and it feels light as hell compared to the ACT. If I raced, I'd probably just run the 2100 and replace it more often.
IMO, the stock setup even with everything new can handle a heavier clutch very well at all. Surprised after all this time a sure thing hasn't been engineered. I'm currently running a centerforce and it feels light as hell compared to the ACT. If I raced, I'd probably just run the 2100 and replace it more often.
prove_it
Well-known member
Just to be clear, I was wondering about a larger bore MASTER cylinder.
turbowop
Well-known member
Quoting tektic:
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
That is what some guys use with a twin disk. The twins don't require as much throw from the slave, so you can use that to your advantage and use a slave with a larger bore, widening the engagement point felt at the pedal so that the clutch doesn't feel so on/off.
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
That is what some guys use with a twin disk. The twins don't require as much throw from the slave, so you can use that to your advantage and use a slave with a larger bore, widening the engagement point felt at the pedal so that the clutch doesn't feel so on/off.
tektic
Well-known member
Ah, I missed the master part of that. I agree that there should be some kind of reengineering of this whole system.
I am adressing the leaky slave with the 3kgt slave. Ever so slight it was still a problem.
I am adressing the leaky slave with the 3kgt slave. Ever so slight it was still a problem.
GSTwithPSI
Well-known member
Quoting prove_it:
Bigger master will move more fluid than a smaller bore. That's why a 3G eclipse brake master gives better pedal feel.
I definitely understand what you're saying, but I wouldn't think of it in terms of the amount of fluid being moved. The reason you have a better pedal feel with a larger master cylinder, is because a larger master cylinder increases the mechanical advantage. Simply, your leg has to do less work to exert the same amount of force on the brake system. The downfall being, your leg has to move the brake/clutch pedal farther to get the same amount of travel from whatever cylinder is being acted upon (clutch slave, brake caliper, whatever). The amount of fluid being moved is just a by-product of the system in use; that is, it's just the medium used to transfer force from one hydraulic cylinder to another. The force acting upon the fluid and the size of each cylinder is really what matters.
Remember this thread? click
Bigger master will move more fluid than a smaller bore. That's why a 3G eclipse brake master gives better pedal feel.
I definitely understand what you're saying, but I wouldn't think of it in terms of the amount of fluid being moved. The reason you have a better pedal feel with a larger master cylinder, is because a larger master cylinder increases the mechanical advantage. Simply, your leg has to do less work to exert the same amount of force on the brake system. The downfall being, your leg has to move the brake/clutch pedal farther to get the same amount of travel from whatever cylinder is being acted upon (clutch slave, brake caliper, whatever). The amount of fluid being moved is just a by-product of the system in use; that is, it's just the medium used to transfer force from one hydraulic cylinder to another. The force acting upon the fluid and the size of each cylinder is really what matters.
Remember this thread? click
prove_it
Well-known member
I do now, /ubbthreads/images/graemlins/grin.gif
Wouldn't a bigger master allow the slave to move further though? Maybe I'm just not grasping the concept.
Wouldn't a bigger master allow the slave to move further though? Maybe I'm just not grasping the concept.
prove_it
Well-known member
Ok, phew. I thought I was going crazy. lol.
slugsgomoo
Well-known member
Quoting turbowop:
Quoting tektic:
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
That is what some guys use with a twin disk. The twins don't require as much throw from the slave, so you can use that to your advantage and use a slave with a larger bore, widening the engagement point felt at the pedal so that the clutch doesn't feel so on/off.
Yeah, I removed the shim that I had in the pivot ball with the ACT 2600, run a 2g accumulator and a 2g FWD slave (also larger bore than stock, though not Isuzu sized, I didn't want to have to deal with the extra hassle). Engagement is actually quite good.
I can't imagine needing a longer rod/bigger master/smaller slave on top of shimming the pivot ball should be required with a correctly set up clutch though. I have a fidanza/CM FX400 in the talon that is fine with just a shim, though I feel like it's starting to have pedal issues /ubbthreads/images/graemlins/frown.gif
I guess the stupid question is- the clutch adjuster... how is it?
Quoting tektic:
I heard about using a q45 or Isuzu cylinder
Bigger cylinder would be less movement for same pedal throw.
That is what some guys use with a twin disk. The twins don't require as much throw from the slave, so you can use that to your advantage and use a slave with a larger bore, widening the engagement point felt at the pedal so that the clutch doesn't feel so on/off.
Yeah, I removed the shim that I had in the pivot ball with the ACT 2600, run a 2g accumulator and a 2g FWD slave (also larger bore than stock, though not Isuzu sized, I didn't want to have to deal with the extra hassle). Engagement is actually quite good.
I can't imagine needing a longer rod/bigger master/smaller slave on top of shimming the pivot ball should be required with a correctly set up clutch though. I have a fidanza/CM FX400 in the talon that is fine with just a shim, though I feel like it's starting to have pedal issues /ubbthreads/images/graemlins/frown.gif
I guess the stupid question is- the clutch adjuster... how is it?
tektic
Well-known member
I tightened it until I had no slack and the pedal was all the way up... I was never able to compress the slave by hand though. It engages at floor.
tektic
Well-known member
With the 3kgt slave and slave rod I was finally able to get my master to adjust itself. I have 2 visable threads in front of nut while adjusting the pedal from under the dash.
I used 2 m8x1.25 30mm bolts and nuts to connect the 3kgt part. I used the slave rod that came with the 3kgt slave.
Everything seems to be working as it should be. Over all impression is good. The placement of all the parts is better by ten fold! The pedal feels slightly heavier. Whatever size bore you use, I would consider using this part just for the benefits of how it fits.
Pics
I used 2 m8x1.25 30mm bolts and nuts to connect the 3kgt part. I used the slave rod that came with the 3kgt slave.
Everything seems to be working as it should be. Over all impression is good. The placement of all the parts is better by ten fold! The pedal feels slightly heavier. Whatever size bore you use, I would consider using this part just for the benefits of how it fits.
Pics
GSTwithPSI
Well-known member
Looks good! I have a bunch of questions:
How hard was bleeding it?
Can you post up the part number for that specific slave, and where did you get it?
What are your impressions after driving the car with this installed?
Were the bolts the same size, just longer?
Are you still using a stock GVR4 clutch master cylinder?
How hard was bleeding it?
Can you post up the part number for that specific slave, and where did you get it?
What are your impressions after driving the car with this installed?
Were the bolts the same size, just longer?
Are you still using a stock GVR4 clutch master cylinder?
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ade
Well-known member
Quoting Wookalar:
Jacks would know better than me seeing as how they build transmissions every day but I would suggest asking them about the pedalbox. People have found that slack in the clutch pedal is attributed to a worn bushing in the pedal assemble. Thus the slack in the system prohibits the rod from traveling far enough when the pedal is pressed. Hence the extended rod band aid fix to extend the travel.
Jnz performs the pedalbox repair. Bad news is that removing the pedalbox is a major pain in the balls.
click
I agree with the above..
John, I know repeating myself has annoyed the sh*t out of you, but I'm gonna say it one last time. its your pedals and you know that I know that you know this.
We spent all day trying to get the gt3k slave to work and it kinda works. But kinda works isn't working, is it?
Jacks would know better than me seeing as how they build transmissions every day but I would suggest asking them about the pedalbox. People have found that slack in the clutch pedal is attributed to a worn bushing in the pedal assemble. Thus the slack in the system prohibits the rod from traveling far enough when the pedal is pressed. Hence the extended rod band aid fix to extend the travel.
Jnz performs the pedalbox repair. Bad news is that removing the pedalbox is a major pain in the balls.
click
I agree with the above..
John, I know repeating myself has annoyed the sh*t out of you, but I'm gonna say it one last time. its your pedals and you know that I know that you know this.
We spent all day trying to get the gt3k slave to work and it kinda works. But kinda works isn't working, is it?
GSTwithPSI
Well-known member
So did it work or not? You guys are posting conflicting information.
tektic
Well-known member
Quoting ade:
John, I know repeating myself has annoyed the sh*t out of you, but I'm gonna say it one last time. its your pedals and you know that I know that you know this.
We spent all day trying to get the gt3k slave to work and it kinda works. But kinda works isn't working, is it?
NO play is seen in my pedal assembly. Just because that was the problem in your car doesn't me it is the problem with everyone's car. When the clutch pedal is depress the master is fully depressed for the same throw with no slack or give in any which way what so ever. With no explanation as to why it is an issue and without a plan in place as to how to readjust it had we removed it, I don't see cutting and rewelding my pedal assembly on a whim a sensible repair.
With that said, the way it's set up now the hydrolic system is self adjusting properly like never before. I drove the car for over an hour to test it and it works, however the pedal is still at the floor and is still some drag from the clutch, most realized when shifting in reverse with a clunk or grind. The original post which gave me the idea said that the stock slave rod was used. I'm currently using the 3kgt rod. In the post above you can see the length difference between the two rods is very drastic. I don't feel that the stock rod is necessary and will probably make a sheet metal shim for slave cylinder instead. The clutch fork is well into the right side of the window when clutch is at rest. I don't remember it being like this when I installed the clutch, but that's where it is now.
Quoting GSTwithPSI:
Looks good! I have a bunch of questions:
How hard was bleeding it?
Can you post up the part number for that specific slave, and where did you get it?
What are your impressions after driving the car with this installed?
Were the bolts the same size, just longer?
Are you still using a stock GVR4 clutch master cylinder?
-Bleeding the slave was 100 times easier than the stock configured unit.
-It's a slave from a 96+ 3kgt vr4 w 11/16 bore (MB670290) I got this part number (072-8865) but couldn't confirm the bore so I bought a doorman part CS360006 that explicitly said the bore size. it turned out to be an aisin part in the box.
-Impression It's heavier and gives more throw just like expected. The fit is better than the stock unit. The hydrolic system still has gremlins but this part seems to be doing it's job well.
-The 3kgt slave is not threaded like stock. It also mounts on the opposite side of the trans case (between fork and case). A nut and bolt is needed as no threads are present. I used the stock size bolts (m8x1.25) but 30mm long with a matching nut. I could have gotten away with 25mm but the hardware store only had one. If I do shim between case and slave the 30mm bolts will turn out advantageous.
-I'm using an EXEDY Part # MC179 I have no idea the bore. furthermore I did not bench bled it and suspect there may be some air trapped in it.
John, I know repeating myself has annoyed the sh*t out of you, but I'm gonna say it one last time. its your pedals and you know that I know that you know this.
We spent all day trying to get the gt3k slave to work and it kinda works. But kinda works isn't working, is it?
NO play is seen in my pedal assembly. Just because that was the problem in your car doesn't me it is the problem with everyone's car. When the clutch pedal is depress the master is fully depressed for the same throw with no slack or give in any which way what so ever. With no explanation as to why it is an issue and without a plan in place as to how to readjust it had we removed it, I don't see cutting and rewelding my pedal assembly on a whim a sensible repair.
With that said, the way it's set up now the hydrolic system is self adjusting properly like never before. I drove the car for over an hour to test it and it works, however the pedal is still at the floor and is still some drag from the clutch, most realized when shifting in reverse with a clunk or grind. The original post which gave me the idea said that the stock slave rod was used. I'm currently using the 3kgt rod. In the post above you can see the length difference between the two rods is very drastic. I don't feel that the stock rod is necessary and will probably make a sheet metal shim for slave cylinder instead. The clutch fork is well into the right side of the window when clutch is at rest. I don't remember it being like this when I installed the clutch, but that's where it is now.
Quoting GSTwithPSI:
Looks good! I have a bunch of questions:
How hard was bleeding it?
Can you post up the part number for that specific slave, and where did you get it?
What are your impressions after driving the car with this installed?
Were the bolts the same size, just longer?
Are you still using a stock GVR4 clutch master cylinder?
-Bleeding the slave was 100 times easier than the stock configured unit.
-It's a slave from a 96+ 3kgt vr4 w 11/16 bore (MB670290) I got this part number (072-8865) but couldn't confirm the bore so I bought a doorman part CS360006 that explicitly said the bore size. it turned out to be an aisin part in the box.
-Impression It's heavier and gives more throw just like expected. The fit is better than the stock unit. The hydrolic system still has gremlins but this part seems to be doing it's job well.
-The 3kgt slave is not threaded like stock. It also mounts on the opposite side of the trans case (between fork and case). A nut and bolt is needed as no threads are present. I used the stock size bolts (m8x1.25) but 30mm long with a matching nut. I could have gotten away with 25mm but the hardware store only had one. If I do shim between case and slave the 30mm bolts will turn out advantageous.
-I'm using an EXEDY Part # MC179 I have no idea the bore. furthermore I did not bench bled it and suspect there may be some air trapped in it.
ade
Well-known member
i would agree with you if your pedal was never a problem, but it started as the problem and had to be welded. i had the same symptoms for months, pulled and shimmed the trans! outside! during a blizzard! replaced the master and slave three times! my first and second weld on the pedal showed no play either, so if the third weld did not give and break on me while bleeding it would have been a few more months of me being as stubborn ass you are.
you want a plan? well i cant give you one. i don't remember where i set it on the 4th weld, lucky i chose out back at Colvins to replace both master and slave for the third time when the pedal broke. i didn't want to touch it i was so frustrated. But i did and walked into the shop soaked to the skin freezing. Jimmy chuckled took if from me and asked where, i looked at & set it set it. he welded, i reinstalled and praise be to google! it worked! not kinda work like it did every time i bled a bit, replaced a bit or adjusted a bit more.
i couldnt believe it could go into gear so smooth. no notchy feeling, no fighting to get into gear, no grinding like it did, which yours is doing now.... whatever i don't have to explain myself, you were there or updated the whole time. poor poor synchros.
you want a plan? well i cant give you one. i don't remember where i set it on the 4th weld, lucky i chose out back at Colvins to replace both master and slave for the third time when the pedal broke. i didn't want to touch it i was so frustrated. But i did and walked into the shop soaked to the skin freezing. Jimmy chuckled took if from me and asked where, i looked at & set it set it. he welded, i reinstalled and praise be to google! it worked! not kinda work like it did every time i bled a bit, replaced a bit or adjusted a bit more.
i couldnt believe it could go into gear so smooth. no notchy feeling, no fighting to get into gear, no grinding like it did, which yours is doing now.... whatever i don't have to explain myself, you were there or updated the whole time. poor poor synchros.
GSTwithPSI
Well-known member
I'm not quite following the personal quarrel between you two, but checking to see if the pedal assembly is worn isn't rocket science. I've personally experienced problems with the clutch pedal assembly. I rebuilt the pedal box in 1813 and it was a horrible pain in the ass. It's not hard to tell if the pedal assembly is worn. For the most part, you can just feel it. You can also see it visually if you take a peek under the dash and move the pedal arm with your hand. I'm not sure what all the fuss is about. Either the pedal is good, or it isn't. Which is it?
tektic
Well-known member
Ade... If you want to debate nonsense fine. make your own thread. What does you pulling your trany during a blizzard have to do with my slave cylinder?
Theres no evidence of movement in my pedal as stated... Not rocket science. There is no fatigue in the weld. If I were to change where it is now i would have to know where I wanted it to go. Since I don't I wil use what I have until it works. When I have the time.I have 2 other cars and more than one other issue keeping me from driving this one more regularly.
Theres no evidence of movement in my pedal as stated... Not rocket science. There is no fatigue in the weld. If I were to change where it is now i would have to know where I wanted it to go. Since I don't I wil use what I have until it works. When I have the time.I have 2 other cars and more than one other issue keeping me from driving this one more regularly.
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