Drill Mod Question (Three Restrictions?)
Thread Starter
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
Drill Mod Question (Three Restrictions?)
I just got my slave in and already removed the roll pin and drilled out the restriction in the hose where the hose inserts into the slave unit. I know when I do the clutch there is another restriction in the line that connects to the CMC about 1 inch down the hose from the CMC but I have heard rumor of another restriction inside the 90 degree turn of the slave hose. Is this true? If so it would seem impossible to get to!
[Modified by 5 Liter Eater, 8:26 PM 5/16/2004]
[Modified by 5 Liter Eater, 8:27 PM 5/16/2004]
[Modified by 5 Liter Eater, 8:26 PM 5/16/2004]
[Modified by 5 Liter Eater, 8:27 PM 5/16/2004]
Drifting
Joined: Jul 2002
Posts: 1,320
Likes: 0
From: Duncanville Texas
Re: Drill Mod Question (5 Liter Eater)
That is the whole problem......:) (no pun intended)
Because our master cylinders are not like the F-body CMC we cannot drill the line where the restriction would be:( (on the other side of the 90 degree bend)
Because our master cylinders are not like the F-body CMC we cannot drill the line where the restriction would be:( (on the other side of the 90 degree bend)
Le Mans Master
Joined: Oct 2003
Posts: 6,126
Likes: 19
From: Streamwood illinois
Re: Drill Mod Question (z0sense)
has anyone ever found out if the drill mod would definately fix a sticking pedal? I remember reading of someone doing this and it not curing the problem.
Dave
Dave
Drifting
Joined: Jul 2002
Posts: 1,320
Likes: 0
From: Duncanville Texas
Re: Drill Mod Question (TT_Vert)
It really does not cure the problem. Apparently the problem lies in 3 things: Master Cylinder, Slave Cylinder, Pressure Plate........
I replaced my factory clutch with an aftermarket one and had no problems (keeping the same hydralics unmodified). I did have the sticking clutch pedal until then.
I replaced my factory clutch with an aftermarket one and had no problems (keeping the same hydralics unmodified). I did have the sticking clutch pedal until then.
Le Mans Master
Joined: Oct 2003
Posts: 6,126
Likes: 19
From: Streamwood illinois
Re: Drill Mod Question (z0sense)
so its primarily the clutch itself then? Thats gonna suck. I was hoping to bleed the clutch and be ok. The car only has 22k miles on it. I dunno why mine would start happening right after the LT install :(
Dave
Dave
Drifting
Joined: Jul 2002
Posts: 1,320
Likes: 0
From: Duncanville Texas
Re: Drill Mod Question (TT_Vert)
Not sure either. I do know that the line that runs to the slave is right next to the header. The heat may have something to do with it.
I would definitely try to bleed it first. ALot of people have had good luck with it. (although they do say it comes back:))
I had my clutch sticking issue from the factory with 12K miles. Also it is this the first time you have shifted the car hard? It may have always been there.
I would definitely try to bleed it first. ALot of people have had good luck with it. (although they do say it comes back:))
I had my clutch sticking issue from the factory with 12K miles. Also it is this the first time you have shifted the car hard? It may have always been there.
Le Mans Master
Joined: Oct 2003
Posts: 6,126
Likes: 19
From: Streamwood illinois
Re: Drill Mod Question (z0sense)
no its happened at the track when it was stock. But it only happened 1 out of 4 runs. Now it happens every time at the track on the 3 to 4 shift at the track even if i let it cool down. If I recall the clutch braided line isnt that close to the header. maybe ill get some type of wrap for the line and see what it does
Dave
Dave
Melting Slicks
Joined: Jan 2001
Posts: 2,635
Likes: 2
From: Aloha, Oregon
Re: Drill Mod Question (z0sense)
That is the whole problem......:) (no pun intended)
Because our master cylinders are not like the F-body CMC we cannot drill the line where the restriction would be:( (on the other side of the 90 degree bend)
Because our master cylinders are not like the F-body CMC we cannot drill the line where the restriction would be:( (on the other side of the 90 degree bend)
I am still running this same clutch mod setup; I have never had a sticking pedal since, nor has the cap leaked.
Robert
http://www.gen3motorsports.com
[Modified by rwj383, 11:21 PM 5/16/2004]
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
Re: Drill Mod Question (rwj383)
The 3rd restriction CAN be eliminated. I did a write-up on it a couple years ago: http://forums.corvetteforum.com/zerothread?id=323904 At the 90 degree bend you simply drill through the outer casing on though down the restricted line, then JB weld a threaded cap onto the case to close it back up.
I am still running this same clutch mod setup; I have never had a sticking pedal since, nor has the cap leaked.
Robert
I am still running this same clutch mod setup; I have never had a sticking pedal since, nor has the cap leaked.
Robert
Thanks again!
Melting Slicks
Joined: Jan 2001
Posts: 2,635
Likes: 2
From: Aloha, Oregon
Re: Drill Mod Question (5 Liter Eater)
Thanks for that Robert! That 90 degree blockage is definitely easier to get to than the 90 degree bend in the slave's hose. So there is the slave's hose end and the CMC's hose end inside the far side of the 90 degree block but I'm a little confused about this other blockage halfway down the CMC hose that you get around by cutting it and rejoining it with flare unions. Where is there more info on this?
Thanks again!
Thanks again!
robert
Thread Starter
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
Re: Drill Mod Question (rwj383)
PM'ed you RE: the parts. I'm curious if you note a definite difference with all the restrictions removed. Certainly the pedal does not stick anymore right? Does the clutch engage harder/quicker?
Burning Brakes
Joined: Jun 2002
Posts: 1,037
Likes: 31
From: Richmond Texas
Re: Drill Mod Question (5 Liter Eater)
This is an interesting discussion. Dad's is a little to spongy for my taste. His has only stuck a couple of times. My main issue is the slow return. I'm used to clutches hitting hard and fast. No delay. If this mod fixes this, then awesome.
Le Mans Master
Joined: Oct 2003
Posts: 6,126
Likes: 19
From: Streamwood illinois
Re: Drill Mod Question (5 Liter Eater)
I went and got a mighty vac and bled the system. its a little better (im not sure i got all the air out)> it no longer will grind into 4th but sometimes it'll stick. One difference is before when the pedal went the to floor, no matter how hard i pressed it, the clutch was engaged. NOW, i have about 1" of travel and that inch will disengage the clutch..
Anyone wanna take a stab at that?? :D
Dave
Anyone wanna take a stab at that?? :D
Dave
Team Owner
Joined: Apr 2001
Posts: 36,453
Likes: 2
From: Overwhelmed as one would be, placed in my position.... DFW, TX
St. Jude Donor '05
Re: Drill Mod Question (TT_Vert)
Ok, here's a dumb question- why don't you just replace the whole line? It can't be that unique, can it?
Melting Slicks
Joined: Jan 2001
Posts: 2,635
Likes: 2
From: Aloha, Oregon
Re: Drill Mod Question (Umrswimr)
Ok, here's a dumb question- why don't you just replace the whole line? It can't be that unique, can it?
Once i removed these 3 restrictions, I never had a failed peddle again. however, foot effort was increased. But since I have an adjustable master cyl I can tune the foot effort.
robert
Team Owner
Joined: Apr 2001
Posts: 36,453
Likes: 2
From: Overwhelmed as one would be, placed in my position.... DFW, TX
St. Jude Donor '05
Re: Drill Mod Question (rwj383)
you certainly could modify the entire line from the outlet of the master all the way down to the inlet of the slave. not a bad idea but then youd be removing that quick disconnect in the middle of the line that really aids in the R&R of the drivetrain.
robert
robert
I just don't know if it's worth the effort to take the line out and hassle with drilling it in three spots... :confused:
Race Director
Joined: Mar 2001
Posts: 19,965
Likes: 6,770
From: Bonneville Salt Flats
Re: Drill Mod Question (5 Liter Eater)
Yes, heat in the system can definitely worsen the situation.
Could we have specific parts used (aftermarket clutch, etc.) that worked to correct the problem, please?
Thanks. :yesnod:
Could we have specific parts used (aftermarket clutch, etc.) that worked to correct the problem, please?
Thanks. :yesnod:
Thread Starter
Le Mans Master
Joined: Aug 2002
Posts: 8,472
Likes: 38
From: Houston TX
St. Jude Donor '11
Re: Drill Mod Question (Umrswimr)
I too am a little concerned about how intrusive the process is. With all the drilling, cutting and tapping there's a good chance to introduce lots of metal bits into the system but I absolutely cannot deal with the spongy pedal to the floor thing!
Robert, I can't see why removing the restrictions would increase pedal pressure or how adjusting the CMC would affect pedal pressure. :confused:
Robert, I can't see why removing the restrictions would increase pedal pressure or how adjusting the CMC would affect pedal pressure. :confused:
