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It's the same except for the fittings.
In that case, why is there discrepancy in dimensions from Konnie's measurements vs GTO9090 measurements? Maybe just tolerances?
One other thing that could affect the slave cylinder travel is flexible rubber line expansion. I doubt it would be that much.
 

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Clarifications in regards to slave cylinder cross-sectional area

In post #3, Konnie says he has confirmed the area is 1.205 but does not show the math

In post #7, he shows a picture that the width between inner D and outer D is 0.210"

So if you take the established measured inner D of 1.43 and add 0.210 x 2 you get an outer D of 1.85 from Konnies pics. This results in an area of 1.082 (my math being in post #116)

So I am not sure where the 1.205 came from. Perhaps a typo or used the wrong numbers in his equation?

At any rate, my measured Outer D was 1.87 which is not all that crazy different from 1.85 that Konnie measured so I would say the actual area is closer to my last post #117 where I calculate 1.130
 

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Clarifications in regards to slave cylinder cross-sectional area

In post #3, Konnie says he has confirmed the area is 1.205 but does not show the math

In post #7, he shows a picture that the width between inner D and outer D is 0.210"

So if you take the established measured inner D of 1.43 and add 0.210 x 2 you get an outer D of 1.85 from Konnies pics. This results in an area of 1.082 (my math being in post #116)

So I am not sure where the 1.205 came from. Perhaps a typo or used the wrong numbers in his equation?

At any rate, my measured Outer D was 1.87 which is not all that crazy different from 1.85 that Konnie measured so I would say the actual area is closer to my last post #117 where I calculate 1.130
You sound serious here :). Designing something new, or just like messing with numbers?
 

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I've just been doing a ton of research on the subject and wish to share my interesting finds. Excuse me while I nerd out and please correct me if you think my math or logic is incorrect. Here's another one to chew on for people that like the analysis.

It is pretty unanimously agreed that the Tick Master Cylinder has helped many people with clutch separation and faster shifts. And we all know why because it is a larger bore which means stiffer pedal feel because you have less hydraulic advantage BUT you get a quicker release because you are moving fluid faster and you get more release because it can move a large total volume of fluid. Ok, so this info is established but let's look at the numbers.

Stock MC
Stroke = 1.25" as measured by Konnie (do you guys think you get full stroke or does it hit the pedal hit the floor? How much stroke do you lose from this?)
Diameter = 3/4" as measured by Konnie
Resuting area = 0.442 in^2
Volume moved = 0.553 in^3 assuming FULL stroke
Resulting slave movement = 0.489"


Tick MC version 1 (no longer sold)
Stroke = 1.1"
Diameter = 13/16"
Resuting area = 0.518 in^2
Volume moved = 0.570 in^3 assuming FULL stroke
Resulting slave movement = 0.504"


Tick MC version 2 (currently sold)
Stroke = 1.1"
Diameter = 7/8"
Resuting area = 0.601 in^2
Volume moved = 0.661 in^3 assuming FULL stroke
Resulting slave movement = 0.585" (19.6% more than stock MC)

Ok now to calculate pedal effort, you compare the area of the Tick MC vs. Stock MC only since pedal geometry and slave geometry are common. (0.601-0.442)/0.442 = 35.9% more pedal effort. Anyone with a Tick MC (including me) can vouch for this because it really does feel much much harder to push.

So this is interesting to me, you get 19.6% more separation than stock MC but you have 35.9% more pedal effort.

Even more interesting, the math would prove that you need to stroke the Tick MC 0.92" if you want to get the same Volume movement as the Stock MC which is just short of the full stroke of 1.1". BUT with that being said you hear a lot of people have their Tick MC adjusted way below the brake pedal position. They should not really be getting that great of separation with such a short stroke.

This leaves me with the conclusion that the Tick MC using a Tilton cylinder is just "better" in design than the Stock MC. When you analyze all of the data and account for all of the reviews online and on the forums, you would likely conclude that the Tick really is better. But why? The numbers show it is not that significant. Here are my speculations:

1. Less flex all around. I think the cylinder has more metal components and less plastic than stock and it just has way less "give" when it pushes fluid, maybe even less blow-by. Also, Tick supplies you with a SS braided line to replace the stock rubber hose. This could have a significant impact alone. This could explain why Konnie did not get anywhere close to 0.489" of travel.

2. It is faster acting. I think the Tilton has less restrictions when pushing fluid out but I cannot prove this. Also, because of the larger bore, you really are moving fluid faster to the slave which gives you a quicker clutch release if your foot velocity is the same for both applications. This gives a much better driving experience and allows you to bang through gears faster.

3. Maybe the Stock MC does not actually get 1.25" of travel when installed on the car. We all know that our pedal hits the floor before full stroke and this is a good thing because you do not want to bottom out a hydraulic cylinder with the force of your foot and the leverage from the pedal. You would break it so quickly. But this begs the question, how much piston travel does the stock MC actually get? I am going to reinstall mine this weekend and find out!
 

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3. Maybe the Stock MC does not actually get 1.25" of travel when installed on the car. We all know that our pedal hits the floor before full stroke and this is a good thing because you do not want to bottom out a hydraulic cylinder with the force of your foot and the leverage from the pedal. You would break it so quickly. But this begs the question, how much piston travel does the stock MC actually get? I am going to reinstall mine this weekend and find out!
Here is where adjustable clutch pedal stop becomes pretty good idea. It not only eliminates unnecessary pedal travel, but acts as a safety device to prevent blowing out the slave cylinder and applying too much pressure on PP fingers and crank shaft trust bearings.
Even more important with aftermarket master cylinder that has larger capacity.
 

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2. It is faster acting. I think the Tilton has less restrictions when pushing fluid out but I cannot prove this. Also, because of the larger bore, you really are moving fluid faster to the slave which gives you a quicker clutch release if your foot velocity is the same for both applications. This gives a much better driving experience and allows you to bang through gears faster.
Yes, larger bore is resulting in shorter pedal stroke. It’s good and bad. Sometimes longer pedal stroke is better for clutch modulation. And softer pedal is more user friendly in traffic.
Also, more pressure on the clutch pedal can be problematic with GTO firewall. People say firewall can develop cracks as it’s not strong enough to withstand extra pressure. Maybe has something to do with this car being designed as a right-hand drive car to start with?
 

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Even more interesting, the math would prove that you need to stroke the Tick MC 0.92" if you want to get the same Volume movement as the Stock MC which is just short of the full stroke of 1.1". BUT with that being said you hear a lot of people have their Tick MC adjusted way below the brake pedal position. They should not really be getting that great of separation with such a short stroke.
Pedal stroke also depends on the clutch itself.
Different strokes for different clutches for different people lol.
Personally, I would adjust clutch pedal higher via adjustable master cylinder rod and use pedal stop to limit pedal travel.
It’s personal preference; pedal position.
I think it is also possible to order master cylinder with different diameter to fine tune the system to ones liking.
 

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I think it is also possible to order master cylinder with different diameter to fine tune the system to ones liking.
This is exactly what I am doing now. I bought the Tick MC and it's not the most enjoyable to drive. I then bought a Tilton 75 series 3/4" bore and it bolts onto the Tick adapter piece. This is when I realized that because of the 1.1" stroke I would actually have less fluid movement than stock (that's a no no). So now today my 13/16" bore cylinder arrived and I will install it this weekend. The math works out to something like 17% more pedal effort which is a lot better than 36%.

The other option is to go back to stock since there seems to be nothing wrong with my stock unit but I just think it is an inferior design to the Tilton and therefore I won't do it. My dream would be for Tilton to have a 3/4" bore with 1.25" travel but that just doesn't exist. The 3/4" bore is an ideal pedal feel IMO. 13/16 hopefully is a good common ground.

I believe the root of the issue resides in the stupid design of the concentric slave cylinder. I wish they would have gone the traditional external slave + fork route on this car.
 

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This is exactly what I am doing now. I bought the Tick MC and it's not the most enjoyable to drive. I then bought a Tilton 75 series 3/4" bore and it bolts onto the Tick adapter piece. This is when I realized that because of the 1.1" stroke I would actually have less fluid movement than stock (that's a no no). So now today my 13/16" bore cylinder arrived and I will install it this weekend. The math works out to something like 17% more pedal effort which is a lot better than 36%.

The other option is to go back to stock since there seems to be nothing wrong with my stock unit but I just think it is an inferior design to the Tilton and therefore I won't do it. My dream would be for Tilton to have a 3/4" bore with 1.25" travel but that just doesn't exist. The 3/4" bore is an ideal pedal feel IMO. 13/16 hopefully is a good common ground.

I believe the root of the issue resides in the stupid design of the concentric slave cylinder. I wish they would have gone the traditional external slave + fork route on this car.
The 13/16" bore master is a good compromise. Pedal feel is also helped by stepping up to a dual clutch. When I had a single Monster Level 3, the pedal's stiffness combined with the single 6 puck disc made the car unenjoyable with the 7/8" bore master. Moving to the LT1-S, the car became much more enjoyable to drive.

Of course, upgrading to a dual clutch is much costlier than changing out masters. I have contemplated going to a 13/16" bore just to gauge the difference in feel versus performance, but I haven't pulled the trigger on that just yet.
 

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This is exactly what I am doing now. I bought the Tick MC and it's not the most enjoyable to drive. I then bought a Tilton 75 series 3/4" bore and it bolts onto the Tick adapter piece. This is when I realized that because of the 1.1" stroke I would actually have less fluid movement than stock (that's a no no). So now today my 13/16" bore cylinder arrived and I will install it this weekend. The math works out to something like 17% more pedal effort which is a lot better than 36%.

The other option is to go back to stock since there seems to be nothing wrong with my stock unit but I just think it is an inferior design to the Tilton and therefore I won't do it. My dream would be for Tilton to have a 3/4" bore with 1.25" travel but that just doesn't exist. The 3/4" bore is an ideal pedal feel IMO. 13/16 hopefully is a good common ground.

I believe the root of the issue resides in the stupid design of the concentric slave cylinder. I wish they would have gone the traditional external slave + fork route on this car.
Those work so well and clutch fluid doesnt get dirty. Id imagine packaging constraints would have been an issue with headers coming down both sides.
 

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This is exactly what I am doing now. I bought the Tick MC and it's not the most enjoyable to drive. I then bought a Tilton 75 series 3/4" bore and it bolts onto the Tick adapter piece. This is when I realized that because of the 1.1" stroke I would actually have less fluid movement than stock (that's a no no). So now today my 13/16" bore cylinder arrived and I will install it this weekend. The math works out to something like 17% more pedal effort which is a lot better than 36%.
3/4” bore and 1.1” stroke may be enough. Lift the rear ended and see if you can freely turn the wheel with car in gear and clutch pedal depressed.
 

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Ok so more research

Tonight I put the Stock MC back in and measure how much stroke you get at the cylinder until the pedal hits the floorboard. It was somewhere between 1 1/16" and 1 3/32" so you don't actually get the full 1.25" stroke. This was actual measured rod travel with my ass under the dash.

Also, I believe most masters have about 0.1" of dead zone before they compress fluid to allow for the reservoir hole to be under no pressure and allow reservoir fluid to gravity flow downwards when the pedal is not depressed. I confirmed this with the Tilton MC I have. Even though it is advertised at 1.1" stroke. When you stroke it empty it is truly 1.1", but when you stroke it full of hydraulic fluid there is about 0.1" of travel you can get by hand with no pedal leverage. In this 0.1" of travel you can also see the fluid reservoir surge which further proves there is 0.1" of no compression. I think a cross section view of any MC would also show you this.

This changes the stock MC calcs to the following

Stock MC
Stroke = 1 3/32" measured as actual stroke by me
Diameter = 3/4" as measured by Konnie
Resuting area = 0.442 in^2
Volume moved = 0.483 in^3 assuming FULL stroke
Resulting slave movement = 0.427"

But if it is true that most MCs have approx 0.1" of deadzone then the calcs would be the following

Stock MC
Stroke = 0.994" measured as actual stroke by me minus 0.1" of deadzone
Diameter = 3/4" as measured by Konnie
Resuting area = 0.442 in^2
Volume moved = 0.439 in^3 assuming FULL stroke
Resulting slave movement = 0.388"

My plan is to still install the 13/16 Tilton this weekend.
 

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The 13/16" bore master is a good compromise. Pedal feel is also helped by stepping up to a dual clutch. When I had a single Monster Level 3, the pedal's stiffness combined with the single 6 puck disc made the car unenjoyable with the 7/8" bore master. Moving to the LT1-S, the car became much more enjoyable to drive.

Of course, upgrading to a dual clutch is much costlier than changing out masters. I have contemplated going to a 13/16" bore just to gauge the difference in feel versus performance, but I haven't pulled the trigger on that just yet.

Yo I'll report back my findings. I have a pretty darn good muscle memory and will be able to report feedback how the 13/16 feels compared to both the 7/8 Tilton and 3/4 Stock.

In retrospect, dual clutch may have been a good idea but I literally installed a Monster stage 2 less than 1000 miles ago.
 

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OEM master is just fine IMO. If it works, it works.
Does anyone actually have any specific issues with OEM master?
I'm unfamiliar with your setup, are you running a stock clutch? From my research it is mostly the ppl with aftermarket clutches and much stiffer PP fingers that start to complain about separation issues.

I'm trying to be ultra-cautious because when bought the car Jan 2019 you had to fight it to get into first,reverse and shifting into 3rd at WOT was not possible. It shifted like poo poo and I am surprised I even bought it. Because I had never dropped a transmission I was hoping for the miracle fix from the Tick MC so I bought that. Did not really have any effect at all. I took everything apart and found the flywheel had the most severe hot spotting I have ever seen (from google images). Kinda tells me the cluch was dragging with the previous owner. I found that the slave spacing was out of spec too. So I bought a brand new Monster stage 2 and measured the slave spacing about 35 times with a caliper to make sure I was between 0.0625 and 0.200 as mentioned in this thread. Now that it is all back together, I decided I hate the drivability of the 7/8 master and so now I am experimenting. This stuff also genuinely interests me so I am enjoying myself while doing so.

On a side note, you can tell the blocker ring for my 3rd gear is on the way out because of the PO and the dragging clutch because you still have to "push" a little harder to get into 3rd at WOT but it does go in without any bad noises. From my research, this is the first symptom ppl notice when they have a dragging clutch. On our cars it's always 3rd gear WOT.
 

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Wow that looks like clutch material melted to the flywheel. Mine did not look like that.

My flywheel was clean and flat but just huge spots of blue do to extreme temps throughout the whole contact surface. The backside of the flyhweel looked like the front because the heat penetrated through. I imagine the PO had that thing glowing red quite often.
 

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I got the 13/16 installed and bled Sunday. I have not taken it out for a drive yet or even fired up the car to adjust the pedal stroke.

But I wanted to mention for those bleeding that I made up my own method and decided to jack up the rear of the car as high as possible. I have an angle gauge that measured I got a full 8 degrees of tilt. I did this because the MC has its reservoir connection towards the rear of the car and the slave cylinder has its bleed screw at the rear of the car as well. I figured this would increase the chances of getting air out of the system.

I also followed a bleed procedure given to me by a Tilton engineer where you apply light pressure to the pedal, then crack the bleeder and slowly press, then close the bleeder before it hits the floor. This is opposed to the most commonly used method that you first push the pedal all the way down, then crack the bleeder and allow the retracting PP fingers to force fluid out at high speed. He said when you do that you agitate the air and aerate it into very small bubbles as it expands rapidly. Kind of made sense to me.
 
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