Increase master cylinder bore with Mendeola?

[Perkster029]

So, I have not installed a seat yet. And maybe I have short, stubby little legs. But, I'm trying to set a pedal stop, and (in gear) the clutch pedal seems to need to go almost all the way to the firewall in order to get the wheels free (be able to spin). It's like 6-7 inches of travel, and I'm not looking forward to doing that while driving.

My question to you people is: has anyone replaced the FFR-provided master cylinder with a larger bore? I think I would accept a harder pedal for less required pedal travel.

Couple of details:
My Mendeola has a tilton release bearing (hydraulic throw out)
The threaded bolt from the cylinder is such that the end of the bolt is flush with the inside of the clevis with maaaybe one thread extra sticking out on the inside. None of the binding that Shane cautioned about seems to be affecting me

Update: I switched out to the 7/8", and that did the trick. Clutch stop is now set several inches from the firewall, and it's not toooo heavy. But I won't be driving after leg day.

[VRaptor SpeedWorks, LLC]

Sounds to me like you probably have an issue with the slave or the system is not bled completely? I admit I have no experience with the Tilton slave...the Mendys that we've had in here had the standard Mendy-supplied slave on the pass side of the trans, and all of them so far have required adjustment to get the proper gap between the T.O. brg and clutch.....and had the issue you're talking about. That was caused by too much gap between the T.O. and clutch fingers......1/2 of the pedal travel was doing nothing but taking up the gap, and only the last half of travel actually was working to disengage the clutch. I would guess you have the same situation if you have the system bled well. The unfortunate part of that, with an internal slave like you have......is that the solution would require pulling the trans out in order to put the proper amount of shims behind the slave to eliminate most of the gap.

This is pretty easy to see on the Mendy.....just lay under the bellhousing and look up at the clutch while you have a helper push the clutch pedal. The slave should not be touching the PP fingers, but should be very close. If you have a big gap there....like an 1/8"....you're probably going to have to install some shims.

[SteveE]

I had the same issues as I believe that I might have the first Mendy with the Tilton supplied hydraulic release bearing. If you read the Tilton instructions it is paired to work best with a 7/8" bore master cylinder. I did change mine out as this was required to get everything to function properly. I do believe that a shim is actually needed to attain the correct .100" - .150" bearing clearance.

With that said mine is up and working without it but as you state it goes all the way to the floor, and I have gotten used to it. Did manage to get around 700 miles put on it this summer and will be doing a inspection of it this winter to see how things are looking. Hopefully this helps you.

Steve

[crash]

I was going to say that he hydraulic throughout is pretty much brand new for the Mendeola, so this will likely be a "try it and see" type of thing.

[Shoeless]

I had the same issues as I believe that I might have the first Mendy with the Tilton supplied hydraulic release bearing. If you read the Tilton instructions it is paired to work best with a 7/8" bore master cylinder. I did change mine out as this was required to get everything to function properly. I do believe that a shim is actually needed to attain the correct .100" - .150" bearing clearance.

With that said mine is up and working without it but as you state it goes all the way to the floor, and I have gotten used to it. Did manage to get around 700 miles put on it this summer and will be doing a inspection of it this winter to see how things are looking. Hopefully this helps you.

Steve

Hey SteveE,

Did you ever try your setup with the 3/4 master cylinder? I remember talking with Mike Mendeola a while ago and he claims to stay with the 3/4. Maybe that's the same BS I get from him on my delivery.

[SteveE]

Hey SteveE,

Did you ever try your setup with the 3/4 master cylinder? I remember talking with Mike Mendeola a while ago and he claims to stay with the 3/4. Maybe that's the same BS I get from him on my delivery.

Yes, I did try the 3/4 that comes with the kit, my issue was I could not get enough travel out of it to engage the clutch. After talking with Tilton and reviewing their instructions and spec sheet i went with the 7/8 Master Cylinder. This has worked fine for me so far, yes I still have full pedal travel and like i said I plan to give this a good inspection this winter to ensure everything is still in good order.

Shoeless, yes I went through the same on my delivery, did you ever receive yours?

Steve

[VRaptor SpeedWorks, LLC]

0.150 gap seems pretty huge to me? Is that really what they recommend? I would think that 1/3rd of that would still be excessive.....

[Shoeless]

Yes, I did try the 3/4 that comes with the kit, my issue was I could not get enough travel out of it to engage the clutch. After talking with Tilton and reviewing their instructions and spec sheet i went with the 7/8 Master Cylinder. This has worked fine for me so far, yes I still have full pedal travel and like i said I plan to give this a good inspection this winter to ensure everything is still in good order.

Shoeless, yes I went through the same on my delivery, did you ever receive yours?

Steve

Well crap, I guess I'll go get the 7/8" master cylinder now and do the modification and powder coating of it, but i guess its better to do it now before my install.

I have still yet to get mine. After no response from Mike for a bit, I finally got Ian on the phone today. I guess Mike had some medical issues earlier in the month and got a couple ambulance rides to the hospital. Now he is back in the hospital again. No wonder I couldn't get him to respond. I'm trying to be patient, and I hope Mike gets well soon, but this is beyond ridiculous.

[SteveE]

Shoeless

I verifed, yes i have the 7/8. Sent you pm with number if you want to discuss.

Steve

[Mendeola]

So, I have not installed a seat yet. And maybe I have short, stubby little legs. But, I'm trying to set a pedal stop, and (in gear) the clutch pedal seems to need to go almost all the way to the firewall in order to get the wheels free (be able to spin). It's like 6-7 inches of travel, and I'm not looking forward to doing that while driving.

My question to you people is: has anyone replaced the FFR-provided master cylinder with a larger bore? I think I would accept a harder pedal for less required pedal travel.

Couple of details:
My Mendeola has a tilton release bearing (hydraulic throw out)
The threaded bolt from the cylinder is such that the end of the bolt is flush with the inside of the clevis with maaaybe one thread extra sticking out on the inside. None of the binding that Shane cautioned about seems to be affecting me

Revised:
Sorry I made the mistake of grabbing the wrong file.
That is if you are running the small clutch.
You all will be running the 10.5"-11" clutch with this set up this WILL MOVE YOU TO USING THE 7/8" BORE MASTER.
If the 7/8" is to heavy the the guys with the external slave SDR transaxle were using a 13/16" bore to make it a bit softer.

https://www.wilwood.com/MasterCylind...erCylinderList

https://tiltonracing.com/wp-content/...tion-Sheet.pdf

[SteveE]

https://tiltonracing.com/wp-content/...tion-Sheet.pdf

okay if that is what is now being sent with the Mendeola then they have changed it as that is not the one that came with mine. I would disregard what I have said above.

Shoeless,

I would wait and see what you end up with before changing your master cylinder.

Steve

[crash]

Just to clarify and summarize...the Tilton instructions say to use a 3/4 MC and that the gap should be between .170 and .230 on a NEW Tilton 7.25" clutch. This hydraulic throughout is not the same as the original hydraulic throughout that was shipped from Mendeola with a few of the first units to use the hydraulic throughout option so those may need a larger MC. It sounds like the 7/8" MC solves the issue on the early models.

[VRaptor SpeedWorks, LLC]

The instructions clear up why the .170"-.230" initial clearance does not create a problem since the T.O. does not retract "back to zero" when released.....it only retracts back as far as the clutch fingers push it back.....so there is essentially zero clearance when you begin to push the clutch pedal.

[Shoeless]

This definitely clears everything up. I'm glad this was discussed as I had the old Tilton documentation for the 60-8100 in my files.

Glad I don't have to modify another master cylinder that was a pain, but they came out nice.

[Mendeola]

Please see revision.

[Perkster029]

Update: I switched out to the 7/8", and that did the trick. Clutch stop is now set several inches from the firewall, and it's not toooo heavy. But I won't be driving after leg day.