Swapping Tilton MC for Wilwood MC

[chjort]

Well, it appears that I am the latest victim of Wilwood master cylinders failing. 3500 miles on the car, and the brakes went soft. I tried re-bleeding, but no dice, looking at the balance bar with the brake pedal depressed, I can see that the rear circuit MC is all the way in. So, it looks like it needs replacing. I don't really want to put in another Wilwood MC in if its just going to fail, so I was thinking of switching to a Tilton. Has anyone done this? Looks to me like this Tilton MC would work as a replacement https://www.speedwaymotors.com/Tilton-75-Series-Master-Cylinder-Only,413928.html

If you switched is that part you used, or was it something else? Is there any other brand that you would recommend I look at? Thanks!

[Mike.Bray]

Go with Tilton.

A series 75 or series 76 will drop right in.

[Fman]

The Tilton 75 series has 6 different bore options from 5/8 - 1" bore. I would call Tilton to make sure you get the exact same bore as the other Wildwood MC. FWIW I lost my Wildwood clutch MC at 2000 miles. I am at 6300 miles now and new replacement has been holding. If I loose another Wildwood will also give Tilton a try.

[Alec]

Well, it appears that I am the latest victim of Wilwood master cylinders failing. 3500 miles on the car, and the brakes went soft. I tried re-bleeding, but no dice, looking at the balance bar with the brake pedal depressed, I can see that the rear circuit MC is all the way in. So, it looks like it needs replacing. I don't really want to put in another Wilwood MC in if its just going to fail, so I was thinking of switching to a Tilton. Has anyone done this? Looks to me like this Tilton MC would work as a replacement https://www.speedwaymotors.com/Tilton-75-Series-Master-Cylinder-Only,413928.html

If you switched is that part you used, or was it something else? Is there any other brand that you would recommend I look at? Thanks!

There have been quite a few of these posts lately, reporting Wilwood MC failures with very low mileage. I am awaiting mine being returned from Wilwood. I received an email invoice 2 days ago with no explanation, suggesting that they rebuilt it and sent it back to me. No acknowledgment of defect, no offer to reimburse the $100 I spent at Summit buying a replacement so that I could repair my car quickly, no apology for me losing my brakes while driving, which could, of course, have been deadly.

I hope FFR is monitoring this situation.

[Mike.Bray]

If you switched is that part you used, or was it something else? Is there any other brand that you would recommend I look at? Thanks!

If you change to Tilton do the calculations and make sure you've got the correct bore size. I ended up with three different bore cylinders, the Wilwoods from FFR are all 3/4".

[danmas]

I have a couple wilwoods that I won’t be using (thanks to Mike’s advice). If anyone needs one while they wait for a rebuild or replacement from wilwood, pm me and I will ship it to you. Ask that you cover shipping and pay it forward somehow.

Dan

[RogerRoger88]

For those of us that are about to start our builds, would you all recommend that we not even use the Wilwood MC and use the Tilton from the start ?

[F500guy]

Couple items to note, it is easier the earlier in the process you do this. Listed below are the differences between the 2. You would need the kit because you will need the top for the reservoir inlet. I plan to do this this weekend, so will have more info and pictures next week.

Tilton has 3-AN outlet, so that will need fittings to get it to a regular brake line flare fitting. (I plan to use a banjo fitting to get to the 4-AN for the clutch, for the brakes I have 2 options, banjo (Requires a 3-AN coupler) or 3-AN to NPT then the supplied NPT 90 deg to the flare. will figure that out when I see what fits better at install time.

The inlet hose for the reservoir on the Tilton is 5/16 instead of 1/4. (I plan to install a SS splice to up size my hose in the footbox)

I stuck with 3/4 bore all the way around, I will not run the car hard enough to require completing the math for the front/rear bias based on different bores-My numbers show 3/4 front and rear to be a very safe and conservative setup, maybe not optimal for serious track stuff. My through-out bearing (Mcleod) called out 3/4 master cylinder and that works. (personal preference on pressure and throw would dictate a change on that).

[Mike.Bray]

For those of us that are about to start our builds, would you all recommend that we not even use the Wilwood MC and use the Tilton from the start ?

I didn't even take mine out of the box, that's my confidence level.

I would say find someone with a completed MKIV and have a look at what it takes to change a MC on a finished car.

[OB6]

Here's what my conversion looks like. There's probably a cleaner way to make the hose transition, but this works. Just keep the clamp acrews heads facing the access hole for future maintenance.

For the brake MC's I used a straight -3AN male/male adapter to a -3AN swivel female/male 90. On the clutch hose I used a straight -3AN male/male adapter directly to the flex clutch hose. I used AN fittings throughout my build, so your setup and needs may be different.

Nevermind the wiring mess... it's not done. :)

202398

[JimStone]

Would like to see some hard data on this whole Wildwood MC problem.

Is this just a frequency illusion?



Not a perfect illustration, but consider this:

FFR ships around 1,000 kits a year, most with the Wildwood MCs. If there is a hypothetical 5% failure rate (no idea what it actually is) that's 50 people coming in here loudly decrying the Wilwoods.

How many people actually have Tilton's? 50 per year? Say the same 5% failure rate. That's only 2.5 people/yr to come on here and complain.

[OB6]

I see the desire for hard data, and normally I'd like to see it too. But the anecdotal evidence and in my case, first-hand experience, was plenty. We're not talking about light bulbs.

[BrewCityCobra]

Here's what my conversion looks like. There's probably a cleaner way to make the hose transition, but this works. Just keep the clamp acrews heads facing the access hole for future maintenance.

For the brake MC's I used a straight -3AN male/male adapter to a -3AN swivel female/male 90. On the clutch hose I used a straight -3AN male/male adapter directly to the flex clutch hose. I used AN fittings throughout my build, so your setup and needs may be different.

Nevermind the wiring mess... it's not done. :)

202398

OB6,

Are those the Series 75 master cylinders? I had a pair of Series 74 in my hand and those babies were huge! These seem much more manageable.

[OB6]

OB6,

Are those the Series 75 master cylinders? I had a pair of Series 74 in my hand and those babies were huge! These seem much more manageable.

They're 75's. Identical in size to the WW's. I haven't seen the 74's... maybe they are indeed bigger.

[cv2065]

Would like to see some hard data on this whole Wildwood MC problem.

Is this just a frequency illusion?



Not a perfect illustration, but consider this:

FFR ships around 1,000 kits a year, most with the Wildwood MCs. If there is a hypothetical 5% failure rate (no idea what it actually is) that's 50 people coming in here loudly decrying the Wilwoods.

How many people actually have Tilton's? 50 per year? Say the same 5% failure rate. That's only 2.5 people/yr to come on here and complain.

Although I understand the aggravation and seriousness of a failure, I would have to agree. If you look at Summit, Amazon and JEGS reviews for these Wilwood MCs, although a small sampling, they are all 4 and 5 star ratings. In sheer volume, based on those reviews, I would have to believe that Wilwood sells many more of their MCs than Tilton. For every 1 review of Tilton, you've got ten fold of the Wilwood. And the old adage that many only review when they have a negative to tell. Do an internet search on failure and there is very little. Again, I'm not discounting those that experience a failure, and hopefully I'm not a casualty either, but to strip out what you have and spend the extra time, money and effort to swap over is of course one's choice, but a little extreme...IMO.

[edwardb]

Would like to see some hard data on this whole Wildwood MC problem.

Is this just a frequency illusion?

Not a perfect illustration, but consider this:

FFR ships around 1,000 kits a year, most with the Wildwood MCs. If there is a hypothetical 5% failure rate (no idea what it actually is) that's 50 people coming in here loudly decrying the Wilwoods.

How many people actually have Tilton's? 50 per year? Say the same 5% failure rate. That's only 2.5 people/yr to come on here and complain.


Although I understand the aggravation and seriousness of a failure, I would have to agree. If you look at Summit, Amazon and JEGS reviews for these Wilwood MCs, although a small sampling, they are all 4 and 5 star ratings. In sheer volume, based on those reviews, I would have to believe that Wilwood sells many more of their MCs than Tilton. For every 1 review of Tilton, you've got ten fold of the Wilwood. And the old adage that many only review when they have a negative to tell. Do an internet search on failure and there is very little. Again, I'm not discounting those that experience a failure, and hopefully I'm not a casualty either, but to strip out what you have and spend the extra time, money and effort to swap over is of course one's choice, but a little extreme...IMO.

Agree completely Said something similar a few days ago in another thread. Not going to repeat it (or argue). Check the link if you want: https://thefactoryfiveforum.com/showthread.php?49501-Clutch-Pedal-Fitment-Throw-Question&p=560385&viewfull=1#post560385. I don't question that several have found issues with the Wilwood MC's. A couple forum members mention this every time the question comes up. But a whole bunch have been installed without issues. Also agree they're not fun to change or service on a completed build. I've only used a couple Tilton parts in my builds (not MC's) and agree they seem to be good quality. But I'd say the same for the multiple Wilwood brake setups I've installed. If it's worth it to you to spend a few hundred bucks and use the Tilton parts, your choice. As we say around here, it's your build. But the data is anecdotal. I had an infant mortality issue with one Wilwood MC that turned out to be a defective O-ring. Didin't fail but leaked fluid into the boot. Other than that, I'm five builds and thousands of miles with no issues. My Coupe is about to turn 8K with three Wilwood MC's. I'll bet lots of forum members could cite similar experience.

Side note, as some know I'm currently in the process of building an airplane. A different but also enjoyable experience. The brand and model I'm building also has a pretty active social media presence. I see the same exact thing. A couple reports of a problem and new and existing builders jump in with doubts, asking if they should replace, etc. Even though there's an established user base not reporting widespread issues. In this case, it's slightly different because the manufacturer issues service bulletins, safety alerts, etc. when there's a known problem. Slightly different than the certified world, but the same idea. Typically no correlation between the latest social media excitement and what the mfg has found and provided a fix for. I'm starting to dabble a bit with 3D printing. Guess what? Same thing...

[OB6]

I don't think there's a right or wrong answer here. You need to do what makes sense to you, even if might seem extreme, unnecessary, over the top, silly, or a waste of time to others. Use the information you have and make a decision. Replacing all three seemed prudent to me, but this is coming from a guy going the LS3 route (which many consider questionable judgment).

[Dave Tabor]

Side note, as some know I'm currently in the process of building an airplane. A different but also enjoyable experience. The brand and model I'm building also has a pretty active social media presence. I see the same exact thing. A couple reports of a problem and new and existing builders jump in with doubts, asking if they should replace, etc.

Could any of these items get you killed liked a failed master cylinder? In a plane I suppose any part failure could get dead.

A guy local to me just had a rear brake caliper crossover O-ring fail and lost his brakes on the track (Gen III Coupe). Any failure anywhere whether it be a master cylinder or a brake caliper and due to the balance bar setup you lose brakes - is this correct?

Is there any way to mitigate this - e.g. fabricate some sort of balance bar 'limiter' so in the event of a master cylinder/caliper by-pass the balance bar has something to leverage on in order to pressure the other circuit? In the meantime I'm glad that I have a manual, lever-actuated 'emergency' brake.

Dave
Gen III #17
22,000+ miles

[Mike.Bray]

I'll add a few additional thoughts since I'm a strong advocate of the Tilton master cylinders.

I've been driving for almost 50 years and have owned nearly 50 cars or trucks. Conservatively estimating I've driven about 1.2M miles. I've not had one, not one single MC failure. I don't know what the acceptable failure rate of OEM master cylinders is but it must be one in a million or something close to that level.

The quantities of Wilwood master cylinders put out by Factory Five are substantially lower but just here on this forum how many failures have been reported? And some right out of the box. That's enough data for me right there.

It's known that with the Wilwood pedal box failure of one MC results in complete brake failure. There is no backup like with an OEM dual master cylinder. That doesn't sound like a good thing to me.

Both the Wilwood and Tilton master cylinders are aluminum but with a different piston design. The Wilwood piston is aluminum and the Tilton is steel. However, and this is big, the bore of the Tilton is hard anodized. For you non-metallurgists hard anodizing converts the surface of aluminum into aluminum oxide. Aluminum oxide is equivalent to sapphire or ruby on the gem scale and is what grinding wheels are made from. In other words it is extremely hard, close to diamond hard. Translated, this means the bore in a Tilton MC will never wear. Ever.

If anyone is interested here is a good video comparing the Wilwood and Tilton master cylinders.


https://www.youtube.com/watch?v=Hz4AlAt7DJ8&t=147s

[JMD]

I'll add a few additional thoughts since I'm a strong advocate of the Tilton master cylinders.

I've been driving for almost 50 years and have owned nearly 50 cars or trucks. Conservatively estimating I've driven about 1.2M miles. I've not had one, not one single MC failure. I don't know what the acceptable failure rate of OEM master cylinders is but it must be one in a million or something close to that level.

The quantities of Wilwood master cylinders put out by Factory Five are substantially lower but just here on this forum how many failures have been reported? And some right out of the box. That's enough data for me right there.

It's known that with the Wilwood pedal box failure of one MC results in complete brake failure. There is no backup like with an OEM dual master cylinder. That doesn't sound like a good thing to me.

Both the Wilwood and Tilton master cylinders are aluminum but with a different piston design. The Wilwood piston is aluminum and the Tilton is steel. However, and this is big, the bore of the Tilton is hard anodized. For you non-metallurgists hard anodizing converts the surface of aluminum into aluminum oxide. Aluminum oxide is equivalent to sapphire or ruby on the gem scale and is what grinding wheels are made from. In other words it is extremely hard, close to diamond hard. Translated, this means the bore in a Tilton MC will never wear. Ever.

If anyone is interested here is a good video comparing the Wilwood and Tilton master cylinders.


https://www.youtube.com/watch?v=Hz4AlAt7DJ8&t=147s

I do see your point as to how the Tilton would probably wear slower than the Wilwood with this configuration, but I would imagine if you A) don't put a lateral load on the rod, and B) keep things clean, it will probably last about as long as you need it to. The fact that he was pushing sideways on that rod caused a load and metal to metal contact that it was never designed for. I don't think there is much metal to metal contact under normal operating conditions and geometries, so shouldn't really be an issue for most operators. The only wear item when properly used should be the seal to bore, correct? That being said, a hard anodized bore does seem clearly superior in reducing friction and wear.

[Railroad]

Failure on the clutch is one thing. Failure on your brakes is a whole nuther issue!

[Mike.Bray]

I do see your point as to how the Tilton would probably wear slower than the Wilwood with this configuration, but I would imagine if you A) don't put a lateral load on the rod, and B) keep things clean, it will probably last about as long as you need it to. The fact that he was pushing sideways on that rod caused a load and metal to metal contact that it was never designed for. I don't think there is much metal to metal contact under normal operating conditions and geometries, so shouldn't really be an issue for most operators. The only wear item when properly used should be the seal to bore, correct? That being said, a hard anodized bore does seem clearly superior in reducing friction and wear.

I should have been more clear in my thoughts. The failures the Factory Five community are seeing with Wilwood master cylinders are happening too soon to be a wear issue, some are bad right out of the box. I just thought the video was interesting in comparing the Wilwood to the Tilton.

The Wilwood failures are a quality control issue which is extremely concerning. It could be the quality, or lack of quality of the castings or the machining of the bore is bad, either the sizing or the surface finish. Terry reported his brand new Wilwood that failed felt "rough" when he actuated it while the new Tilton felt smooth as silk. Obviously if the bore isn't spot on with size and finish it will have an effect on the function and life of the unit.

[cv2065]

I should have been more clear in my thoughts. The failures the Factory Five community are seeing with Wilwood master cylinders are happening too soon to be a wear issue, some are bad right out of the box. I just thought the video was interesting in comparing the Wilwood to the Tilton.

The Wilwood failures are a quality control issue which is extremely concerning. It could be the quality, or lack of quality of the castings or the machining of the bore is bad, either the sizing or the surface finish. Terry reported his brand new Wilwood that failed felt "rough" when he actuated it while the new Tilton felt smooth as silk. Obviously if the bore isn't spot on with size and finish it will have an effect on the function and life of the unit.

You are painting with a very broad brush with not much data behind it, insinuating that every new owner needs to swap out these parts or risk an accident. And of course that FFR is taking a blind eye to faulty parts and putting everyone who buys a kit at risk of complete brake failure. I’m sure that’s not the intention, but that’s the messaging.

Of course, everyone can do what they see fit for their car, but I ran Wilwood MCs in my last car with no issues. And there are thousands of others who have done the same. Maybe get some real QC data and Wilwood input behind the charge before running with it. Is the Tilton unit without issue? Unlikely. Is the Tilton unit better’? Possibly, but no one can really make that call based on one YouTube video and a handful of experiences.

[Mike.Bray]

You are painting with a very broad brush with not much data behind it, insinuating that every new owner needs to swap out these parts or risk an accident. And of course that FFR is taking a blind eye to faulty parts and putting everyone who buys a kit at risk of complete brake failure. I’m sure that’s not the intention, but that’s the messaging.

I'm not insinuating anything, I'm flat out saying the reported failure rate for a critical safety component as reported on this forum alone is unacceptably high for me. Paul reported he's "only" had one failure out of 15 cylinders. My friend Terry up the road had a failure recently right out of the box.

We're talking about a critical component that should have a reliability rating of at least 4 nines (0.9999) and realistically 5 nines (0.99999). In just what has been reported here the Wilwoods aren't anywhere close to that. I mean seriously, it's a very simple part. There's no reason for it to have any less reliability that 4-5 nines.

I'm a bit conservative by nature being an engineer and I made my decision on a course of action that made me sleep well at night. What other builders do is purely their decision, I'm just putting it out there.

[Malibu46pt]

I am not sure I have bad mc, but I can’t seem to balance my brake pressure front to rear. I am considering changing the mc’s but I am not sure how to do it with the limited access to the foot box. How have others completed the change after foot box assembly complete and body on. The small access panel really limits removal and install.

[Jeff Kleiner]

You are painting with a very broad brush with not much data behind it, insinuating that every new owner needs to swap out these parts...


Maybe so. But in the past other broad brushes have painted pictures about ball joints or tie rod ends or other components that should be replaced without much data either. In the end, as you say "everyone can do what they see fit for their car."

Jeff

[cv2065]

Maybe so. But in the past other broad brushes have painted pictures about ball joints or tie rod ends or other components that should be replaced without much data either. In the end, as you say "everyone can do what they see fit for their car."

Jeff

Then perhaps FFR needs to do a recall if they are including substandard parts with their kits. Or at least investigate. We are talking about the braking system after all.

[JohnK]

Mike, one of my favorite sayings is, "the plural of anecdote is not data." One of the reasons that there are reported Wilwood failures here is because Wilwood parts ship with these kits. It's entirely possible that if Tilton parts shipped with these kits we'd be talking about Tilton failures. You can google "Tilton MC failure" and find plenty of examples of defective parts. There are just too many variables, including how the parts are installed and maintained, the cleanliness of the entire system, and on and on, to be able to draw meaningful conclusions about statistical reliability based on what's been posted here. I'm not trying to be argumentative or defend Wilwood (I have no skin in the game one way or another). I have no data to support either position. If you want to make a choice based on anecdotes or gut feel or comfort level, by all means do so.

[OB6]

Maybe so. But in the past other broad brushes have painted pictures about ball joints or tie rod ends or other components that should be replaced without much data either. In the end, as you say "everyone can do what they see fit for their car."

Jeff

Perfectly said Jeff. And I'm sure the list is even longer.

Sharing observations and personal courses of action is constructive, in my opinion. My experience with a 33% failure rate points to nothing other than a QC problem -- at least in my mind. Others will and do disagree, but that's what makes this world work.

[lance corsi]

The wilwood piston lacks stability, that is why it tends to wear excessively. The Tilton mc piston more closely resembles an oe mc piston in that it has been lengthened and has the forward portion to stabilize lateral movement if a slight misalignment occurs, which is almost always the case. The steel piston inside a hard anodized bore is a plus also. The Tilton design is superior to the Wilwood design in my opinion.

[Jeff Kleiner]

Then perhaps FFR needs to do a recall if they are including substandard parts with their kits. Or at least investigate. We are talking about the braking system after all.

Or maybe they aren't supplying substandard parts and builders who subscribe to the "If it costs more it must be better" school of thought are replacing supplied parts even if they not experienced failures. After building these cars for 20+ years I can say that when there have been reported issues FFR has been very proactive (think back to the Bilstein shock failures and subsequent recall instituted by Factory Five for example). The Wilwood pedal box and master cylinders came into use in 2008. Wilwood may well be experiencing some Q.C. issues of late but over the course of those 16 years and over 6,000 kits being shipped it's not been an ongoing, chronic problem or a matter of FFR supplying substandard parts.

Now, where did I leave my Kool-Aid?

Jeff

[rich grsc]

Jeff, how many time have I said, "no logic allowed".

[cv2065]

The Wilwood pedal box and master cylinders came into use in 2008. Wilwood may well be experiencing some Q.C. issues of late but over the course of those 16 years and over 6,000 kits being shipped it's not been an ongoing, chronic problem or a matter of FFR supplying substandard parts.

And that was my initial point. If there were some massive QC issues with Wilwood MCs, FFR would have that data through their own customer interactions and I'm sure is on top of their suppliers as well as customer complaints. Especially as it pertains to the braking system. In some cases, large vendors like FFR are actually a part of the QC and R&D efforts for manufacturers like Wilwood.

[OB6]

Jeff, how many time have I said, "no logic allowed".

I completely agree with the logic in Jeff's statement, but my logic told me to replace all three MCs after the clutch MC failed on the bench. I must be awfully conflicted.

[Mike.Bray]

Mike, one of my favorite sayings is, "the plural of anecdote is not data." One of the reasons that there are reported Wilwood failures here is because Wilwood parts ship with these kits. It's entirely possible that if Tilton parts shipped with these kits we'd be talking about Tilton failures. You can google "Tilton MC failure" and find plenty of examples of defective parts. There are just too many variables, including how the parts are installed and maintained, the cleanliness of the entire system, and on and on, to be able to draw meaningful conclusions about statistical reliability based on what's been posted here. I'm not trying to be argumentative or defend Wilwood (I have no skin in the game one way or another). I have no data to support either position. If you want to make a choice based on anecdotes or gut feel or comfort level, by all means do so.

Something I have not mentioned is I made the decision to use Tilton master cylinders even before I ordered my kit. I have had first hand experience with both and as Lance Corsi pointed out the design of the Tilton is superior to the Wilwood. Probably why it costs more. I had the opportunity to look at a finished MKIV before I ordered my kit and it took me about 50ms to figure out I did not want to have to change out a MC in one of these completed cars.

Same with the hydraulic throwout bearing. First one I ever used was a Mcleod and it failed on me in a few hundred miles. This was before the internet so I had to do some old fashioned research talking to people I knew in the street rod and race car industry. Everyone pointed me to the Tilton hydraulic throwout bearing and I never used anything else since. And never had a failure.

I remember when Wilwood came on the scene. I was building street rods and using JFZ brakes, their 4 piston ridged mount caliper was the standard for high end brakes on street rods at the time. Small privately owned company that took real pride in his work. Then Wilwood copied his designs, threw some high production at them, and undersold poor John until he threw in the towel. IMO the Wilwood 4 piston caliper was not as good a piece as the JFZ one and I used both. I have Wilwood brake kits on my MKIV, I wouldn't say they are bad by any means. To me they are good value: quality vs. cost, but they're certainly not Brembos.

I think we can all agree that the odds of having a failure of a Wilwood MC are small. Getting killed by my cat while I'm sleeping is also small but not zero. But IMO there are too many documented failures of this critical component, like I said this simple part should be 4 or 5 nines of reliability. I made a decision in an attempt to insure that I don't have a failure. What anyone else does is purely up to them. Just the same as with ball joints and tie rod ends as Jeff mentioned. If you look at my build details there are quite a number of components that I upgraded from what Factory Five supplied (think Breeze). But that's part of it isn't it?

Happy and safe motoring!

[Dave Tabor]

I'll be changing my master cylinders to Tiltons and I won't be napping with Mike's cat.

It will be interesting to take my Wilwoods apart after 21,000+ miles and have a look.

Still, I wish there was some way to limit the amount of balance bar travel in the event of a particular circuit failure.

Dave
Gen III Coupe #17

[cv2065]

I'll be changing my master cylinders to Tiltons and I won't be napping with Mike's cat.

It will be interesting to take my Wilwoods apart after 21,000+ miles and have a look.

Still, I wish there was some way to limit the amount of balance bar travel in the event of a particular circuit failure.

Dave
Gen III Coupe #17

Out of curiosity, I'd like to see that too Dave. Don't forget the pics! ;)

[phils88gt]

Not that it will effect many but the Tilton 75 and 76 series masters are not abs compatible. If you want that you can't use a 2 bolt master and would need a 79 series master and a Tilton 72-808 pedal assembly.

[SteveWorth]

I have been following thread and debating if it was necessary to proactively change out the Wilwood master cylinders as I am just at the go kart stage.
Well today I was going to go for a short, neighborhood cruise but the clutch only had spring pressure. Closer inspection revealed a drop of fluid on to of the casting at the outlet port.
202924

Looks like the casting is porous at the outlet thread.
Steve

[FF33rod]

My Wilwood MC for the clutch toasted on me a couple of years ago, less than 1000 miles on the car. I was on the road a couple of hours drive and a 1.5 hour ferry ride away from home. A local shop in the town I was in helped me out... They said that this was the 3rd failed Wilwood MC they've seen in the last year. This is totally outside the FFR community. Another "Data point" for those that like data....

Steve

[EK1965]

Another one for the pile. Wilwood clutch master failure almost immediately and struggling with my rear brake circuit as well. I made the mistake of replacing with the equivalent and can attest to the challenge of getting to the clutch MC but now that I have the technique and scars it'll be easy the next time. My plan is to replace all three with Tilton over the winter, as I hate losing confidence in parts.

[Mike.Bray]

Another Wilwood MC bites the dust.

https://thefactoryfiveforum.com/showthread.php?50278-Master-Cylinder-Replacement

[D-Dubya]

Reposting my experience:

My clutch failed last weekend and I have Wilwoods MCs that I installed even though my friend Mike Bray advised me to put Titons in while the car was still under construction. So, yesterday, I had a slow day at work so I went out and decided to make a go of getting the MC's out. Took me about and hour and a half to get all 3 MC's out with the dash completely off. I did not lower the fuse box, but I can see where that might be helpful. Followed basically the same process you described and, while it was a bit tedious and slow, it wasn't as bad as I had expected. Waiting for new Tilton's to arrive (hopefully tomorrow) to start the process of getting this back together.

A good set of "crowfoot" wrenches would have been very helpful. I would also recommend hiring a very small, very strong trained monkey as it is a tight squeeze through that access panel opening.

I only have about 2500 miles on my MKIV so I was a bit surprised at what I found when I broke down the clutch MC. The seal closest to the pushrod was definitely collapsed and the piston had some major abrasions with matching abrasions on the inside of the bore. The fluid that came out was almost black.

[Windsorpower]

Reposting my experience:

My clutch failed last weekend and I have Wilwoods MCs that I installed even though my friend Mike Bray advised me to put Titons in while the car was still under construction. So, yesterday, I had a slow day at work so I went out and decided to make a go of getting the MC's out. Took me about and hour and a half to get all 3 MC's out with the dash completely off. I did not lower the fuse box, but I can see where that might be helpful. Followed basically the same process you described and, while it was a bit tedious and slow, it wasn't as bad as I had expected. Waiting for new Tilton's to arrive (hopefully tomorrow) to start the process of getting this back together.

A good set of "crowfoot" wrenches would have been very helpful. I would also recommend hiring a very small, very strong trained monkey as it is a tight squeeze through that access panel opening.

I only have about 2500 miles on my MKIV so I was a bit surprised at what I found when I broke down the clutch MC. The seal closest to the pushrod was definitely collapsed and the piston had some major abrasions with matching abrasions on the inside of the bore. The fluid that came out was almost black.

Well I’m decided. Anyone figured out which Tilton works best with a newer Forte clutch setup?

[cv2065]

Well I’m decided. Anyone figured out which Tilton works best with a newer Forte clutch setup?

If you are going to replace the Wilwood clutch MC with the Tilton, you’ll want this one. Forte includes a 13/16” MC with his kit.

https://www.summitracing.com/parts/TIL-75-812U

[D-Dubya]

I have just completed replacement of all 3 MC's in my MKIV. Like FF33rod, my clutch MC failed at 2,500 miles, so I decided to take Mike Bray's advice and change all 3 to Tilton's. When I tore down the Wilwood MC that failed, the fluid that came out of it was completely black and the seal closest to the plunger was completely toast. Additionally, there were major abrasions on the plunger end of the piston and corresponding abrasions in the bore (about 1.5" long).

I purchased the Tilton 75-750U kits because they have the cap included. The Tilton's have -3AN outlets and Wilwood's have 1/8 NPT, so you may have to get -3AN to 1/8 NPT adapter (Earls 968703ERL) if you want to use the existing hardware where the brake line terminates to the MC. Unless you want to change the hose size from the reservoirs, you will also need to get 5/16 to 1/4 hose adapters.

Getting the Wilwood's out was not very difficult but getting the Tilton's in was a PITA to say the least. I removed my dash, which turned out to be necessary because you have to go at his from the cockpit and through the access panel. I did this by myself, but for this project two sets of hands is better than one. The most difficult part for me was getting the clutch and middle MC's plungers threaded back into the clevis. Obviously, the clutch is the most difficult because it is the hardest to reach through the access panel. The caps on the Tilton's are much taller and you have to put the hose on before installing, which makes things a little tighter. And don't forget to cut 5/8" off the plungers, just like the Wilwood's. Ask me how I know...

This is not a project you want to tackle when the car is completed but it is doable if you have a lot of patience.

Doug

[OB6]

Nice work Doug. At least you got 2500 miles out if your MC. I got exactly zero miles out of mine. Defective out of the box. I didn't pursue returning it, but rather went down to Summit and picked up three Tiltons. Luckily I didn't have the body on.

[CraigS]

Doug, I now have a 2019 Stingray. I kept reading about the 'Ranger method' of changing the clutch MC fluid. I kept thinking for the first 3 years, heck it's a new car, how could the fluid be bad. Finally decided to change it. I was appalled at the fluid, black as could be. The 'Ranger method' involves sucking the MC dry, filling w/ new fluid. Slowly actuate the clutch 15-20 times. Suck it dry, new fluid, repeat. It took 7 cycles before I got the fluid to stay clear. Now I do that every spring. Apparently these internal slave cylinders are not the hot setup even if they do eliminate a clutch throwout lever.

[SJDave]

I had one of the Wilwoods leak after 300 miles; After getting it out (4 hour project) it had a big "pit" in the bore. The pit had chewed up the seal. I went with the Tilton 76 series, about $40 more per MC, no leaks in 15 years. As was stated earlier the bores are polished and Hard Anodized with a steel piston. They are beautiful!

Dave Tabor brings up a good point about losing all braking due to the balance bar setup, this is a much bigger issue that needs a solution. Anyone done it??

[Fman]

I had one of the Wilwoods leak after 300 miles; After getting it out (4 hour project) it had a big "pit" in the bore. The pit had chewed up the seal. I went with the Tilton 76 series, about $40 more per MC, no leaks in 15 years. As was stated earlier the bores are polished and Hard Anodized with a steel piston. They are beautiful!

Dave Tabor brings up a good point about losing all braking due to the balance bar setup, this is a much bigger issue that needs a solution. Anyone done it??

Dave, what bore size did you go with with the 76 series? Is this a direct bolt up with all fittings? I am on my second Wildwood MC (first one failed at 2k miles) now have 7k miles on the car. I am thinking of just swapping to the Tilton because loosing a clutch MC is a recipe for broken down and being stranded.

[JJK]

I am in the process of swapping now. The Tilton 75 series is more similar to the Wilwoods, but uses a -3 fitting instead of an AN for the pressure side. It also uses a different size hose for the reservoirs which will have to be accounted for. The 76 series has two high pressure ports, so one may need to be capped and it requires a fitting for the reservoir hose as it is different as well. Look up the specs on Tiltons website to see which you would prefer. I am going with the 75 series, but the 76 can be made to work as well.

[Smiley]

I am in the process of swapping now. The Tilton 75 series is more similar to the Wilwoods, but uses a -3 fitting instead of an AN for the pressure side. It also uses a different size hose for the reservoirs which will have to be accounted for. The 76 series has two high pressure ports, so one may need to be capped and it requires a fitting for the reservoir hose as it is different as well. Look up the specs on Tiltons website to see which you would prefer. I am going with the 75 series, but the 76 can be made to work as well.

What size bore did you go with? .75?

[JJK]

I am using 0.75 for all three as that is what I had and were fine. some use slightly different bores, which trades off the amount of pressure applied by your foot with the distance you must press the pedal.

[BUDFIVE]

JJK, the Tilton 75 series uses 3AN output vs the Wilwood is 1/8 NPT.

I’ve been looking at this too since I’m still in go-cart phase and this plus other threads have me thinking.
The 0.75 bore 75 series Tilton MC is 75-750 (75-750U for the kit). The 75-750U kit comes with a 3AN Male to 3AN Male fitting, a remote reservoir adapter and 5/16” hose, and other stuff for their reservoir. Tilton’s website has a good instruction sheet with the kit parts (and part #’s). And by the way a good video on balance bar adjustment. Summit has all the parts individually or the kit.

[JJK]

BUDFIVE, correct on all points. Meant to say -3AN instead of NPT. D-Dubya just went through this and pointed me to the adapters needed to convert the -3AN to 1/8 NPT as well as the 1/4" hoses to 5/16". Here they are for reference:
https://www.summitracing.com/parts/EAR-968703ERL
https://www.summitracing.com/parts/ICB-AN627-05-04A

[BUDFIVE]

An additional option for the input side is replace the fitting at the bottom of the FFR brake reservoirs with a Dorman 787-046D 5/16 barb X 1/8 NPT 90 deg. Then you can run the new 5/16 lines all the way to the larger, 5/16 Tilton inputs. I did mine using these today.
Link for reference https://www.oreillyauto.com/detail/c/dorman/dorman-5-16-x-1-8-inch-npt-90-degree-fuel-line-adapter/dor0/787046d?q=787-046D&pos=0

[JJK]

I completed the Wilwood to Tilton MC swap for all three master cylinders and thought I would post some pics of what I found. My car has about 750 miles and had no signs of premature failure, I just wanted to change them due to so many Wilwoods failing recently that were shipped around the same time as my kit. Last thing I wanted to deal with was a failed brake MC. First, the front seal closest to the pushrod is a bit smaller in diameter on all three pistons than the rear seal, positioned front on the left, rear in the middle, and clutch on the right. It is just barely larger than the piston diameter, so I imagine a little bit of wear and these could easily fail.

207265

They also appear smaller than what Wilwood shows for their rebuild kits.

207266

Here is a pic pf my reservoirs. For some reason, the fluid in my clutch reservoir (far left) is darker than the brake fluid in the other two. I suspect this could be due to some rubber seal failure for the clutch MC.

207267

Anyhow, the swap was not terribly fun, but I consider it preventative maintenance for a component that has recently been prone for premature failure.

[cdurbin328]

Another failure here. 1000 miles since build completion and both brake MC's have failed. A little dissapointed with FFR's tech support. Called them and was told "this is the first I'm hearing about this. You'll have to call Wilwood".
Called Wilwood and got the runaround. Was supposed to call me back and that was over a week ago. No call. I decided to just order the Tilton 75's and move on. Planning to try and tackle this job over the weekend. Not looking forward to it at all.
I really don't want to pull the dash. I'm going to pull the drivers seat and drop the fuse box. Hopefully that will give me enough room.

[Daddy O]

While the body is off at paint I decided to replace my clutch master cylinder with the Tilton unit since it is the hardest to get to once the body is on. Well, I ended up changing out both brake masters as well after what I found inside the clutch m/c and losing confidence in the Wilwood parts. Car has 650 miles on it and the clutch master was headed for failure. The fluid that came out was very dark. The piston had quite a bit of wear on the end and the bore had some linear scratches. Guessing all this aluminum wear is what was making the fluid dark. I will be reaching out to F5 and Wilwood and will also send them a link to this thread.209590209589209588209587209586

[Daddy O]

One of the Brake masters had some cylinder wear going on too. Fluid was also dark but not as bad as the clutch m/c. Thanks to all on this forum for posting your experiences. This would not have been on my radar at all other wise.209591

[Daddy O]

Wilwood got back to me. Since the parts are from 2021 when I received my kit, they are not elegible for refund, repair or replacement. They would sell me new ones at wholesale price. The feedback is that having the pedal attached too far out or too close on the pushrod can lead to the pushrod operating at an unacceptable angle leading to uneven cylinder/bore wear. I sent them a link to this thread. Nothing back from F5 yet.

[JJK]

if you are using the Wildwood pedalbox I do not understand how the pedal height would affect the angle of the pushrod engagement.

[Daddy O]

This is the response from Wilwood “ if the pushrod is set so long that the pedal arm is at an angle at the start, or too short so it is at an angle when fully pressed.”

[Mike.Bray]

So the Wilwood-designed pedal box is the issue? That's a bunch of crap. The pedal is on a pivot so there's never going to be a perfect linear motion of the rod/cylinder. The issue is the fundamental design of the piston and the plain machined bore of the master cylinder. And to some degree the quality, or lack of quality, of the aluminum castings. The Tilton overcomes this with a better piston design and hard anodizing the bore.

I also sent this thread to Factory Five a few weeks ago and they responded that they would look into it but haven't heard back from them since. To me it's pretty scary with the pedal box design the way it is and a single MC failure can cause complete brake failure.

[burchfieldb]

So the Wilwood-designed pedal box is the issue? That's a bunch of crap. The pedal is on a pivot so there's never going to be a perfect linear motion of the rod/cylinder. The issue is the fundamental design of the piston and the plain machined bore of the master cylinder. And to some degree the quality, or lack of quality, of the aluminum castings. The Tilton overcomes this with a better piston design and hard anodizing the bore.

I also sent this thread to Factory Five a few weeks ago and they responded that they would look into it but haven't heard back from them since. To me it's pretty scary with the pedal box design the way it is and a single MC failure can cause complete brake failure.

I am an agreement with you on this. As an engineer this sounds like an excuse for a poor design and for a company that does not want to own up to it. Cheaper to deny the problem than to fix it. If properly designed, you would not be able to adjust it to the point that you would have the potential of failure, especially on a safety critical item.

[Mike.Bray]

Some recent chatter about more Wilwood MC failures got me thinking, I had emailed Dave L. at Factory Five back in December which he acknowledged but then went quiet so I followed up today. Dan replied that Factory Five engineering had brought this to Wilwood's attention but he did not know what if anything had transpired since then. Since issues with Wilwood master cylinders date back decades I doubt if it's being addressed but we can hope.

[M22_COBRA]

Was going to add this to my build thread but I'll post here.
I had mine go bad right out of the box. I took it apart and this is what I saw. I do not have a tool to measure surface finish but I'm not really sure this is ra4-16. Looks pretty rough, and you can see some fissures which may be porosity. But I'm not a metallurgist so that's not really my Lane. You can see one pitt in the chamfer but that shouldn't effect sealing. I checked the bore and the o-ring size and it checks out on the Parker website to be to spec.
210934210935210936210937

[Mike.Bray]

Not only is that a horrible surface finish for a hydraulic cylinder bore but just machining cast aluminum I don't think is the best idea. The Tilton's are hard anodized, the bores are smooth and very hard. Night and day difference.

[cv2065]

Not only is that a horrible surface finish for a hydraulic cylinder bore but just machining cast aluminum I don't think is the best idea. The Tilton's are hard anodized, the bores are smooth and very hard. Night and day difference.

I did swap out my clutch MC for the Tilton as it gets the most abuse. But I will say that the installation is not as easy with the Tilton. The MC hose caps are extremely tight and a bear to get fully seated, even with a little grease. You would need a screwdriver or something to pop it off once all the way down. One suggestion is to have the hose cap cocked off to one side as if it's straight over the nut, you won't be able to get a wrench on it without popping the cap off, which would be really difficult in a completed car. You also cannot swivel them at that point, so you need to ensure that it's definitely pointed in the right direction. There is no flat spot for a wrench on the threaded rod, so you just have to use your fingers to install into the clevis. Might prove difficult to remove once the footbox is closed up. Also, not a huge fan of the metal hold down spring clip thingy. It's bulky but I don't think you'd have to worry about it falling off once seated, even without a clip. It also doesn't come with a locking nut and you'll need a 5/16-24 'thin' nyloc to secure on the bottom as the flange is thicker with the bottom bracket.

All that said, definitely more robust on the outside vs. the Wilwood, but I'll be keeping the brake masters as is.

[RogerRoger88]

I'm at the point in my build where I'm ready to purchase the Tilton. I see that both the 75 and 76 work. My question is which one do you all choose and why?

[Mike.Bray]

I'm at the point in my build where I'm ready to purchase the Tilton. I see that both the 75 and 76 work. My question is which one do you all choose and why?

I used the 76 series which use banjo fittings.

https://www.imagecoast.com/images/MichaelBray1/20220623151757mediumrotated.jpg

To maintain the Factory Five type design you would use the 75 series.

Note that FFR supply all master cylinders in 3/4" bore. If you're going to change them out for the better Tiltons you should do the calculations for optimum bore sizes. I ended up with three different ones.

[F500guy]

I used the 75 series because it was closer to the wilwood and did not need to redo any brake lines, see my build thread Post 123 for pictures.

[OB6]

Either one will work, as Mike and F500Guy said. I used the 75.

Most importantly, the internals are identical, and I confirmed that with Tilton.

[RogerRoger88]

Thanks for the responses! And Mike, your setup is a work of art.

[dallas_289]

Well, add me to the failed Wilwood MC club. My clutch pedal went completely limp last weekend, luckily, as I was leaving the driveway to go for a drive. I felt the MC slowly losing pressure eventually bottoming out completely, fairly confident it's the MC.

I'm at ~1,800 miles using MCs from my kit delivered in fall 2022. I just ordered Tilton MCs from Summit. I wish I had done this back during the build, as I saw multiple posts highlighting concerns around Wilwood MCs.

I'm going to tackle the clutch MC this weekend and, eventually, the brake MCs. I appreciate all the details in this thread (JJK and others) saving me a lot of research on converting to Tilton MCs.

[OB6]

Glad it was the clutch and not the brake MC. Good move to just replace all three.

[Mike.Bray]

Well, add me to the failed Wilwood MC club. My clutch pedal went completely limp last weekend, luckily, as I was leaving the driveway to go for a drive. I felt the MC slowly losing pressure eventually bottoming out completely, fairly confident it's the MC.

I'm at ~1,800 miles using MCs from my kit delivered in fall 2022. I just ordered Tilton MCs from Summit. I wish I had done this back during the build, as I saw multiple posts highlighting concerns around Wilwood MCs.

I'm going to tackle the clutch MC this weekend and, eventually, the brake MCs. I appreciate all the details in this thread (JJK and others) saving me a lot of research on converting to Tilton MCs.

I guess if there's anything lucky so far it is the clutch MC, being used the most, that usually fails first saving you from catastrophic brake failure. It only takes one brake MC failure to lose all braking.

Have you reported this to Factory five?

[Windsorpower]

If you are going to replace the Wilwood clutch MC with the Tilton, you’ll want this one. Forte includes a 13/16” MC with his kit.

https://www.summitracing.com/parts/TIL-75-812U

Do you know if the Forte braided hydraulic line is -3 AN? If it indeed is, then I think I just need a -3AN/-3AN double male adapter to get the Tilton MC connected to the Forte line.

[dallas_289]

I'm back after messing with replacing the MCs over the last month. I'm a bigger guy with a bad back, so getting into the foot box was not fun, but doable. I broke up removing and replacing over the course of a couple of weekends.

The failure was indeed the clutch MC; pulling it apart, it appears the inner seal failed (caught it before it started leaking). The replacement Tilton MCs are great - maybe it's a placebo effect but the brakes feel significantly better and clutch slightly smoother.

For anyone building, just throw out the Wilwood MCs and start with the Tiltons. For anyone who has to replace them after the body is on, remove/replace the MCs with the car on the ground, going in through the cockpit (go in from under the dash).

[Daddy O]

Hi Dallas,

Did you have a chance to let F5 know about the failure? Has anybody gotten any more feedback from them?

[Windsorpower]

Hi Dallas,

Did you have a chance to let F5 know about the failure? Has anybody gotten any more feedback from them?

Crickets. These Tilton units seem cheap at first glance. The MC caps are infuriating and the lack of the 1/4 inch flat spot on the pushrod makes adjustment nearly impossible.

[tundra2050]

Does the Tilton clutch MC kit come with everything needed, minus the chrome reservoir? Is hard line recommended over braided to the throw out bearing lines?

[F500guy]

Depending on when you are changing to the Tilton you may need a fitting to tie into the brake line, the end of the Tilton accepts AN or banjo type fitting. I used a banjo fitting for the clutch cable and used the braided pre-made hose. I got a AN-to-NPT fitting for the front/rear master cylinders so they tied into my existing lines. The reservoir, depending on what what model you got will have a threaded fitting or a cap with a hose barb. The hose size is larger than the hose size of the tilton.

[Jeff Kleiner]

... The MC caps will are infuriating.

Use a 76 Series rather than the 75. The 75 uses a clamp on reservoir or cap to change to a barb connection for the feed whereas the 76 is made to accept a banjo fitting or screw in barb connection.

Jeff

[Mike.Bray]

Use a 76 Series rather than the 75. The 75 uses a clamp on reservoir or cap to change to a barb connection for the feed whereas the 76 is made to accept a banjo fitting or screw in barb connection.

Jeff

I did the 76 series with banjo adapters to AN.

221502221503

[tundra2050]

Thanks F500guy, Jeff and Mike. Mike, I like your setup. I saw in another post you'd go with AN braided hose to the bulkhead. I like that idea. Is it braided to the reservoirs? I also like the AN fittings. Does your hard lines run to the FF supplied hard lines? How long of a hard line do you recommend to run for the clutch? What size banjo fittings/bolts did you use?

I also wonder why FF still uses the Wilwoods and not the Tiltons if there are this many failures?

I'm still waiting on the car. It was supposed to have been completed this past Saturday. I'm still new to this so please forgive if I need extra clarification.

Thanks again gents!

[edwardb]

...I also wonder why FF still uses the Wilwoods and not the Tiltons if there are this many failures?...

At the risk of opening a can of worms and getting flamed, I'll respond. There are multiple threads on this topic, typically from a few vocal forum members. That's how social media often works. Some reports turn into all must be bad. I'm not defending Wilwood and perhaps the Tiltons are better. But many have used Wilwoods without issue, and as usually the case that doesn't get reported as loudly. That's my core message. I've used them in five builds. My current Coupe with Wilwoods is in its fifth season and 10K miles. I did have one a while back that dripped slightly when it was first installed. Traced to a defective O-ring. Probably not made by Wilwood and could happen with any brand IMO. Replaced the O-ring and put into service with no issues afterward. I too would be interested knowing what Factory Five's position on this subject might be. But (call me naive) if there were as many issues as some suggest, I think they would address it. They have in the past with other suppliers. Especially since it's safety related. Think Bilstein. Plus, let's be honest, they are a core supplier also with pedal boxes, brakes, etc. I'm a data and statistics guy and haven't seen any yet. Having said that, I am giving a Tilton MC a try on the hydraulic clutch in my current Mk5 Roadster build. I'm positive I'll get responses. Flame suit on.

https://thefactoryfiveforum.com/attachment.php?attachmentid=221559&d=1763207085

[rich grsc]

Perfect response

[Mike.Bray]

Thanks F500guy, Jeff and Mike. Mike, I like your setup. I saw in another post you'd go with AN braided hose to the bulkhead. I like that idea. Is it braided to the reservoirs? I also like the AN fittings. Does your hard lines run to the FF supplied hard lines? How long of a hard line do you recommend to run for the clutch? What size banjo fittings/bolts did you use?

I also wonder why FF still uses the Wilwoods and not the Tiltons if there are this many failures?

I'm still waiting on the car. It was supposed to have been completed this past Saturday. I'm still new to this so please forgive if I need extra clarification.

Thanks again gents!

I ran -4 hard lines from my Scott's reservoirs to bulkhead fittings in the front of the footbox. I'm kind of an AN stainless hardline geek. And I could never make an SAE double flare to same my life.

221573

Out of the Tilton master cylinders I ran -3 AN hard lines for as much of the clutch and brake systems as I could. There's a link in my signature line detailing my experience with AN stainless lines.

As for why FFR use Wilwood, I can only assume they have a supplier agreement with them and in their eyes the failure rate is acceptable which is mind boggling considering we're talking about master cylinders. But that's their decision.

[Mike.Bray]

At the risk of opening a can of worms and getting flamed, I'll respond. There are multiple threads on this topic, typically from a few vocal forum members. That's how social media often works. Some reports turn into all must be bad. I'm not defending Wilwood and perhaps the Tiltons are better. But many have used Wilwoods without issue, and as usually the case that doesn't get reported as loudly. That's my core message. I've used them in five builds. My current Coupe with Wilwoods is in its fifth season and 10K miles. I did have one a while back that dripped slightly when it was first installed. Traced to a defective O-ring. Probably not made by Wilwood and could happen with any brand IMO. Replaced the O-ring and put into service with no issues afterward. I too would be interested knowing what Factory Five's position on this subject might be. But (call me naive) if there were as many issues as some suggest, I think they would address it. They have in the past with other suppliers. Especially since it's safety related. Think Bilstein. Plus, let's be honest, they are a core supplier also with pedal boxes, brakes, etc. I'm a data and statistics guy and haven't seen any yet. Having said that, I am giving a Tilton MC a try on the hydraulic clutch in my current Mk5 Roadster build. I'm positive I'll get responses. Flame suit on.

https://thefactoryfiveforum.com/attachment.php?attachmentid=221559&d=1763207085

Okay I'll bite Paul and fan the flames:cool: You're an aviation guy where every part has a reliability rating, usually 3-4 nines if I remember correctly? Depends on the flight safety rating of the part. I would think on a car the master cylinders need to have a fairly high reliability rating, and they do. OEM master cylinders do fail of course but it is rare, usually they wear out. Got my first car in 1976 and have had over 50 since then and I've never had a MC failure. So we can agree OEM master cylinder failures are very rare?

I was first warned about Wilwood master cylinders 25-30 years ago when I had my shop. I examined one back then and didn't like what I saw with the porosity in the aluminum casting, surface finish of the (non-plated) bore, and the short piston design. To me the design is lacking as well as the quality. That was my opinion back then and today it is the same.

Now, if we only take into account reported failures on this forum it seems to be more than a few. Multiply by 10 for the unreported failures. Some Wilwoods have failed right out of the box. Is this acceptable? I do agree with you that the odds are in your favor, same for Russian roulette with only one bullet in the chamber. Or driving without insurance. So it's all about what is an acceptable risk and the odds right?

If the clutch MC fails you're walking. If a brake MC fails I'll agree with you you do have some braking in the other MC but it will be limited. Depending on how fast you're going and the circumstances you could be okay.

To each his own and the odds are in your favor, I just don't like the odds the Willwoods give vs. the better Tiltons.


https://youtu.be/Hz4AlAt7DJ8?si=QorIKrMoLNrEmruP

[Papa]

I watched the video Mike posted. Interestingly, Wilwood has a very specific caution in their install instructions about ensuring the push rods are not pushing at an angle, which would likely produce the wear that the guy in the video showed.

Warning – If the Master cylinder pushrods are not straight, it will cause side loads on the master cylinder
which will lead to a master cylinder failure.

I wonder how many Wilwood failures are caused by faulty installation vs. defective parts? I'm not saying that Tilton isn't a superior product, but just that Wilwood MCs are likely more than adequate for most of our use cases if they are installed properly. Sure, there will be defects in all products, and I think the pandemic has shown us a lot of quality control escapes across many industries that continue to linger even years after the height of the pandemic.

[Mike.Bray]

Warning – If the Master cylinder pushrods are not straight, it will cause side loads on the master cylinder
which will lead to a master cylinder failure.

Being simple minded I would think since the Wilwood master cylinders are installed in a Wilwood pedal bracket this would not be an issue??

Still doesn't explain failures right out of the box.

[tundra2050]

I watched the video Mike posted. Interestingly, Wilwood has a very specific caution in their install instructions about ensuring the push rods are not pushing at an angle, which would likely produce the wear that the guy in the video showed.

Warning – If the Master cylinder pushrods are not straight, it will cause side loads on the master cylinder
which will lead to a master cylinder failure.

I wonder how many Wilwood failures are caused by faulty installation vs. defective parts? I'm not saying that Tilton isn't a superior product, but just that Wilwood MCs are likely more than adequate for most of our use cases if they are installed properly. Sure, there will be defects in all products, and I think the pandemic has shown us a lot of quality control escapes across many industries that continue to linger even years after the height of the pandemic.

Let's say the installation is to spec. Is it possible the push rods are shifting over time due to the pedal box setup with the adjustable balance bar? Sorry to open this can of worms. I love the responses because I'm learning a lot. I've never had to replace a MC on a car. I know clutches can occasionally go out but that's rare with normal driving, but brake failure? Never experienced that over hundreds of thousands of miles.

[Papa]

Being simple minded I would think since the Wilwood master cylinders are installed in a Wilwood pedal bracket this would not be an issue??

Still doesn't explain failures right out of the box.

It's very possible to get the push rods at an angle with the Wilwood pedal box. Before the push rods are threaded in, simply spin the clevises on the balance bar to change the spacing between them. Out of the box failures are quality escapes. They don't design them to fail, they fail because of quality control issues either in the machining or assembly process.

[Mike.Bray]

It's very possible to get the push rods at an angle with the Wilwood pedal box. Before the push rods are threaded in, simply spin the clevises on the balance bar to change the spacing between them. Out of the box failures are quality escapes. They don't design them to fail, they fail because of quality control issues either in the machining or assembly process.

Sorry Dave, then I would say what about the clutch? Can it be misaligned also? Those seem to have the most failures no doubt as it is cycled the most.

As a design engineer I think the Wilwood design is sub-par, especially when compared to the Tilton. Then throw in quality control issues on top of that.....Nope, not for me.

[Papa]

Sorry Dave, then I would say what about the clutch? Can it be misaligned also? Those seem to have the most failures no doubt as it is cycled the most.

As a design engineer I think the Wilwood design is sub-par, especially when compared to the Tilton. Then throw in quality control issues on top of that.....Nope, not for me.

I don't have any data on numbers of failures, so I can't really make any quantitative statements. I just wanted to make a point that there are lots of opportunities to help parts fail on these builds and that perhaps some of the failures are self-inflicted by the builders themselves. Now I'll need to put on my fire suit. :p

My Wilwood MC's on my MK4 are my only hands-on experience and they have not shown any issues in eight years. I'll just leave it at that and bow out now.

Dave

[Bill Elliott]

I don't have any data on numbers of failures, so I can't really make any quantitative statements. I just wanted to make a point that there are lots of opportunities to help parts fail on these builds and that perhaps some of the failures are self-inflicted by the builders themselves. Now I'll need to put on my fire suit. :p

My Wilwood MC's on my MK4 are my only hands-on experience and they have not shown any issues in eight years. I'll just leave it at that and bow out now.

Dave

So this is what i would like to see more of,,,, people chiming in saying what success they have had with Wilwood MC's. Eight years is remarkable compared to all the bad news we have heard.

[PMD24]

I installed Tilton 75s. Had I known more at the time I would have gone with the 76's for the banjo style connections which are very friendly for hardline routing. Turns out I was able to use banjos on the output side using some short banjo bolts from Inline Tube. You have to be careful to not bottom out the bolt and end up with inadequate crush on the washer.

Pat