CBC is TRASH! Need recommendations

[nalinc23]

So as a new F80 owner I'm researching Crank Hub options. Local shop is suggesting Insane Performance 2 Pin and then Kies CBC as peace of mind. I would assume as long as installed properly this would be a good setup and quite safe? Or is it worth going for the 4 pin + CBC? Or just ditching the CBC all together? Figured I'd raise the question since quite some time has passed on this thread.

[MisterF80M3]

I just saw this thread, made me immediately get an endoscope camera and check my CBC. I got my CBC installed for 5 years, 40k miles. I track my car multiple times per season and have switched between stage 2, 91 tune and custom tune e85 tune on just CBC only and it's holding up fine. My friend also checked his CBC and got it installed a few years ago with no issues. I attached pictures of my CBC and also my friend's.

Personally, it looks like the newer batch of CBC bolts is defective.

[Wanted_M]

Have you taken it off previously, I see some shinny markings on the CBC where your washer resides. On the second pic, your washer is not sitting flush on CBC at the 11 o' clock position. Please take a peek at that, some movement is happening there, those CBC edges should not be shinny/scrapping like that.

[M3SQRD]

Originally Posted by Wanted_M

Have you taken it off previously, I see some shinny markings on the CBC where your washer resides. On the second pic, your washer is not sitting flush on CBC at the 11 o' clock position. Please take a peek at that, some movement is happening there, those CBC edges should not be shinny/scrapping like that.

A lot of the washers are biased in the same direction under the head of the SHCS. You’d expect a more random arrangement of washer positions during installation (or all washers biased vertically downward due to gravity). So it does appear the SHCSs are moving relative to their washer. Even if the majority of the failures are due to over/under torquing of the SHCS, there still are failures due to CBC material choose and/or poor quality SHCS. So regardless of how it failed, why would you risk it? I don’t believe the SCH is a major issue and I’ve been tracking my car since 2016, with both stock and GTS ecu tunes, and I’ve never once thought about a SCH failure while on track.

[Wanted_M]

Originally Posted by M3SQRD

A lot of the washers are biased in the same direction under the head of the SHCS. You’d expect a more random arrangement of washer positions during installation (or all washers biased vertically downward due to gravity). So it does appear the SHCSs are moving relative to their washer. Even if the majority of the failures are due to over/under torquing of the SHCS, there still are failures due to CBC material choose and/or poor quality SHCS. So regardless of how it failed, why would you risk it? I don’t believe the SCH is a major issue and I’ve been tracking my car since 2016, with both stock and GTS ecu tunes, and I’ve never once thought about a SCH failure while on track.

To each's own bro, I have Vargas combo installed and worry free no matter what I throw at it. My CBC does not show that wear as all washers are all centered nicely. Install error, they should have looked at it with a borescope and centered washers before torquing bolts, that's what the shop I used did.

[MisterF80M3]

Originally Posted by Wanted_M

Have you taken it off previously, I see some shinny markings on the CBC where your washer resides. On the second pic, your washer is not sitting flush on CBC at the 11 o' clock position. Please take a peek at that, some movement is happening there, those CBC edges should not be shinny/scrapping like that.

I never took it off. I took a closer look at it today. I don't see the shiny part. The endoscope camera has a bright light shining onto the CBC. It might give the impression that there are wear marks on the CBC when it doesn't.

[Wanted_M]

Originally Posted by MisterF80M3

I never took it off. I took a closer look at it today. I don't see the shiny part. The endoscope camera has a bright light shining onto the CBC. It might give the impression that there are wear marks on the CBC when it doesn't.

.
Ok, I look at gas turbine, steam turbine borescope, repairs and analyze what I see, not by choice lol. See my input/comments below but it's up to you, just trying to help.

[M3SQRD]

Originally Posted by Wanted_M

To each's own bro, I have Vargas combo installed and worry free no matter what I throw at it. My CBC does not show that wear as all washers are all centered nicely. Install error, they should have looked at it with a borescope and centered washers before torquing bolts, that's what the shop I used did.

I was agreeing with you on the pictures showing the SHCSs shifting on the washers, and the washers slipping on the CBC. Yes, we disagree on SCH.

[hC1001]

Originally Posted by Wanted_M

.
Ok, I look at gas turbine, steam turbine borescope, repairs and analyze what I see, not by choice lol. See my input/comments below but it's up to you, just trying to help.

Interesting. I did some googling and those rub marks you highlighted are actually machined aluminum to give space for the round washers. I dont see anything to be concerned about. Please see pic of a uninstalled CBC:

[Wanted_M]

Originally Posted by hC1001

Interesting. I did some googling and those rub marks you highlighted are actually machined aluminum to give space for the round washers. I dont see anything to be concerned about. Please see pic of a uninstalled CBC:

Yes, it could be the reflection of the flash reflecting that silver, I looked at mine and there's no silver anywhere or discoloration with a borescope today even with light on. That second picture, you can clearly see the washer not centered and bent but what do I know, I'm just a dumb engineer

[MisterF80M3]

Originally Posted by Wanted_M

.
Ok, I look at gas turbine, steam turbine borescope, repairs and analyze what I see, not by choice lol. See my input/comments below but it's up to you, just trying to help.

I'm no engineer but I deal with machinery repair on a somewhat basis. I feel like this is blown way out of proportion. We have people here in this thread with bolts completely shearing off, missing the majority of their bolts on their CBC, major scoring on the CBC, and we are nitpicking washers being misaligned? Stop fear-mongering.

Don't forget what other people in this thread are dealing with:

[hC1001]

Originally Posted by Wanted_M

Yes, it could be the reflection of the flash reflecting that silver, I looked at mine and there's no silver anywhere or discoloration with a borescope today even with light on. That second picture, you can clearly see the washer not centered and bent but what do I know, I'm just a dumb engineer

You can see other parts of the CBC has overexposure from the light and there should also be wear marks in the same direction creating an oblong shape but there isnt. The rub marks you highlighted is isolated to the machined area only.

As for the "bent" washer, its hard to get a definitive answer whether its actually sitting flat or not. If the washer got caught inside the bolt slot of the CBC and tightened down, it wont sit flush with the surface. Thats more of an installer error than a product defect. You cant really see anything when installing the bolts so i can see it happening.

[Wanted_M]

Originally Posted by hC1001

Thats more of an installer error than a product defect. You cant really see anything when installing the bolts so i can see it happening.

That's my point, never said it was a product defect. Good luck, not my car, if it was me, I'd take a second look but whatever. I've said enough.

[Wanted_M]

Originally Posted by MisterF80M3

I'm no engineer but I deal with machinery repair on a somewhat basis. I feel like this is blown way out of proportion. We have people here in this thread with bolts completely shearing off, missing the majority of their bolts on their CBC, major scoring on the CBC, and we are nitpicking washers being misaligned? Stop fear-mongering.

Don't forget what other people in this thread are dealing with:

If you feel I'm picking on you I'm not, I'm pointing out an install deficiency that could cause a problem and that's it, you do what you want. The pics you've posted are most likely due too over torqued bolts which washer will dig into the soft material and of course it's going to fail, whoever installed it should have known better. Know the material you're dealing with and what the torque values are, that goes for every nut and bolt from a car to a rocket. The material hardness is key, and that picture speaks highly of why TQ values are important which more than likely exceeded VTT specs.

With all that said:
1. What can we all learn from this as a group?
2. What's the best practice that we can offer folks reading this thread and looking into this upgrade?
3. Anything else we can think of when installing the CBC? (Type of Loctite to be used, TQ spec, have shop take a pic of CBC before you drive away).

[theweebabySeamus]

Originally Posted by Wanted_M

If you feel I'm picking on you I'm not, I'm pointing out an install deficiency that could cause a problem and that's it, you do what you want. The pics you've posted are most likely due too over torqued bolts which washer will dig into the soft material and of course it's going to fail, whoever installed it should have known better. Know the material you're dealing with and what the torque values are, that goes for every nut and bolt from a car to a rocket. The material hardness is key, and that picture speaks highly of why TQ values are important which more than likely exceeded VTT specs.

With all that said:
1. What can we all learn from this as a group?
2. What's the best practice that we can offer folks reading this thread and looking into this upgrade?
3. Anything else we can think of when installing the CBC? (Type of Loctite to be used, TQ spec, have shop take a pic of CBC before you drive away).

Install tip: I installed FOUR capless threaded screws in place of their respective screws removed, in a square pattern, then pulled the remaining four and placed the CBC over that. Made it easier to line up the CBC and easier to figure out which screws were being reinstalled without having visual on it.

[MisterF80M3]

Originally Posted by Wanted_M

If you feel I'm picking on you I'm not, I'm pointing out an install deficiency that could cause a problem and that's it, you do what you want. The pics you've posted are most likely due too over torqued bolts which washer will dig into the soft material and of course it's going to fail, whoever installed it should have known better. Know the material you're dealing with and what the torque values are, that goes for every nut and bolt from a car to a rocket. The material hardness is key, and that picture speaks highly of why TQ values are important which more than likely exceeded VTT specs.

With all that said:
1. What can we all learn from this as a group?
2. What's the best practice that we can offer folks reading this thread and looking into this upgrade?
3. Anything else we can think of when installing the CBC? (Type of Loctite to be used, TQ spec, have shop take a pic of CBC before you drive away).

I feel like you are overanalyzing. Until bolts are shearing off or CBC is showing signs of wearing, I'm not even going to lose sleep over washers looking misaligned.

[5ABIVT]

Will post an image i took of mine as i am doing plugs and remembered to slide my phone down and take a look. I installed at I believe 100k kms and I'm at 140 now. stage 2 91 bm3 tune with usual bolt ons, 16 6m and yes I do drive it hard when opportunity presents itself and shift at the limiter.

Personally, From the start I've looked at this thread for a while and cant help but feel people are failing to consider than if there is movement in the bolts or cbc.. perhaps it's because it's doing its job. Most including me are installing these when the vehicles are used for some time and there's no knowing if the bolt has already loosened any amount already.

From what ive gathered over the years my belief is firmly that no friction disc is equal. Just like sandpaper... there's going to be some high spots and variance in the diamond dust or whatever they are using. This is why some cars have held to 600 hp fine and others spin stock. its a diamond dust lottery. The ultimate solution still is a hub fix and my personal favorites are the large tab types like precision dynamics and Gintani.

uploaded photo ...

[FrankMstein]

Warming the car is more important and more variable than the controlled production of a diamond dust application of a friction washer, given its human controlled. Also, some spin w/o splitting the washer.