Crank Bolt Capture

[Chris@VargasTurboTech]

Correction, one V1 installed correctly with CBC has slipped. Zero V2's, they're far more aggressive and backed by a warranty. It's simply a better design than a pinned hub.

[QMoney]

Does anyone know of a shop that will do this in Broward County here in SoFlo?

[718ZCP]

Looking to go VTT bolt capture on my 18 zcp. Intake catless Downpipe and JB4 map 2. Shouldn’t be making over 500 wheel on pump , do you guys feel the bolt capture would help any if running this setup? Thanks In advance

[MJ6]

Originally Posted by 718ZCP

Looking to go VTT bolt capture on my 18 zcp. Intake catless Downpipe and JB4 map 2. Shouldn’t be making over 500 wheel on pump , do you guys feel the bolt capture would help any if running this setup? Thanks In advance

In a word, yes.
And just to be clear, to date there is no documented instance of an S55 engine (outside of money-shifting or other catastrophic engine failures) spinning the hub with a CBC installed other than second hand accounts where someone's friend had a roommate who's Uncles cousin had it happen once.

[hellokitty]

Originally Posted by MJ6

In a word, yes.
And just to be clear, to date there is no documented instance of an S55 engine (outside of money-shifting or other catastrophic engine failures) spinning the hub with a CBC installed other than second hand accounts where someone's friend had a roommate who's Uncles cousin had it happen once.

Good to know.

[Chris@VargasTurboTech]

Eh, I guess I'll put on my bad-guy costume and state that there are cases of slipped CBC only engines, but none on this forum and there are a small but enthusiastic group that thinks this means there are zero that ever were, period, end of story. In full disclosure some also think anything to the contrary was fabricated to sell more hubs, which is silly. The tail doesn't wag the dog, the design effort and understanding was done to solve a real problem that's quite a pain to deal with if it happens to you.

I've seen a few. It is my position that I'd have seen more except most people going for 2x+ the factory rated crank horsepower at the wheels tend to fool around less.

Those that say there are no CBC only slips will say that the hub vendors are peddling fear. Nope. 20+ years as a mechanical engineer, there are 2 mechanisms for hub slip. Bolt vibrating loose (fix w/CBC) and overpowering design torque limit (fix with better hub). There are a lot of factors making data noisy and hard to predict where the line in the sand is. I offer this; in the past year I haven't seen a CBC only slip at/under 600 whp. CBC reduces the risk, CBC + hub retires the risk. Those are the facts.

Trying to find middle ground here, if it were my personal car and I didn't have access to the shop what would I do? I'd put a CBC on the damned car from day 1. It's inexpensive, fairly easy to install, and helps quite a bit. If I stayed on pump gas and stock turbos that's probably all I'd do, most likely anyway. It's hard to get away from the allure of E85 though, and probably somewhere before I went with upgraded turbos and E85 I'd do the hub. If I were going to stick to pump gas I may hedge my bets.


Chris

[hellokitty]

Originally Posted by Chris@VargasTurboTech

Eh, I guess I'll put on my bad-guy costume and state that there are cases of slipped CBC only engines, but none on this forum and there are a small but enthusiastic group that thinks this means there are zero that ever were, period, end of story. In full disclosure some also think anything to the contrary was fabricated to sell more hubs, which is silly. The tail doesn't wag the dog, the design effort and understanding was done to solve a real problem that's quite a pain to deal with if it happens to you.

I've seen a few. It is my position that I'd have seen more except most people going for 2x+ the factory rated crank horsepower at the wheels tend to fool around less.

Those that say there are no CBC only slips will say that the hub vendors are peddling fear. Nope. 20+ years as a mechanical engineer, there are 2 mechanisms for hub slip. Bolt vibrating loose (fix w/CBC) and overpowering design torque limit (fix with better hub). There are a lot of factors making data noisy and hard to predict where the line in the sand is. I offer this; in the past year I haven't seen a CBC only slip at/under 600 whp. CBC reduces the risk, CBC + hub retires the risk. Those are the facts.

Trying to find middle ground here, if it were my personal car and I didn't have access to the shop what would I do? I'd put a CBC on the damned car from day 1. It's inexpensive, fairly easy to install, and helps quite a bit. If I stayed on pump gas and stock turbos that's probably all I'd do, most likely anyway. It's hard to get away from the allure of E85 though, and probably somewhere before I went with upgraded turbos and E85 I'd do the hub. If I were going to stick to pump gas I may hedge my bets.


Chris

Thanks Chris.

I plan on staying on stage 1 ACN 91. I flashed it a couple of days ago, did some test pulls and that was that. Going to get the CBC installed this week

[Nothing]

Originally Posted by Chris@VargasTurboTech

Eh, I guess I'll put on my bad-guy costume and state that there are cases of slipped CBC only engines, but none on this forum and there are a small but enthusiastic group that thinks this means there are zero that ever were, period, end of story. In full disclosure some also think anything to the contrary was fabricated to sell more hubs, which is silly. The tail doesn't wag the dog, the design effort and understanding was done to solve a real problem that's quite a pain to deal with if it happens to you.

I've seen a few. It is my position that I'd have seen more except most people going for 2x+ the factory rated crank horsepower at the wheels tend to fool around less.

Those that say there are no CBC only slips will say that the hub vendors are peddling fear. Nope. 20+ years as a mechanical engineer, there are 2 mechanisms for hub slip. Bolt vibrating loose (fix w/CBC) and overpowering design torque limit (fix with better hub). There are a lot of factors making data noisy and hard to predict where the line in the sand is. I offer this; in the past year I haven't seen a CBC only slip at/under 600 whp. CBC reduces the risk, CBC + hub retires the risk. Those are the facts.

Trying to find middle ground here, if it were my personal car and I didn't have access to the shop what would I do? I'd put a CBC on the damned car from day 1. It's inexpensive, fairly easy to install, and helps quite a bit. If I stayed on pump gas and stock turbos that's probably all I'd do, most likely anyway. It's hard to get away from the allure of E85 though, and probably somewhere before I went with upgraded turbos and E85 I'd do the hub. If I were going to stick to pump gas I may hedge my bets.


Chris

As someone that has owned my '16 M3 since new, I have sat back and tried to let the more courageous owners tune and be the guinea pigs while I sat back and watched.

Originally, I saw a lot of debate about the CBC vs hub replacement and honestly, it felt like most of the guys running any mods have opted for the full hub replacement. Are you seeing this differently? Have you had a lot of experience with the CBC and 500-600hp cars? I'd love to go to a Stage 2 tune and maybe play around with the ethanol options that the latest BM3 update has given to us. But even then a Stage 2 car on E30 is hovering just under 600 whp. I also track this car once or twice a year and need that peace of mind.

Thanks for your input.

[MJ6]

Originally Posted by Nothing

As someone that has owned my '16 M3 since new, I have sat back and tried to let the more courageous owners tune and be the guinea pigs while I sat back and watched.

Originally, I saw a lot of debate about the CBC vs hub replacement and honestly, it felt like most of the guys running any mods have opted for the full hub replacement. Are you seeing this differently? Have you had a lot of experience with the CBC and 500-600hp cars? I'd love to go to a Stage 2 tune and maybe play around with the ethanol options that the latest BM3 update has given to us. But even then a Stage 2 car on E30 is hovering just under 600 whp. I also track this car once or twice a year and need that peace of mind.

Thanks for your input.

For what it's worth, I'll be having turbos and injectors installed in June along with an E85 flex-fuel tune and only plan on keeping the CBC. If it spins, I'll be the first to report back on how tasty I find the crow if there's crow to be had.

[M 4 FUN]

Originally Posted by kingofqueenz788

i work as a windshield installer and i do countless 3 series cars and more then half the windshield motor bolts is not even screwed in im talking about sticking up causing play in the wipers. with seeing a thing like this just not even screwed in makes me think more and more abt my hub. also more power puts a lot of stress on the tiny oem sprockt design. i am going with a fix soon also what one do u guys recommend and have experience with

Can you explain how more power put more load on the sprockets?

[Chris@VargasTurboTech]

Originally Posted by Nothing

As someone that has owned my '16 M3 since new, I have sat back and tried to let the more courageous owners tune and be the guinea pigs while I sat back and watched.

Originally, I saw a lot of debate about the CBC vs hub replacement and honestly, it felt like most of the guys running any mods have opted for the full hub replacement. Are you seeing this differently? Have you had a lot of experience with the CBC and 500-600hp cars? I'd love to go to a Stage 2 tune and maybe play around with the ethanol options that the latest BM3 update has given to us. But even then a Stage 2 car on E30 is hovering just under 600 whp. I also track this car once or twice a year and need that peace of mind.

Thanks for your input.

It's a sliding scale between daily driver with a tune all the way to race car. Closer you get to a race car -tracking/strip/course, turbos, high octane fuel and the tune to use it- the more likely customers are to put a hub in. Lots of guys did/do it same time as turbo install. It's just about identifying and balancing risk at a level you're comfortable with. If I were racing and on ethanol to me that's enough to push my risk acceptance over the edge and I would put a hub in, simply because once you're on the track things get real aggressive real fast -or at least they can, depending on how you drive the car. Just my 2c.

Chris

[rmanm4]

Originally Posted by M 4 FUN

Can you e4xplain how more power put more load on the sprockets?

Sprockets have friction plates between them so if your engine has over 600-650 torque it will overcome the friction between the sprockets. It wont matter if the bolt holds with a CBC, the friction plate can be overpowered to slip timing!

[MJ6]

Originally Posted by rmanm4

Sprockets have friction plates between them so if your engine has over 600-650 torque it will overcome the friction between the sprockets. It wont matter if the bolt holds with a CBC, the friction plate can be overpowered to slip timing!

Which is technically true, the issue is that we have no idea at what load the friction washers lose their friction coefficient. One thing Chris even mentioned before is that it would be difficult to put a solid number on it as there are so many variables to take into account, such as are we talking about a static load (constant applied force) or a shock load (WOT changes/kick-downs)?

I'm sure there would be some mathematical way to determine an average if all things were equal, but the other and most important variable (in my mind at least) is the status of the crank bolt itself. Unless the bolt is verified to be correctly torqued from the factory and a CBC is installed immediately, there's no real telling if the bolts clamping force remained to spec or loosened by any number of degrees. Unless everything is kept at a constant, the scientific method won't guarantee accurate results.

Ultimately it comes down to your acceptance of risk.

[rmanm4]

Originally Posted by MJ6

Which is technically true, the issue is that we have no idea at what load the friction washers lose their friction coefficient. One thing Chris even mentioned before is that it would be difficult to put a solid number on it as there are so many variables to take into account, such as are we talking about a static load (constant applied force) or a shock load (WOT changes/kick-downs)?

I'm sure there would be some mathematical way to determine an average if all things were equal, but the other and most important variable (in my mind at least) is the status of the crank bolt itself. Unless the bolt is verified to be correctly torqued from the factory and a CBC is installed immediately, there's no real telling if the bolts clamping force remained to spec or loosened by any number of degrees. Unless everything is kept at a constant, the scientific method won't guarantee accurate results.

Ultimately it comes down to your acceptance of risk.

shock load is the issue.

Didnt BMW update the friction plates after 2017/2018???
If so, BMW redid the math!

[M 4 FUN]

Originally Posted by kingofqueenz788

i work as a windshield installer and i do countless 3 series cars and more then half the windshield motor bolts is not even screwed in im talking about sticking up causing play in the wipers. with seeing a thing like this just not even screwed in makes me think more and more abt my hub. also more power puts a lot of stress on the tiny oem sprockt design. i am going with a fix soon also what one do u guys recommend and have experience with

Can you e4xplain how more power put more load on the sprockets?

[MisterF80M3]

Originally Posted by Nothing

As someone that has owned my '16 M3 since new, I have sat back and tried to let the more courageous owners tune and be the guinea pigs while I sat back and watched.

Originally, I saw a lot of debate about the CBC vs hub replacement and honestly, it felt like most of the guys running any mods have opted for the full hub replacement. Are you seeing this differently? Have you had a lot of experience with the CBC and 500-600hp cars? I'd love to go to a Stage 2 tune and maybe play around with the ethanol options that the latest BM3 update has given to us. But even then a Stage 2 car on E30 is hovering just under 600 whp. I also track this car once or twice a year and need that peace of mind.

Thanks for your input.

Stage 2 E30 is nowhere near 600WHP. 600WHP is achieved with a custom E85 tune putting out max stock turbo boost. E30 is ~530WHP.

Do your own due diligence. I wouldn't trust anyone except the data and research that has been provided by other members. There is quite a bit of us with just a CBC on custom e85 tune with no issues. I am coming up on 10k miles with e85 tune and I did close to 100 street tune pulls.

Giant thread regarding this:

https://f80.bimmerpost.com/forums/sh....php?t=1597456

[TopJimmy]

I agree with the WHP levels given by MisterF80M3 for E30 and E85 on stock turbos.

The advice from Chris@VTT is spot on. I knew I would eventually do a custom Paul E85 tune and big turbos, so I did the Fix+CBC from the start. If I had planned to stop at Stage 2 OTS then I should have added just the CBC and beaten up the car BEFORE tuning, so warranty could cover me.

[b16civic]

There are two types they sell

VTT-S55-CBC
And the other one is

VTT-CRANKGAURD-2

Which one is it?

[hellokitty]

Originally Posted by b16civic

There are two types they sell

VTT-S55-CBC
And the other one is

VTT-CRANKGAURD-2

Which one is it?

The first one (CBC).

[M2_MEDUSA]

I've owned the car for 5.500 miles and get on it constantly and go WOT a lot. However one thing I will note is I've never used kick down once. I only drop gears manually. And I drop a gear let it settle for 3-4 seconds and drop 1 more if I need to. If I'm going WOT I'll let the gear settle for those few seconds before I rip it. I'm a huge believer that spun hubs are more rpm dependent than anything else. The faster rpms change the more shock load on the hub. Hence why kick downs have garnished a bad rap in the world of s55. I also never push it past 7k rpm. Car seems stagnant after that anyway so I don't see the point. Nothing is proven and can't really predict the cause of the problem but I just do what makes me feel better and gives me peace of mind.

[overlook637]

Originally Posted by rmanm4

Sprockets have friction plates between them so if your engine has over 600-650 torque it will overcome the friction between the sprockets. It wont matter if the bolt holds with a CBC, the friction plate can be overpowered to slip timing!

It isn't the same as a transmission clutch.

Engine - Clutch- transmission - tires
Engine - friction plates- sprocket - rotating lubricated overhead cams.

[JipperII]

Do I need to do this if I'm just running catted dps, El mid pipe and a stage 2 tune? 2019 comp with 31k miles