Exhaust Hub upgrade

[beta]

So I was reading the very informative exhaust hub post, and also the scarier exhaust hub failure with pictures thread.

Got me thinking that, as a long term project (6-12mo), we should think about making upgraded exhaust hubs.

A CNC upgrade would probably be very expensive because of the intricacy of the helical gears.

Which leaves the approach of buying a new one from bmw and upgrading it as in the first thread linked above. Would cost about 800 for the gears (you have to buy the set) + labor and material to upgrade the part. We could of course do a GB with the M3 guys which should be a largish run and get the cost down.

So for a budget of 1k or less, what's the best way to strengthen or remake the exhaust hub?

[inTgr8r]

Ive thought about this one many times.
...not sure at this point, but definitely on the radar

[Caddyshk]

To be honest; I've driven the hell out of this thing on the street and track; bouncing off the rev limiter at the track every lap on the Andretti straight at Mosport a couple of hundred times and the back stretch at Shannonville. It has 27,000 miles on it. If something was going to let go I suspect it would have happened by now. If it does, oh well...

[Shipkiller]

There is someone making a much stronger exhaust hub for about $450. It is on one of the boards.

[Shipkiller]

Here is the original thread. There are more.
He even has a facebook page for this.

http://www.bimmerfest.com/forums/sho...d.php?t=595394

[beta]

Originally Posted by Shipkiller

Here is the original thread. There are more.
He even has a facebook page for this.

http://www.bimmerfest.com/forums/sho...d.php?t=595394

Good call.

Found the first thread.

Then the very long second thread, where he comes out with V2 and V3.

V3 is a clever solution where he CNCs a ring with the tabs, then welds that to an exhisting hub so you don't have to deal with the complicated splines, and still get very solid tabs.

[bignosejim]

I think that Turbotoy's exhaust hub would be the route I'd take if mine ever fails (maybe before it fails). But I'm still a long way off from thinking about it. His design has no room for the tabs to fall into the timing chain area which is it's best feature. Much cheaper to pay for a new hub than a new engine.

[XMetal]

I like the innovation, but not sure I can convince myself to try it even when the time comes for getting a new hub. The engineer inside me wants test data on the hub and currently, there isn't. I'm sure the OE manufacturer or at least BMW had put millions of miles of testing on their engines and you still see failures. There is virtually no testing done on this this new hub at all other than a few guys running on their cars for a few thousand miles. I'm sorry, but this isn't enough data to convinced me to try it. I would rather take my chances on an OE hub at this point.

[v3.2mc]

^ +1

60k+ on my ///m and zero issues.
all vanos bolts were replaced at inspII, and personally seeing the OE hub tabs... they looked mint... not even any dents from the gear "holes".

[mfanatic325]

Weren't there cryo-treated OEM exhaust hubs over at Dr. Vanos? Or was that something else...

[beta]

Originally Posted by mfanatic325

Weren't there cryo-treated OEM exhaust hubs over at Dr. Vanos? Or was that something else...

I'm not convinced cryo treating is a solution, just a bandaid.

And please stop posting "I have no problems". The truth is 99% of us will never have a problem (I don't have a problem either). The entire forum minus a handful of individuals can post that they've never had a problem, it is well established this is a small percentage of failure.

Some of us like to bullet proof things so they never do fail. I'm in that category. Plus I'd like to get all the tools and do the work myself. If I'm going to keep this car a long time, I really should know the ins and outs of it.

Based on the available data of the failures, as well as the way his V1 failed*, this seems like a reasonable solution. The expected cause of failure seems reasonable as well (cycle wear).

The threads are very long, but if you want more info there's lots of it in there.

To me this is a solved problem, as the solution for the V3 seems like the best of what I threw around with some buddies of mine that are mechanical engineers (barring the ridiculously expensive solutions). And he addressed the weight and balancing concerns.

* his V1 failed with broken tabs. His welds held up perfectly. So in V3 he did thicker tabs (less play), rounded them for better contact, and made the tabs and rings out of one solid piece of much stronger metal.

[Shipkiller]

Beta, I agree with everything you just said. Let me add one more thing.

This 'newer' approach also minimizes or eliminates the 'destroyed engine' scenario cause by the OEM tab egressing from the drive hole, chewing up the sprocket teeth/chain and or making it's way down to the oil pan causing MORE destruction.

While the first iteration of the fix did break, the design kept the sheared tab in the hole. Now, with more trial and error, he came up with a third generation part that appears to be much better than the first generation one.

This is a win-win situation.

[inTgr8r]

Any idea what he's charging for these?

[beta]

Originally Posted by inTgr8r

Any idea what he's charging for these?

Don't want to be specific, but less than a new one (with deposit), and you can ship yours to him to get your deposit back.

So I figured and I'd hijack my own thread, to turn it into a how to do this. I'm considering sending him a new one instead of a used one, not sure it's worth the money or not.

Parts list:

1x Exhaust Hub 11367832031
12x interior vanos hub bolts 07129905536
1x vanos gasket 11367831938
2x banjo bolts 07119905175
4x banjo washers 07119963072

Parts shared with valve adjustment:

1x Valve Cover Gasket 11127832034
6x Spark Plug Hole Gasket 11127831271
2x Valve Cover Seal Washer Grommet 11121437395
13x Valve Cover Nut Grommet 11127830972
2x PCV Return Line Gasket 07119963129

Tools:

11 9 130 / 83300493749 - Cam Timing Tool
11 7 342 / 83300491086 - Extra Cam Locking Pin
11 2 300 / 83300490861 - Flywheel Locking Pin

Optional tools:
11 7 160 / 83300493805 - Vanos Adj of Spline Hub handle
11 5 100 / 83300491056 - Crank turning fixture

DIY links:

SYT Shadow DIY

Hutch 430 Part 1
Part 2
Part 3
Part 4
Part 5

Part numbers for special tools

I need some help with the tools I'll need. I imagine I need a set of small spanners. I'm also going to need a small torque click wrench. I was hoping for split beam (as they don't lose precision, nothing under tension), but they don't seem to make them for small numbers like 10Nm. I like to get the best tools I can afford and pass them down to the kids.

Do I need to jack the car up on the Z4M? or can everything be done from the top?

[Shipkiller]

I bought the timing tool from Tischer last year. It was about $89.00

[inTgr8r]

Thanks for all the numbers Beta.

[mfanatic325]

My buddy Chun was the one that helped me with my valve inspection and exhaust hub/tabs checkup last time. We'll be doing this once every year and a half or so for my car.
I recall that we were able to do everything just from the top of the car, no need to raise the car up at all. The radiator fan was annoying =/

[Finnegan]

Here's Chun's pics and write up on the replacement. Hey also has the timing kit/pieces. Pretty awesome he was able to do this entire job during the night before a track day, and then go and drive.

[bignosejim]

Just remember that our vanos is closer to the front cross member than an e46. You should definitely get some pics of disconnecting the vanos from the helical gears. Looks like it didn't interfere with runnerx though.

[beta]

Originally Posted by mfanatic325

My buddy Chun was the one that helped me with my valve inspection and exhaust hub/tabs checkup last time. We'll be doing this once every year and a half or so for my car.
I recall that we were able to do everything just from the top of the car, no need to raise the car up at all. The radiator fan was annoying =/

Huh. Can I bribe you guys with beer? I'm due for a valve adjustment (already have all the parts for that). Was considering getting the exhaust hub replaced while I was at it.

[inTgr8r]

Originally Posted by bignosejim

Just remember that our vanos is closer to the front cross member than an e46. You should definitely get some pics of disconnecting the vanos from the helical gears. Looks like it didn't interfere with runnerx though.

Looks like he raised the engine though.....

[inTgr8r]

Originally Posted by Shipkiller

I bought the timing tool from Tischer last year. It was about $89.00

MSRP shows as $ 97 with online price $117
WTF?