Dr Vanos Cryo hub or Beisan?

[jet_dogg]

I don't like monkeying around modifying original factory parts in an irreversible fashion. The issue is with the tabs so I'd rather not alter another part it mates to in order to make it work simply due to cost reasons.

Cryo treated factory hub is laughable as well. I'd never pay a grand for that shit.

[sapote]

I don't like monkeying around modifying original factory parts in an irreversible fashion. The issue is with the tabs so I'd rather not alter another part it mates to in order to make it work simply due to cost reasons.

Cryo treated factory hub is laughable as well. I'd never pay a grand for that shit.

What if the original parts were designed with too much backlash and causing vibration, leading to broken hub tabs? This seems very obvious and so I didn't hesitate to drill the pump disk with 2 new smaller holes to fix the problem and keeping the stock hub. The stock S54 hub and pump disk design is similar to the early E36 S50 design, so the parts have been tested on many engines with seccess. The only issue on the S54 is the disk holes a little too large which cause the broken hub tabs problem.

Again, the issue is not the hub tabs, but the excessive backlash. Of course this can be fixed by using aftermarket hub with wider tabs to reduce backlash with factory disk, or keep the factory hub tabs but drill new smaller holes on the disk. For me it's not just the cost alone, but what if the source for that aftermarket wider tab hub is NLA? Al least there are more stock hubs on this planet than the aftermarket hubs.

[Obioban]

I don't like monkeying around modifying original factory parts in an irreversible fashion. The issue is with the tabs so I'd rather not alter another part it mates to in order to make it work simply due to cost reasons.

Cryo treated factory hub is laughable as well. I'd never pay a grand for that shit.

The issue is pretty well proven to not be with the tabs-- it's with the slop between the tabs and disk.

VAC hub is more likely to have an issue, heavier, and >4x more expensive. And, it's a VAC product. I agree the cryo hub serves no purpose, but I'd happily pay a grand for that before putting a VAC product in my engine.

Paying more for a worse result doesn't sound like a winning strategy to me.

[jet_dogg]

The issue is pretty well proven to not be with the tabs-- it's with the slop between the tabs and disk.

I'm well aware.

VAC hub is more likely to have an issue.

This is pure speculation.

Paying more for a worse result doesn't sound like a winning strategy to me.

My originally posted feelings still stand. I will decide what to do once the vanos is opened up, thanks for your input.

[Obioban]

It’s not really pure speculation— I’m local to VAC, so I see VAC caused engine failures at least monthly. That place is an unbelievable shit show.

[sharadn]

I appreciate all the replies and am waiting for a quote from my trusted mechanic

[Lavatoad]

Checking the tabs tells you nothing other than that the tabs have not yet failed. I've only ever seen one example posted of a partially failed tab, so overall failure must be happening VERY quickly-- which makes the odds of you catching the failure mid way through (by "checking" them) very unlikely.

Once the tab fails, if you're lucky you just have to replace the pump disk (with no core) and exhaust hub ($)... and if you're unlucky you need a new engine ($$$).

Just to add a data point, I caught one of my exhaust tabs partially cracked. It was VERY hard to see with visual inspection while everything was still assembled. Just a small darker line where the tab meets the body do the hub.

Ended up replacing the hub, full beisan kit, cam bolts and chain guides. My old hub makes for a fun desk ornament.

Sent from my LM-V600 using Tapatalk

[heinzboehmer]

Just to add a data point, I caught one of my exhaust tabs partially cracked. It was VERY hard to see with visual inspection while everything was still assembled. Just a small darker line where the tab meets the body do the hub.

Ended up replacing the hub, full beisan kit, cam bolts and chain guides. My old hub makes for a fun desk ornament.

Sent from my LM-V600 using Tapatalk

Oh cool. Pics?

[terra]

Just to add a data point, I caught one of my exhaust tabs partially cracked. It was VERY hard to see with visual inspection while everything was still assembled. Just a small darker line where the tab meets the body do the hub.

Ended up replacing the hub, full beisan kit, cam bolts and chain guides. My old hub makes for a fun desk ornament.

Sent from my LM-V600 using Tapatalk

I had one like this as well (might be the one example Obioban was referring to). Who knows how long it would have lasted like that. I ended up going with the turbotoy hub. That was actually the second time a vanos hub was replaced on my car. The previous owner had one replaced at about 60k miles.

[tcp]

Oh cool. Pics?

I know the question wasn't direct at me, but...

Here's my hub at 120k miles. I got the car at 113k and have no idea how long it was missing a tab. Luckily, it fell into the oil pan.



I replaced it with the Beisan hub.

[bigjae46]

I had my disc done by a machine shop. They mic'd the exhaust hub tabs and milled the holes for a slight interference fit. Didn't make the install any harder.

[sapote]

Here's my hub at 120k miles. I got the car at 113k and have no idea how long it was missing a tab. Luckily, it fell into the oil pan.



I replaced it with the Beisan hub.

You might want to measure the vanos oil pressure just to check, as a one-tab driven disk would have a large force pulling it off center to the shaft, and this could wear out both parts enough to cause lower oil pressure.

[sapote]

I had my disc done by a machine shop. They mic'd the exhaust hub tabs and milled the holes for a slight interference fit. Didn't make the install any harder.

Interference fit between tabs and disk holes? Wow. I think they should have some clearance because the hub is bolted to the sprocket, and the disk is on the vanos, and so they might be a little off center due to tolerance stacking.

[Lavatoad]

I'll get pics this afternoon. May need to get creative with camera and wetting the surface to see the crack. Hard to spot dry.

Sent from my LM-V600 using Tapatalk

[Lavatoad]

Photos of my hub. I marked the end of the crack in the closeup. It had worked it's way roughly 60% across. Consider myself pretty lucky