OE Replacement Vanos Hub (Spring) Covers

[straightupfunk]

Hey guys,

I've been working on another option for a clip-on replacement for these shitty plastic vanos spring/hub covers. So far, the only option we have (without retiming the vanos system) is the over-engineered stupidly-expensive Slonik billet aluminum covers... I recently finished my rod bearings and started putting some time into making a cheaper alternative. I have it modeled in Solidworks, and my 3D test prints come out and clip on with zero slack, so I think I have the dimensions correct for an OEM replacement.


I also spent some time trying to figure out what material the OEM units were, and it looks like it's like Nylon 6 (or 6/6) from what I can tell. Anybody on here with plastics insight please chime in, as I'm basing this off the standard plastic burn test. You can identify the injection molding ejection pin marks on the back side of the original units, so OEM was definitely some sort of thermoplastic. The black color might indicate a Nylon-polymer blend, maybe with carbon? We just need a thermoplastic with a transition temperature a bit higher than these engine's nominal oil temp (~200F).


My goal is to have a solid model (uploaded to Thingiverse.com for anyone to use/modify for free) and a material identified that at least matches OEM spec. I think with that combination we'll have something that could be printed from a vendor (stratasys/xometry/etc) for way cheaper than the Slonik option, that ideally lasts as long the S65 valve cover gaskets.

[Redd]

Originally Posted by straightupfunk

I think with that combination we'll have something that could be printed from a vendor (stratasys/xometry/etc) for way cheaper than the Slonik option, that ideally lasts as long the S65 valve cover gaskets.

Nice! So the cover is designed to be replaced every time you do your valve covers?

[drwankel]

Why not pursue something made of metal instead? Not sure replacing plastic with plastic is the best approach, considering when it fails it can take the engine out with it.

[MidnightM3]

Just installed the Slon vanos covers when installing new FC valve covers and gaskets, after discovering my OE vanos covers were splitting on both sides. The OE covers are very flimsy and if they fall off alignment, crack and eventully get ground up they can clog up the oil pickup and blow the motor. This has already happened to another owner and was costly. The SLON covers are a great solution and were worth it for longevity and piece of mind (to me).

[MisterClutch888]

Better chime in on the materials that you are going to use, or else the thread will blow up just like on your FB post.

[spammysammich]

I'm sure a cheaper solution would be welcome if materials compatibility and longevity/durability are on point. Considering how BMW missed the mark with their engineering $$$ behind them, I worry that a cost effective aftermarket solution won't be sufficiently engineered to fix the issue we're discovering. Meaning no offense to the skill of the OP, I'm glad somebody is looking into this considering how little BMW gives a crap about something like this. It's like cheap, brittle plastics give their engineers orgasms or something with how often they throw them into applications where they don't belong.

[straightupfunk]

Originally Posted by MisterClutch888

Better chime in on the materials that you are going to use, or else the thread will blow up just like on your FB post.

Yeah, I'm kind of surprised at how many people apparently shy away from replacing OE with OE-equivalent. OEM's run plastic inside the engine all the time... if this part were available from BMW, but known to last as long as spark plugs or valve-cover gaskets, I think the conversation would be different and it would just be another wear-item like air filters or tires.


Right now the only material recommendation's I've gotten are Ultem or PEKK for FDM processes, but those are extremely exotic and the temp ratings for those are like 3x what the engine oil temp gets up to. I'm starting a Nylon/Carbon SLS print tomorrow and will be heat-cycling it in oil on a test-bench setup to see how it holds up. The OE's were injection molded Nylon (likely a 6 or 6/6 blend w/ carbon to give it the black color). I just want an equivalent for cheap. I'm not looking to improve or move to a more exotic/expensive material to increase longevity past the OE part.


So far the only folks with any 3D printing/AM experience would "never run plastic inside their engine" and recommend changing the design to metal. I mean, cool, maybe in the future I'll model something that can be done with a water-jet out of spring steel, but if I'm not looking to improve on OE, and just produce an equivalent (or near equivalent) solution... knowing up front that it might last 4 years max, but cost 1/5th the price is good enough for me. Hopefully the community finds value in this endeavor lol. If not, cool, the design files will be posted online for anyone to download for free.


So far, Xometry is quoting $60/ea for Ultem 1010 (~550F glass transition temp, wayyy overkill), which already comes out to half the Slonik covers. Can probably bring that down with more cut-outs to reduce total volume, but I'm really not convinced Ultem is the only option for something like this to just meet OE spec.

[drwankel]

Originally Posted by straightupfunk

OEM's run plastic inside the engine all the time... if this part were available from BMW, but known to last as long as spark plugs or valve-cover gaskets, I think the conversation would be different and it would just be another wear-item like air filters or tires.

Valvecover gaskets, spark plugs, air filters and tires don't destroy a very expensive engine when they break. This does. That's the reason why you are getting pushback.

There's no way to know when these are going to let go on the drivers side of the engine outside of pulling the valvecovers.

Why do you think people aren't replacing rod bearings with new BMW bearings? Rod bearings aren't supposed to be a maintenance item- and neither are the vanos covers.

[straightupfunk]

Originally Posted by drwankel

Valvecover gaskets, spark plugs, air filters and tires don't destroy a very expensive engine when they break. This does. That's the reason why you are getting pushback.

There's no way to know when these are going to let go on the drivers side of the engine outside of pulling the valvecovers.

Why do you think people aren't replacing rod bearings with new BMW bearings? Rod bearings aren't supposed to be a maintenance item- and neither are the vanos covers.

I found half of one sitting in the bottom of my oil pan when i dropped it to do rod bearings. Inspecting them for cracks when doing valve cover gaskets would indicate if they were brittle/cracked and near breaking.

[Redd]

Problem is the moment u touch them, they will crack, and you better have a replacement on hand.

OP kudos to you for doing this, and even heat cycle testing it. My personal view is that if you make it out of some nylon blend, it is still not a lifetime part. I'm slowly replacing common wear and tear items in my car to lifetime - or at least much longer than stock - parts. This is the reason the Slon VANOS caps appeal to me, despite the price. I can do it once and never have to worry about them again. Likewise, if I wanted something cheaper, I could get four 80mm Ti washers done up for less than the price of one 3D printed cover, and that too would be a lifetime part. That would require re-timing but that's a one time effort/cost.

So I think while the idea of an aftermarket VANOS cap is a great idea, I don't think it will really take off if it needs to be inspected and replaced at every valve cover replacement.

[straightupfunk]

Originally Posted by Redd

Problem is the moment u touch them, they will crack, and you better have a replacement on hand.

OP kudos to you for doing this, and even heat cycle testing it. My personal view is that if you make it out of some nylon blend, it is still not a lifetime part. I'm slowly replacing common wear and tear items in my car to lifetime - or at least much longer than stock - parts. This is the reason the Slon VANOS caps appeal to me, despite the price. I can do it once and never have to worry about them again. Likewise, if I wanted something cheaper, I could get four 80mm Ti washers done up for less than the price of one 3D printed cover, and that too would be a lifetime part. That would require re-timing but that's a one time effort/cost.

So I think while the idea of an aftermarket VANOS cap is a great idea, I don't think it will really take off if it needs to be inspected and replaced at every valve cover replacement.

washers would be a permanent fix if you were going that in-depth, but that's totally different than the OEM clip-on covers. The cool part is I'm not asking for it to take off because I'm not a business trying to sell anything. Apparently that's hard for this community to understand lol... This is a fun learning experience for me, and because of the price of the Slonik option (for what it is), I simply refuse to pay for them. If I end up machining my own covers because the 3D-printing materials really don't hold up, oh well, at least the community will have the design of the part for free.

[straightupfunk]

For reference: https://www.mcmaster.com/8974K97-8974K65/

72" long x 4" round aluminum stock. The Slonik covers are ~3/4" thick, so you get 72 (conservative) sets per $600 six-foot round stock. That gets you 18 sets of covers, that sell for like $400 each. The only reason I can see people tolerating a vendor purchasing $600 in materials and doing some generic cnc to it, and charging $7000, is because there is no other clip-on option.

[Helmsman]

Originally Posted by straightupfunk

For reference: https://www.mcmaster.com/8974K97-8974K65/

72" long x 4" round aluminum stock. The Slonik covers are ~3/4" thick, so you get 72 (conservative) sets per $600 six-foot round stock. That gets you 18 sets of covers, that sell for like $400 each. The only reason I can see people tolerating a vendor purchasing $600 in materials and doing some generic cnc to it, and charging $7000, is because there is no other clip-on option.

Kudos for developing this!

Seen people react to Slonik cost, which like you indicate most probably harvest a massiv profit margin. Still a pretty good deal vs blown engine or BMWs alternative - great opportunity for both parties...😉.

Went recently Slonik myself. I'm sure plenty people will go for a lower cost alternative once its available.

Ps. Believe Slonik is using 2024-T6 aluminium, as far as I understand pretty stout material for demanding applications. No idea what it cost.

[serranot]

I have zero entrepreneurial sense, so I appreciate Slonik and this guy doing what they do. And BE. and a load of other folks here. They do what I can't or won't. I tip my hat to you folks.

[Redd]

Just remembered that Mr. VANOS UK attempted to do 3D printed S65 VANOS caps but the project seems to have died a natural death. Not sure what happened.

[straightupfunk]

Originally Posted by Helmsman

Kudos for developing this!

Seen people react to Slonik cost, which like you indicate most probably harvest a massiv profit margin. Still a pretty good deal vs blown engine or BMWs alternative - great opportunity for both parties...😉.

Went recently Slonik myself. I'm sure plenty people will go for a lower cost alternative once its available.

Ps. Believe Slonik is using 2024-T6 aluminium, as far as I understand pretty stout material for demanding applications. No idea what it cost.

McMaster has 2024 4" round stock at 6' length for $950, so it's about 50% more expensive if that's actually what they're using. Also McMaster is just for US pricing, and not for any bulk deals.

[straightupfunk]

Originally Posted by Redd

Just remembered that Mr. VANOS UK attempted to do 3D printed S65 VANOS caps but the project seems to have died a natural death. Not sure what happened.

Thank you! I knew someone had to have attempted this. Interesting that he went with metal and ended up kept the whole plastic design... you would think the nylon design worked because of the material's flexibility. Not sure how that solid ring would expand around the lip of the vanos assembly. I'm gonna reach out to him. I would think if you went with metal you'd end up with something similar to Slonik.

[Redd]

I think someone on here bought the remaining pieces off Mr. VANOS. Maybe it was @helmsman.

[Helmsman]

Originally Posted by Redd

I think someone on here bought the remaining pieces off Mr. VANOS. Maybe it was @helmsman.

Memory like an elephant, yessir I tried. After order turned out they didn't have any left nor wanted to produce any. Shipped me 2pc used OEMs for £120. Now that is good margin business. Anyone interested, anyone?

[Drifter2090]

Glad people are working on a cheaper replacement, the slonik units are very high quality and work well but 600usd seems quite steep

[Supra2k6]

Subbed and looking forward to updates. Would to do this at the same time as VC in a month or two.

[Melbourn3]

When my father looked at the Slon Vanos covers he said these are very well made and made from a single block of metal. I'm not too sure if I would be willing to switch them out every VC change or if the plastic its going to be made of would have the same problems as the OE ones.