Best N54 Billet Aluminum Oil Filter Housing Cap?

Which would you have?


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    59

matreyia

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Apr 19, 2017
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It's useless, I had the CTS and it started changing color a month after it was installed and how the "cage" attached to it was half assed so I just installed a new stock unit.

Exactly. Loosey goosey center cage.
 

fmorelli

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BMS without a doubt.
It's useless, I had the CTS and it started changing color a month after it was installed and how the "cage" attached to it was half assed so I just installed a new stock unit.
My CTS unit looks just fine. That said, the cage installation is not the best though it seems to work - half-assed is a fair assessment.

@Payam@BMS, does the BMS locks positively grasp the cage like the factory cap?

I think part of the issue in the CTS design is that the aluminum teeth are rigid (unlike the more flexible plastic cap) so the teeth spacing/design struggles a bit more to have a circular cage flex inward on the teeth. Wonder if it should have been designed with the teeth inside the cage versus outside ...

Filippo
 

The Convert

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Jun 4, 2017
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I'm not sure why you keep hating on my posts lately...
They’re just blatantly biased towards BMS...just as Tony or Chris would be to VTT. My personal opinion is that vendors not post their “opinion” when the community is asked what it thinks of products. Obviously a vendor will promote its product. It just becomes fod in the thread.
 
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Payam@BMS

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Oct 27, 2016
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My CTS unit looks just fine. That said, the cage installation is not the best though it seems to work - half-assed is a fair assessment.

@Payam@BMS, does the BMS locks positively grasp the cage like the factory cap?

I think part of the issue in the CTS design is that the aluminum teeth are rigid (unlike the more flexible plastic cap) so the teeth spacing/design struggles a bit more to have a circular cage flex inward on the teeth. Wonder if it should have been designed with the teeth inside the cage versus outside ...

Filippo

We did the exact thing as stock cap has. Should be same fit.
I haven't really looked too closely at it though.
 

Payam@BMS

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Oct 27, 2016
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They’re just blatantly biased towards BMS...just as Tony or Chris would be to VTT. My personal opinion is that vendors not post their “opinion” when the community is asked what it thinks of products. Obviously a vendor will promote its product. It just becomes fod in the thread.

I guess I think our products are really good? :)
 
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typedRew

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Feb 25, 2019
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We did the exact thing as stock cap has. Should be same fit.
I haven't really looked too closely at it though.
Do you not use one on your car? Seems like you’d have more hands on experience.
 

fmorelli

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We did the exact thing as stock cap has. Should be same fit.
I haven't really looked too closely at it though.
I'd be surprised if the tab is exact as stock, that worked well (but certainly possible). The CTS has the issue. You can't go to a fundamentally stiffer material and have the tab design the same as flexible plastic. Anyone here use the BMS cap, looked closely at its connection, and can provide some specific feedback? The CTS one is loose, I suspect because they couldn't get the flex in the tabs that the plastic has, so the cage slides over but is loose on the tabs. @matreyia looked over the CTS pretty closely; not sure if he ever checked out the BMS unit.

Filippo
 

Jeffman

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Jan 7, 2017
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Good video by @matreyia. I also have the CTS and the stainless steel filter. Now I’m thinking that there’s a good chance the oil is not being properly filtered because there is not a good seal between the CTS housing and the top of the stainless steel filter. So this will allow some oil to leak between the top inside surface of the CTS housing and the top of the metal filter, thereby bypassing the filter media.
I think I’m also going back to at least the stock filter since it has that pliable rubber material to make a seal. Maybe go back to the stock oil cap as well.
 

N54rsenal

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Dec 11, 2018
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So I figured it out wasn't hard, the oil filter cage has a spring loaded oil bypass valve in the very center which can be pushed inwards under high oil pressure in conditions where the filter is clogged or the oil is too thick in winter and the engine demands more oil flow. The plastic circle piece that's surrounding the bypass valve has securing tabs which can break over time and become brittle by many heat cycles. If this happens the plastic circle will fail to seal the oil filter from proper filtration and allow oil to run over the top of the filter making oil filtration ineffective and screw up proper oil pressure and both could lead to severe engine damage.

I would not want to run a oil filter housing cover which does not have the necessary supporting tabs/posts/protrusions to secure the plastic circle with fragile/brittle tabs for the oil by pass valve. It could break at any time during your oil change interval and by then the damage is done!

I would say in the following this is best to worst.
1. ECS - Lowest profile, nice hex head design, secures oil bypass valve
2. STOCK - Secures oil bypass valve and won't burn you badly
3. BMS - Fits oil filter cage nicely and looks really good imo, does not secure oil bypass valve!
4. CTS - It might cool but looks bland imo the cage doesn't lock and it does not secure oil bypass valve!
 
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martymil

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With the CTS cap all you have to do is bend out the little tabs ever so slightly and the cage locks in properly, the three little posts on thr oem cap do
support the cage a little better but never seen it break so I think this would be a personal choice. It would have been good if they implemented it for extra support.

The ECS does have support but they are huge and would cause extra restriction in oil flow if the bypass valve had to operate and It doesn't
have the little bump in the centre either but its flat.

The ecs, bms and cts allow the bypass valve to open a little more when the filter is either dirty or blocked so the engine doesn't starve of oil
if its a good or a bad thing is debatable but its would only operate under extreme conditions where the motor has failed or the filter hasn't been changed
or has failed and the cap would be the least of your problems.

I do my filter and oil changes every 3.5k miles because filters and oil is cheaper than an engine rebuild, labour, hassle and inconvenience of getting a hire car
or buying another vehicle.

Using any of the brands is no real issue as I personally use the CTS one on my built engine and the most powerful bottom mount RHD single turbo in OZ
and the OEM valve cages haven't failed yet.

All the metal replacement have the pro's and cons and if your really get anal about it about the cap failing just change the oem one every 30k miles and you will
keep the full safety net BMW has implemented.
 
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martymil

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If you are really anal about the valve why not change it every so often and keep your good looking cap as the valves are cheap.

 

N54rsenal

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Dec 11, 2018
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Yes you can buy stock replacement oil filter housing caps to swap bypass valves and run any of them as long as you keep a eye on it and change it every so often as preventative maintenance. Why create new problems when we do upgrades to prevent them.

The ECS Tuning cap might still have the oil seeping issue.

If BMS and CTS made a revision on them then this would not be a problem for anyone.
 
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fmorelli

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@matreyia did you take any of the other caps for a spin? Just curious since I know you put the CTS through its paces.

Filippo
 

typedRew

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Feb 25, 2019
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I'm at least happy this was posted, I learned my car is broken and I need a new oil filter cap/cage thing and ordered it right away.
 

Payam@BMS

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Oct 27, 2016
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It’s just disengenuine. It’s like trying to hock product when someone is just looking for opinions from people that have spent their money. Make sense?

I totally understand, maybe you forgot that I wasn't always working for BMS? I just hit my 3 year mark here, you remember VM and my turbo kits?
I bought lots of things for my car, at least 60k in it. I'm sure you can relate. I guess the @BMS behind my name changes things.


Do you not use one on your car? Seems like you’d have more hands on experience.

I actually do not have one on my car, we have them on both of our 135 and 335i.
Every time I put one aside for myself we get a back order and I have to send it out :(


So I figured it out wasn't hard, the oil filter cage has a spring loaded oil bypass valve in the very center which can be pushed inwards under high oil pressure in conditions where the filter is clogged or the oil is too thick in winter and the engine demands more oil flow. The plastic circle piece that's surrounding the bypass valve has securing tabs which can break over time and become brittle by many heat cycles. If this happens the plastic circle will fail to seal the oil filter from proper filtration and allow oil to run over the top of the filter making oil filtration ineffective and screw up proper oil pressure and both could lead to severe engine damage.

At that point, you might want to do earlier oil changes, IMO. I don't think I have seen that happen and I've seen an N54 that hasn't had an oil change in 20k miles.
We'll look more into it though, no reason why we can't incorporate those tabs if it makes it safer :)