Hello fellow Bimmerboost members,
A few of you may know me from "the other forum" and it has been some time since I've been on this one here as well. As I'm not much in favour of the policy (the word comes from "police" I guess...) of E90post and more precisely at its way of handling conflicts (mostly by inflicting bans on members who have posted lots of useful information), I have also decided some time ago to join Bimmerboost.
Some of you may know the reviews I've written so far, and I would like to make them available to Bimmerboost as well - together with some new ones and updates to the existing reviews. The present article is therefor one among several threads that I will be posting individually (to make them easier to find without having to wade through many posts in one thread).
Almost all of these are performance oriented, and I will therefor post most of them in the N54 sub-section. @Sticky : If you think one or the other is better placed elsewhere, just move it there please.
But enough of the preamble, here we go.
---
AR Design oil catch can
Why?
Ever since I started modifying my car, I have been concerned with its long-term reliability. Some modifications such as the additional oil cooler or even the upgraded intercooler, while enabling the engine to deliver its power consistently and without heatsoaking, also alleviated the thermal stress on the turbos and therefore contribute to its longevity. However, I learned that more or less all engines suffer from so-called "blow-by" gases which are excess gases that leak from piston rings during the combustion process and get back into the engine crankcase; from there they are vented (by crank case vents) back into the intake system of the engine to be combusted again. That wouldn't be so bad, but the blow-by also contains oil from the crankcase, and this is the real problem - the oil coats the intercooler (thus decreasing its cooling efficiency), the intake valves and other engine components, impacting their performance negatively.
Now, this oil should be caught before it creeps everywhere, and this is commonly done by a so-called oil catch can ("OCC"). Its function is to filter the blow-by gases and to extract the oil from them, retaining the latter in a container that is (ideally) easy to drain.
How?
For quite some time, Riss Racing was more or less the only option for an OCC that was specifically adapted to our
engine. However, from what I've read on this forum, the quality of this product was only very mediocre and it had a tendency to leak all over the place, due to the cheap components used in its construction.
As I had so far had excellent experience with other products from AR Design, I was glad to learn that they were developing an OCC for the N54. At that time, other competitors (such as BSH or BMS) were not on the market yet, and in my opinion the use of a real 5 micron filter instead of just some steel wool for filtering was a superior solution. Therefore I jumped on the group buy that was organized for this OCC. The price is admittedly not very low (list price is 229 USD), but I am happy to pay more for a quality product that fits correctly than throwing some stuff together myself and be finally unhappy because it does not work right. An additional advantage of the OCC from ar design consisted in the fact that they offered the possibility to mount it on the passenger side in the engine bay, which was necessary in my case as due to the STETT cold air intake and charge pipe I did not have enough space for the OCC on the driver's side.
With some delay, the OCC arrived and was excellently packaged in a big cardboard box. Upon unpacking the various items, I was immediately aware of the heavy, confidence-inspiring solidity of the OCC. Also, the mechanism to remove the filter and drain the oil is really easy and obvious. That was clearly no cheap ebay-like item but a thoroughly engineered solution. All mounting brackets for the passenger side location were also provided.
Here's a photo (not mine, I hope the forum member won't mind) of what the components look like once unpacked:
![Click here to enlarge]()
As always, I had the OCC installed at Daum Motorsport and from what they told me it was no problem at all, and they confirmed that all components seem to be of very high quality. It IS a tight fit, and the OCC is quite close to another hose but without actually touching it. However, it does fit into the engine bay, and the mounting brackets provided by ar design had the right size. For additional insight into the installation procedure, I would recommend having a look at
Former_Boosted_IS' DIY of the BSH OCC, as the install is pretty similar.
Once in the engine bay, the OCC blends in very well and if you wouldn't know it, you could think it's an OEM part. It's also easy to access, you can see the reservoir window (i.e. how much oil is in the OCC) and the oil can easily be drained in that position, without having to demount the whole OCC.
Here are two photos of what it looks like after installation:
Photo from the side:
![Click here to enlarge]()
Photo standing in front of the car:
![Click here to enlarge]()
Improvements?
I had the OCC installed for several ten thousand kilometers, and to my disappointment it was apparently not very efficient. After about 8.000km I had it taken out and emptied, and there was not much oil in it at all. I repeated that procedure several times over the next about 35.000km, with a similar result. Considering that I do tend to drive my car quite hard and use it on the Nürburgring, this is rather surprising.
In my opinion, the tubes going to and from the OCC are simply too long. There's a good reason the stock breather valves are so close to the recirculation circuit, and I think that the overly long tubes - which are of course due to the installation spot - are detrimental to its efficiency.
I recently replaced the AR Design OCC with an OCC from BMS (which is installed only a few centimeters away from the stock breathing apparatus), and after only a few thousand kilometers there was already two finger width of oil inside the OCC. I therefor believe that it is much better to have as little way for the crank gases to travel in order to filter them of oil, which the BMS OCC does but not the AR Design one.
Problems / disadvantages?
The main disadvantage is that it appears not to be very efficient, which for the price it is sold at it should really be. The OCC itself is without any doubt very well made, but the spot that was chosen for its installation counters this and leads to its (in my experience) poor efficiency.
Alpina_B3_Lux
A few of you may know me from "the other forum" and it has been some time since I've been on this one here as well. As I'm not much in favour of the policy (the word comes from "police" I guess...) of E90post and more precisely at its way of handling conflicts (mostly by inflicting bans on members who have posted lots of useful information), I have also decided some time ago to join Bimmerboost.
Some of you may know the reviews I've written so far, and I would like to make them available to Bimmerboost as well - together with some new ones and updates to the existing reviews. The present article is therefor one among several threads that I will be posting individually (to make them easier to find without having to wade through many posts in one thread).
Almost all of these are performance oriented, and I will therefor post most of them in the N54 sub-section. @Sticky : If you think one or the other is better placed elsewhere, just move it there please.
But enough of the preamble, here we go.
---
AR Design oil catch can
Why?
Ever since I started modifying my car, I have been concerned with its long-term reliability. Some modifications such as the additional oil cooler or even the upgraded intercooler, while enabling the engine to deliver its power consistently and without heatsoaking, also alleviated the thermal stress on the turbos and therefore contribute to its longevity. However, I learned that more or less all engines suffer from so-called "blow-by" gases which are excess gases that leak from piston rings during the combustion process and get back into the engine crankcase; from there they are vented (by crank case vents) back into the intake system of the engine to be combusted again. That wouldn't be so bad, but the blow-by also contains oil from the crankcase, and this is the real problem - the oil coats the intercooler (thus decreasing its cooling efficiency), the intake valves and other engine components, impacting their performance negatively.
Now, this oil should be caught before it creeps everywhere, and this is commonly done by a so-called oil catch can ("OCC"). Its function is to filter the blow-by gases and to extract the oil from them, retaining the latter in a container that is (ideally) easy to drain.
How?
For quite some time, Riss Racing was more or less the only option for an OCC that was specifically adapted to our
engine. However, from what I've read on this forum, the quality of this product was only very mediocre and it had a tendency to leak all over the place, due to the cheap components used in its construction.
As I had so far had excellent experience with other products from AR Design, I was glad to learn that they were developing an OCC for the N54. At that time, other competitors (such as BSH or BMS) were not on the market yet, and in my opinion the use of a real 5 micron filter instead of just some steel wool for filtering was a superior solution. Therefore I jumped on the group buy that was organized for this OCC. The price is admittedly not very low (list price is 229 USD), but I am happy to pay more for a quality product that fits correctly than throwing some stuff together myself and be finally unhappy because it does not work right. An additional advantage of the OCC from ar design consisted in the fact that they offered the possibility to mount it on the passenger side in the engine bay, which was necessary in my case as due to the STETT cold air intake and charge pipe I did not have enough space for the OCC on the driver's side.
With some delay, the OCC arrived and was excellently packaged in a big cardboard box. Upon unpacking the various items, I was immediately aware of the heavy, confidence-inspiring solidity of the OCC. Also, the mechanism to remove the filter and drain the oil is really easy and obvious. That was clearly no cheap ebay-like item but a thoroughly engineered solution. All mounting brackets for the passenger side location were also provided.
Here's a photo (not mine, I hope the forum member won't mind) of what the components look like once unpacked:
As always, I had the OCC installed at Daum Motorsport and from what they told me it was no problem at all, and they confirmed that all components seem to be of very high quality. It IS a tight fit, and the OCC is quite close to another hose but without actually touching it. However, it does fit into the engine bay, and the mounting brackets provided by ar design had the right size. For additional insight into the installation procedure, I would recommend having a look at
Former_Boosted_IS' DIY of the BSH OCC, as the install is pretty similar.
Once in the engine bay, the OCC blends in very well and if you wouldn't know it, you could think it's an OEM part. It's also easy to access, you can see the reservoir window (i.e. how much oil is in the OCC) and the oil can easily be drained in that position, without having to demount the whole OCC.
Here are two photos of what it looks like after installation:
Photo from the side:
Photo standing in front of the car:
Improvements?
I had the OCC installed for several ten thousand kilometers, and to my disappointment it was apparently not very efficient. After about 8.000km I had it taken out and emptied, and there was not much oil in it at all. I repeated that procedure several times over the next about 35.000km, with a similar result. Considering that I do tend to drive my car quite hard and use it on the Nürburgring, this is rather surprising.
In my opinion, the tubes going to and from the OCC are simply too long. There's a good reason the stock breather valves are so close to the recirculation circuit, and I think that the overly long tubes - which are of course due to the installation spot - are detrimental to its efficiency.
I recently replaced the AR Design OCC with an OCC from BMS (which is installed only a few centimeters away from the stock breathing apparatus), and after only a few thousand kilometers there was already two finger width of oil inside the OCC. I therefor believe that it is much better to have as little way for the crank gases to travel in order to filter them of oil, which the BMS OCC does but not the AR Design one.
Problems / disadvantages?
The main disadvantage is that it appears not to be very efficient, which for the price it is sold at it should really be. The OCC itself is without any doubt very well made, but the spot that was chosen for its installation counters this and leads to its (in my experience) poor efficiency.
Alpina_B3_Lux