[F87source]

Credit: Filterwears https://filterwears.com/products/fil...10380516589615


Introduction:

In this product review I will be doing an in depth analysis of the Filterwears Intake Pre-Filter, and why I think anyone with an aftermarket cone filter should have one of these on their intakes. The specific Filterwears Pre-Filter that I will be looking at in my review is sized to approximately fit my Turner Motorsport Carbon Fiber intake for the BMW F series n55 engine (but it actually fits absolutely perfectly, so I would suspect the filter dimensions listed on Turner Motorsports website is a bit off), but the details that I talk about in this review should apply for all of the Pre-Filters that Filterwears manufacturers.


If you want to buy a Pre-Filter for your cold air intake here’s a link to the Filterwear’s website where you can use their excellent fitment tool to find a Pre-Filter suitable for your intake: https://filterwears.com/


If you want to buy a Pre-Filter for your Turner Motorsport carbon fiber N55 intake here’s a link to buy the same Pre-Filter I have: https://filterwears.com/products/fil...10380516589615


Discount Code: The Filterwears team was also kind enough to provide all the readers here on bimmerpost with a discount code for 10% off any purchase on their website. The code is: bimmerpost10.

Note: I do not make a single penny if you use this discount code, this was just a courtesy provided by Filterwears to the readers on bimmerpost and that is it.



Disclaimer:

Damage/Injury Disclaimer: Any information, guidance, technical advice, coding advice, tuning advice, datalogging advice, installation instruction, calculation, experiment, safety information, or product installation demonstrated in my reviews is to be consumed and or done at your own risk. I will not be responsible for personal injuries, injuries to others or any living being, or any damage to your car, or any property damage.

Monetary disclaimer: I do not make commission, or profits or any kind of monetary gain from the sale of the Filterwears Intake Pre-Filter.

Sponsorship disclaimer: The way my reviews work is that I determine what product that I want to buy and actually use on my own car, and during this process the product that I end up choosing is what I believe is the best option on the market. I then reach out to the company offering the product and ask them if they would be willing to sponsor me in a review, if the answer is yes then I write a review, if the answer is no I would end up buying the product (sometimes at a later date) but I wouldn’t complete a detailed review about it (I might write something, but not to the same extent as my standard reviews). But the critical thing is that I reach out for a sponsorship and not the other way around, this means that the products I am reviewing are actually things I believe in and would use on my own car. This also means that I am not being paid to review something I do not care about. Would I do a review if a sponsor reached out to me? The answer would depend on if I believed in the product, and I would make it clear in my review if this were the case. But at the time of writing this review, such an interaction has not occurred yet.


Time of writing disclaimer: everything I am writing about in this review is described at the time of writing and may not be updated in the future, so there is a potential that things are no longer accurate in my comparisons as parts are changed and upgraded as time passes.


Bias and comparison disclaimer: Throughout this review I will attempt to be as unbiased as possible while drawing comparisons to other products.


Mistakes and Inaccuracies Disclaimer: Throughout my review I will try to be as factually accurate as possible, but there are always chances that I make mistakes and write things that are incorrect/false. If this is the case please point it out to me and if indeed it is true that I am incorrect, I will correct these mistakes and apologize for them. Afterall I am only human, so mistakes can and will inevitably happen.


Subjective Disclaimer: Please note, these reviews are also written in my own opinion, so when I am comparing different products to determine what I see as the best, there are many factors that I go through to form this opinion. Obviously there will be disagreements between people, so I will do my best to objectively determine what I deem to be the best, but at the end of the day it is still just my own opinion whether it be right or wrong. Take whatever I say in my reviews with a grain of salt.


Information Disclaimer: I read a lot of material over the years just out of sheer interest or to make these reviews. I also accumulated a lot of knowledge over my many years of education that are really relevant to cars (Physics, Chemistry, and Mathematics). That being said, my reviews are mostly based on this accumulated knowledge and I cannot always cite these sources due to the original source material possibly being lost to time, or there being so much knowledge compiled to make a single point. So, when possible I will cite my source(s) (for example data on tensile strength of a metal, or peer reviewed research). There are cases when I get information from blog posts, youtube videos, or forum posts I may not cite it, because I go through a lot of these sources only to use the gained knowledge in a small section of my review and it is not feasible to list them all. So pretty much what I am trying to say is I am not citing “common knowledge” - I will cite peer reviewed research and photos though (if applicable or used), or really explicit user experiences (if applicable or used).



Image Credits:

Images and videos used in this review are all property of their rightful owners as credited below each image, I am just using them for the purpose of this review but if you (the owner of the image) would like them removed please let me know via pm. Otherwise thanks to the respective image owners (I made sure to credit your online name and link where I found the photo) of the photos, without you this review would be so much more bland.



Review Disclaimer:

First and foremost I would like to thank Alan from Filterwears for agreeing to sponsor me for this review. Despite this I will remain as unbiased as possible during the review. Please note, the dynamics of this relationship was that I reached out for a sponsorship review and not the other way around. This should demonstrate how I truly feel about Filterwears Intake Pre-Filter - in the sense that I truly believe it is an absolute essential for anyone running an aftermarket intake with a cone style filter. In fact I actually have this Pre-Filter installed on my own m2 (with my Turner Motorsport carbon fiber N55 intake) as of now, and I really appreciate the additional protection that it provides my engine.



Discount Code: Once again the Filterwears team was also kind enough to provide all the readers here on bimmerpost with a discount code for 10% off any purchase on their website. The code is: bimmerpost10.

Note: I do not make a single penny if you use this discount code, this was just a courtesy provided by Filterwears to the readers on bimmerpost and that is it.



What is an Intake Pre-Filter?:

Let’s begin this review by answering the questions, what is an intake pre-filter? Well like the name suggests, an intake pre-filter is a filter that goes before the intake. So in the context of a Filterwears pre-filter, it is a mesh-like sock that goes over and covers the cone filter on your intake. This pre-filter then protects your intake filter from various things - which we will discuss next.



Filter-Wears Intake Pre-Filter:

Now lets go over the Pre-Filter featured in this review, and that is the Filterwears intake Pre-Filter. This particular pre-filter will be analyzed in depth in the upcoming sections.



Unboxing and Overview:

Let’s first go over the unboxing of the Filter-Wears intake Pre-Filter, and here are the images:


Credit: F87Source


Credit: F87Source


As you can see from the images, the Filter-Wears intake Pre-filter is packaged very simply. It comes folded up in a clear plastic bag with a cardboard label stapled over it to keep the bag shut. It also comes with a second Filter-Wears sticker in the bag.


Credit: F87Source


Credit: F87Source


Credit: F87Source


Next we have images of the pre-filter taken out of the bag and unfolded. The pre-filter has a very smooth mesh like feel to it and does not leave behind a residue or coating that can be wiped off (for anyone that was asking me before) - so the hydrophobic treatment applied to these pre-filters do not leave behind any kind of residue or stickiness. This is a good thing because it means your filter will not be contaminated by any sort of coatings. The pre-filter also has an elastic around the bottom that will hug onto your intake filter and it has 4 pull tabs that allow you to easily remove the pre-filter when it is snug against your intake filter.


Overall packaging was fine, and the product looks absolutely excellent thus far - no complaints from me.



Customer Service:

Next I would like to discuss customer service that I experienced with Filter-Wears.

Customer service with Filter-Wears has been nothing short of excellent. The customer support team replied promptly to answer all of my questions, and were always willing to help me. For instance I had a small address issue on my shipment (I was shipping to a Canada Post Flex Delivery “PO BOX” so the address fields are a lot longer than normal addresses so autofill generators have difficulty with this) and my delivery address was missing a field. So I reached out to the Filter-Wears team and they spent quite a bit of time trying to help with USPS and also walking me through what I had to do to get this issue corrected, and they assured me that no matter what they would take care of me. The end result was my shipment arrived safe and sound after I reached out to Canada post. So overall my experience with the customer service of Filter-Wears was great - nothing to complain about.



Shipping:

Next I would like to talk about shipping, like I alluded to in the customer service section there was a small issue with my shipment because the delivery address was missing a field. Despite this shipping was quick, the order was processed by the Filter-Wears team and with USPS within a day or so, and it arrived in Canada within ~2 weeks. So on the shipping front everything was great and I have no complaints about this as well.



Specifications and Functionality:

Next let’s go over the specifications and functionality of the Filterwears Pre-Filter:

1) Water Repellent:


Credit: Filter-Wears https://filterwears.com/

The Filterwears Pre-Filters are water repellent due to a special hydrophobic treatment applied to the Pre-Filter during the manufacturing process. This special coating allows the Pre-Filter to be water repellent without clogging any of the micro openings on the Pre-Filter, and this is why you do not want to spray any aftermarket water repellent coatings onto these Pre-Filters. But the key point here is that splashes of water onto your intake filter will be repelled by the Pre-Filter and not result in engine hydrolocking - and this is important for BMW owners with hood venting (GTS style hoods for instance, or anything even more aggressive) or with intakes relocated behind the front kidney grilles.

2) Additional Filtration: The Filterwears Pre-Filters provides additional particle filtration, and can filter out particles larger than 0.005” or 0.127 mm. For reference a grain of sand is classified to be anywhere from 0.06 mm to 2.0 mm, this means a vast majority of what is considered to be sand can be filtered out by the Filterwears Pre-Filter.

3) Extend Filter Service Interval and Service Life: The Filterwears Pre-Filters should extend the service interval for an intake filter because of the additional filtration it provides - meaning you can drive longer before having to clean your filter. This Pre-Filter should also extend the service life for intake filters as well because if your filter is exposed to less debris and has to be cleaned less, it will not wear out as fast and should last longer.

4) Durable and added Protection: Filterwears Pre-Filters are advertised to be extremely resistant to puncture, and this is very important because the intake filters they go on can be located anywhere - for example behind the front kidney grilles. This means these Pre-Filters will be subjected to regular rock and debris impacts, and thus they must be durable enough to withstand this abuse without failing. As a result they will also add protection to the intake filter, because the Pre-Filter is taking the impacts instead of the filter.

5) Function in any kind of conditions: The Filterwears Pre-Filter are rated to be able to withstand up to 450 degrees Fahrenheit (or 232 degrees Celsius), and will have no reduction of functionality in freezing temperatures. So this means it should be able to function in any kind of operating conditions your intake filter will ever see- from the extreme heat of an engine bay or freezing cold winter days.

6) Large Size and Shape Selection:


Credit: Filter-Wears https://filterwears.com/

The Filterwears Pre-Filters come in a vast number of sizes and shapes, so you will always be able to find a Pre-Filter for any intake filter you may have. This is especially important for intakes like the Turner Motorsport Carbon Fiber Intake for the BMW F series N55, as this intake had a very unique wide and short filter design that has no direct replacements on the market.

7) Cheap: Filterwears Pre-Filters are relatively cheap, so they can be easily replaced when they eventually wear out - the hydrophobic coatings on pretty much any Pre-Filter will eventually wear out over time meaning your Pre-Filter will lose the ability to repel water. So if you require the water repellent ability from your Pre-Filter, then you should regularly replace them every 6,000 - 12,000 miles as per Filterwears. If you do not require the water repellent ability then you are free to keep using your Pre-Filter until it becomes damaged.

8) Customizable: Filterwears Pre-Filters come in red, blue, and black so there is a decent selection of colors to match your engine bay theme, and this is great because most Pre-Filters out there don’t have a good color selection.

9) Low Restriction: Filterwears Pre-Filters only minimally restrict air flow to the intake filter - which is important when you do not want to rob horsepower from your high flow intake. In fact Pre-Filters help maintain your intake filter’s flow rate over a longer period of time, because they block particulates from clogging up your filter. This means the small amount of flow you lose by running a Pre-Filter will be quickly made up by the ability of your filter to remain clean and unclogged, compared to an unprotected filter which rapidly gets dirty.

10) Easy install and removal: Filterwear Pre-Filters have tabs on the bottom that allow you to easily grab the Pre-Filter and stretch it over your intake filter. The Pre-Filter also has an elastic bottom that contracts around the base of your filter sealing it off, so you don’t need to worry about tying the Pre-Filter shut. This all allows for an easy install and removal.


Credit: Filter-Wears https://filterwears.com/



Credit: Filter-Wears https://filterwears.com/



Why is an Intake Pre-Filter a Good Idea?:


So why are Pre-Filters a good idea? Well let’s quickly go over some examples.

1) Additional Filtration: Intake filters themselves have many small “pores” that allow air to pass through the filter media but trap particulates. However, as these “pores” clog up with particulates you start introducing more restriction - which is not ideal for making power. Furthermore, as restriction increases so does suction strength - because your car still needs to flow X amount of air, and in order to do so the amount of suction (vacuum) will increase. This is not ideal because the increased suction will eventually allow particulates to get pulled past the pores and into your air stream therefore allowing unwanted debris into your engine. And the larger the particle size (bugs, leaves, large bits of dirt and sand) the faster the clogging occurs. This can all occur extremely quickly if you drive in an extremely dusty environment (Autumn in Canada comes to mind when all the leaves that fall off of trees dry up and creates that dry leaf dust that gets everywhere”, or pollen during the spring that coats absolutely everything), meaning you will have to clean your filters very frequently to prevent this issue from occurring. For instance if the amount of pollen and dandelion seeds outside is extremely high, the bottom of my stock filter can get coated after a few drives - which is absolutely horrible for air flow and would require quite a bit of maintenance if I wanted to keep it perfectly clean.

A better solution in my opinion is an intake Pre-Filter, this is because it can stop a lot of the larger particles from getting stuck in your intake filter “pores” in the first place by deflecting them (pre-filters aren’t designed to trap like filters are, they are designed to be smooth in order to deflect and not allow things to stick to them). The result is that the intake filter peak air flow is maintained at a higher level for longer, as less debris is getting stuck in the filter “pores”. This means that the suction doesn’t have to rapidly increase to compensate for filter blockage and the chance of something getting past your filter and entering your engine is decreased. This also means you don’t have to clean your filters as often and therefore can choose to extend your filter service interval if you desire - or even better keep it the same thereby allowing the peak air flow to always be in peak condition.


2) Additional Filter Protection: These Filter-Wears pre-filters are made from monofilament polyester (some tennis racket strings are made from this material) which is an extremely durable and abrasion resistant material. This means the Pre-Filter will be able to add an additional layer of protection to your filter, preventing it from being damaged - lets expand on this.

a) Debris Damage: If you have a front mounted intake (those mounted behind the kidney grilles) your intake filter is susceptible to alot of rock impacts - especially if you live in a country that uses gravel on the road in the winter time (Canada is a prime example of this). This can cause damage or even punctures to the filter media, and a pre-filter will help alleviate this type of damage - especially from the smaller rocks and debris.

b) Acid damage: Dead bugs that get stuck in your intake filter can eventually release acid (acetic acid is the main one) as they decay and this can damage and degrade your cotton intake filter media (this is another reason why you shouldn’t leave dead bugs on your clear coat because it can eventually “etch” into it). Again an intake pre-filter can help stop this by preventing bugs from getting onto the filter itself.

c) Water Repelling: Pre-filters add water repelling attributes to your intake filter, this prevents hydrolocking of your engine especially if you have front mounted intakes or a vented hood. Another benefit of protecting your intake filter (especially on oiled filters) from water is you prevent the “oils” from getting washed off of the filter media. This is particularly important because these “oils” are there to trap dirt and dust and are critical to the filtration capabilities of high flow oiled filters, so you do not want them to wash away in the rain.



Intakes that Would Greatly Benefit from Having a Pre-Filter:

Next I would like to briefly go over some intakes that really should have pre-filters.

1) Aftermarket Cone Filter Intakes:


Credit: Turner Motorsport https://www.turnermotorsport.com/p-5...-335i/?pdk=AwQ



Credit: Turner Motorsport https://www.turnermotorsport.com/p-5...-335i/?pdk=AwQ


Personally I believe all aftermarket intakes (in particular if there is a Pre-filter available that fits your filter you should get one) should be used with pre-filters to improve filtration. Any time you move away from an OEM paper filter towards a high flow cotton filter you will lose filtration in exchange for air flow - there’s no way around that, and how much filtration you lose depends on the quality of filter. So to mitigate any ill effects of losing filtration with an aftermarket filter, you should get a pre-filter to help.


2) Front Relocated Intakes: I believe any intake relocated to behind the kidney grilles should be used with a pre-filter with no questions asked. The reasons behind this is pretty obvious, front-located filters are extremely susceptible to rock or road debris damage, and are more susceptible to hydrolocking and exposure to water (which again can wash off the oils on oiled filters which is vital to filtration).


3) Open Cone Filter + Vented hood: cars with an open intake filter and a vented hood should have a pre-filter on them to prevent hydrolocking and exposure to water (which again can wash off the oils on oiled filters which is vital to filtration).



Filter-Wears Intake Pre-Filter on my Turner Motorsport Carbon Fiber Intake:

In the final section of this review I would like to show some images of the Filter-Wears pre-filter installed on my Turner Motorsport Carbon Fiber Intake, but at the time of writing this review I have not been able to install my intake due to a few issues with the intake (I will address this in the review for my intake) and the weather being -37C outside. So for the time being I will only be able to show the Pre-filter installed on the intake filter, and when I am able to install the intake I will add images of the pre-filter installed on my intake to the reserved post below.



Credit: F87Source



Credit: F87Source



Credit: F87Source


In the images above is the Turner Motorsport filter that comes with their open carbon intake for the N55 powered F series Bmw cars: https://www.turnermotorsport.com/p-5...-335i/?pdk=AwQ


My filter is still in its factory sealed cling wrap since I want to keep it clean until I install the intake, the cling wrap is quite tight against the filter so it shouldn’t impact pre-filter testing.




Credit: F87Source



Credit: F87Source



Credit: F87Source



Credit: F87Source



Credit: F87Source


Above are the images of the Pre-filter installed on the Turner Motorsport air filter. As you can see fitment is very good, the pre-filter is the perfect height, and width for the air filter and it fits very snugly and without massive amounts of slack. This should allow the water to run off instead of pooling - which reduces the chance of water being soaked through the pre-filter.



Water Repellent Testing:

Now I will perform a water repellent testing with the Filter-wears pre-filter, to do so I will be placing the pre-filter under a running tap and I will have a piece of toilet paper on the inside of the pre-filter to test if water is getting through. I won’t be using my actual air filter because I don’t want to wash off the oil and have to re-oil the brand new filter.


Credit: F87Source

Above is my experimental setup, the pre-filter and a piece of toilet paper (2, 2-ply squares folded up into 1 square). I will be running it under the tap using cold water at very low water flow rates - because I tried to do a fully on sink test and water deflected off the pre-filter and went everywhere and soaked my dry wall and phone. So I will only be doing a low flow rate water test.




Credit: F87Source


The first test is just with my hand inside of the pre-filter so you can see the water deflecting off the surface of the pre-filter. As you can see the pre-filter is VERY good at repelling water and preventing it from getting through. During this test my hand didn’t even get wet, but I know you probably want more proof so that’s where the toilet paper comes in.




Credit: F87Source


So here’s the test with the toilet paper, and I made a slight mistake here in that my fingers were curled trying to hold the toilet paper in place and that made a small pocket at the top of the pre-filter where water pooled right on top of the toilet paper. This allowed the toilet paper which was touching the pooled water to suck some through and that’s why you’ll notice that a bit of the paper and a bit of my hand was wet after pulling it out of the pre-filter. If the pre-filter was perfectly taut like it would stretch over an air filter, then the water would have not pooled and beaded off before it could soak through to the paper. But I couldn’t keep it taught without the paper moving around.


Credit: F87Source

Here’s an image of the crease I made in the pre-filter that allowed the water to pool.



Credit: F87Source


Here’s a video of the water testing being done with a piece of toilet paper. As you can see the central section of the toilet paper was perfectly dry, the only section of paper that was wet was near my middle finger and where the filter was creased.

Note: Ignore the area on the paper near my wrist and thumb that got wet when the water ran down the prefilter and then onto my wrist and into the inside of the pre-filter at the 9 second mark (for some reason imgur counts down instead of up so 9 seconds counting down)


Credit: F87Source

As you can see the water ran down my wrist and into my palm and thumb which got those areas of toilet paper wet, it didn’t pass through the pre-filter. My wrist was also wet at well further backing this up:


Credit: F87Source



So if you look at the center of the toilet paper where no accidents occurred (water running down my wrist or the crease in the pre-filter allowing water to pool) it stayed dry showing that the pre-filter was very good at repelling water. Even if you didn’t believe me and thought that water went straight through the pre-filter (which it didn’t), the amount of water that was on the paper is insignificant compared to the amount of water that was running on the pre-filter. So that still shows that the pre-filter was effective in deflecting the vast majority of water that reaches it. This overall should give you confidence that your intake air filter will remain dry and your engine will be protected from hydrolocking if water were to splash onto your filter.


Finally here is an image of the water droplets beading on the pre-filter:


Credit: F87Source

This shows that the water isn’t seeping through the pre-filter material.



But this should also show you the importance of having a properly sized pre-filter, because having a baggy pre-filter will form creases that allows water to pool and be absorbed right through the pre-filter if an absorbent material is pressing right up against the pre-filter in that section. So that’s why you should be buying a pre-filter from a company like filter-wears that has a massive size selection, because you’ll more than likely be able to get the size that you need. Rather than buying a pre-filter made for some other filter and trying to get it to fit.



Summary:

So that wraps up my review of the Filterwears Intake Pre-Filter, and all I can say is I absolutely love this product, the fitment, and most importantly the additional protection it provides to my engine.


If you want to buy a Pre-Filter for your cold air intake here’s a link to the Filterwear’s website where you can use their excellent fitment tool to find a Pre-Filter suitable for your intake: https://filterwears.com/


If you want to buy a Pre-Filter for your Turner Motorsport carbon fiber N55 intake here’s a link to buy the same Pre-Filter I have: https://filterwears.com/products/fil...10380516589615


Discount Code: Once again the Filterwears team was also kind enough to provide all the readers here on bimmerpost with a discount code for 10% off any purchase on their website. The code is: bimmerpost10.

Note: I do not make a single penny if you use this discount code, this was just a courtesy provided by Filterwears to the readers on bimmerpost and that is it.

[F87source]

Reserved for future posts.