Engine Filtration

[Chimi]

What up Gang,

Figured id start a thread about engine filtration. The goal is maybe create a reference that others can look back on based on all your collective experience. I'm no master just like to nerd out on shit.

I was doing some research to combat the Moon dust we have out here. Based on what ive read it seems like Donaldson makes some good shit and running something like a PSD12 dual stage filter would match my CFM requirments for a NA 402 LS. Can even run a partical separator style pre filter so help it not pack up quite as much. I havent yet called them to confirm.

What does everyone else run?

 

[dwphoto]

What up Gang,

Figured id start a thread about engine filtration. The goal is maybe create a reference that others can look back on based on all your collective experience. I'm no master just like to nerd out on shit.

I was doing some research to combat the Moon dust we have out here. Based on what ive read it seems like Donaldson makes some good shit and running something like a PSD12 dual stage filter would match my CFM requirments for a NA 402 LS. Can even run a partical separator style pre filter so help it not pack up quite as much. I havent yet called them to confirm.

What does everyone else run?

Running k and N filter on 4Runner crawler with the 3rz so far so good

and a AME dry flow filter with a prefilter on mouse with 22re. Try to wash out after each trip slap it back on and cake it back up on the next adventure.

 

[Tree trunk]

I have a Donaldson cartridge filter on the bronco, no dirt miles on it yet so I can’t talk about performance. I’m sure it will do better than the specter cone filter that was on there before though
-it’s big, so if your tight on space already fitting a big cartridge filter might be difficult.

My dad has a K&N filter on the jeep, no filter housing so it’s open to the engine compartment. It gets pretty dirty especially because he’s venting the crank case to atmosphere. (It’s on the list to hook back up to the intake)
But it seems to work fine though if I was to do it again I would try to stick a cartridge filter in there to avoid any issues with getting wet.

 

[DialedShockPrep]

One HUGE thing that i see overlooked on a lot of customers cars is having a volume of filtered air ready for the engine to draw from. If you take a look at most every single OEM vehicle on the road, they have a long tube to an airbox and most typically the airbox has a large empty void below the filter. This section of filtered air is essential for engine performance so the engine can quickly pull in a bunch of filtered air so the negative pressure doesn’t immediately drop as the engine raises RPM’s. Due to space constraints it’s pretty common to see a small intake tube, or even no intake tube and a smaller cone filter strapped right onto the throttle body. This is the equivalent of trying to run a marathon with a pillow duct taped to your face. And this issue is compounded with bigger displacement engines or higher flowing heads and such that require a larger volume of air.
There are formulas you can find online to see if your filter setups are capable of flowing enough CFM to keep your engine breathing happy at higher RPM’s, and remember that those formulas are for clean filters, NOT dusty silt filled filters so a good rule of thumb is x2 filtration surface area than recommended.

 

[84Prerunner]

One HUGE thing that i see overlooked on a lot of customers cars is having a volume of filtered air ready for the engine to draw from. If you take a look at most every single OEM vehicle on the road, they have a long tube to an airbox and most typically the airbox has a large empty void below the filter. This section of filtered air is essential for engine performance so the engine can quickly pull in a bunch of filtered air so the negative pressure doesn’t immediately drop as the engine raises RPM’s. Due to space constraints it’s pretty common to see a small intake tube, or even no intake tube and a smaller cone filter strapped right onto the throttle body. This is the equivalent of trying to run a marathon with a pillow duct taped to your face. And this issue is compounded with bigger displacement engines or higher flowing heads and such that require a larger volume of air.
There are formulas you can find online to see if your filter setups are capable of flowing enough CFM to keep your engine breathing happy at higher RPM’s, and remember that those formulas are for clean filters, NOT dusty silt filled filters so a good rule of thumb is x2 filtration surface area than recommended.

This would be fun to test. Unless you have a very restrictive filter, I don’t see the intake tube volume making any noticeable difference. The volume of air an intake tube holds is very little compared to what an engine uses at WOT. Of the air was somehow compressed that would change things but we know it’s not.
On a MAF intake setup the tube does smooth the air flow to get an accurate reading across the sensor but that’s not directly related to the air volume.

 

[84Prerunner]

All of this out of the small power core filter on a can an after the 1000

 

[84Prerunner]

 

[Exploder_M]

I work with construction equipment and those power core filters are the best that I have seen out there. They barely ever are caked with dirt/dust compared to round paper air filters like the one next to the brake cleaner. It seems like that prechamber box on the left side of the actual plastic filter housing is what gets rid of most of the dirt dissipated and falls out the drain hole on the bottom before it gets to the filter. Just about all construction equipment use paper filters and they live in the dirt.

Foam or k&n type filters are trash in my opinion. They are too porous and some of them rely on oil to catch dirt particles. I use Uni foam filters that are oiled on my dirtbike but Always put an outerwears prefilter (similar to pantyhose)on it to catch as much as it can before the filter.

Paper filters can hold a lot more dirt than people think. They should be tapped out routinely to remove dirt and they are cheap to replace. Some old timers use an air hose to blow paper filters out but this can put small holes in the paper filter media and then allow dirt to flow right into the engine. There is no reason to blow a paper filter out, just replace it and move on.

 

[84Prerunner]

Aftermath of running a kn with a uni prefilter.

 

[84Prerunner]

Same truck and intake with a dry filter

 

[Exploder_M]

My point proven! Thank you.

I did a similar test with an old turbo diesel car where I put a gob of grease inside the filter housing and ran the engine for a couple months with a properly oiled k&n filter. Then I did the same test but with the stock factory paper filter. The grease was coated with dirt and debris from the k&n filter test.
I proceeded to throw away all 3 k&n filters from all 3 of my cars that same day and put paper filters back in.

 

[DialedShockPrep]

This would be fun to test. Unless you have a very restrictive filter, I don’t see the intake tube volume making any noticeable difference. The volume of air an intake tube holds is very little compared to what an engine uses at WOT. Of the air was somehow compressed that would change things but we know it’s not.
On a MAF intake setup the tube does smooth the air flow to get an accurate reading across the sensor but that’s not directly related to the air volume.

Old Boss’s ranger had a cone filter right off the front of the engine. Dyno guy stuck a 4ft piece of aluminum tube on the intake and then put the filter at the end and it definitely changed the way the engine dyno’d. Throttle response was snappier and it built power more quickly. I don’t recall exactly the difference but there was a small difference lol

 

[84Prerunner]

Old Boss’s ranger had a cone filter right off the front of the engine. Dyno guy stuck a 4ft piece of aluminum tube on the intake and then put the filter at the end and it definitely changed the way the engine dyno’d. Throttle response was snappier and it built power more quickly. I don’t recall exactly the difference but there was a small difference lol

I wonder if it had something to do with turbulence between the throttle body and filter flow part.

 

[Chimi]

Right on, super interesting stuff, thanks for all the input!

 

[Prerunsilverado]

My point proven! Thank you.

I did a similar test with an old turbo diesel car where I put a gob of grease inside the filter housing and ran the engine for a couple months with a properly oiled k&n filter. Then I did the same test but with the stock factory paper filter. The grease was coated with dirt and debris from the k&n filter test.
I proceeded to throw away all 3 k&n filters from all 3 of my cars that same day and put paper filters back in.

I too have been disappointed with K&N and also went back to the stock paper filters.