Stock fuel filter, what micron?

[A4 TSCHUSS]

I will be installing my new Bosch 044 fuel pump inline soon and just thought that I should put it in the location of the stock fuel filter and then relocate the filter. That filter is pretty big and will most likely not fit anywhere else so I decided I am going to get a smaller in stature fuel filter with -6an fittings to fit inline with my setup somewhere.

Now I just need to determine how low of micron rating I should be getting to be ok and then also find one that will support the high fuel pressure I will be running while in boost (fuel psi in the high 80s).

Something like this Summit one. A lot that I see with -6an fittings are 40 micron but I have read it is recommended to have 10 micron but I am thinking the 40 micron will be sufficient.



I am loooking at a Trick Flow that is 40 micron and good to 300psi.

[dougyfresh]

How about whatever filter that Jet Jockey installed?

[A4 TSCHUSS]

No clue about what he has. I have seen some of his threads but I don't keep up with them reading every page.

[dougyfresh]

Try reviewing this (I can't see the images so I'm not sure if the filter is documented): http://www.audizine.com/forum/showthread.php?312455

[AudiA4Turbo22]

I think the industry standard is 10 microns. Even APR uses 10 Micron for testing their fuel pumps.

The issue with going with the smaller fuel filter is the cost. Also, I've only been able to find these in -8AN and -10AN none in -6AN. These things cost a pretty penny to say the least.

http://www.034motorsport.com/fuel-in...ron-p-437.html

http://www.jegs.com/i/Aeromotive/027/12301/10002/-1

[AudiA4Turbo22]

Try reviewing this (I can't see the images so I'm not sure if the filter is documented): http://www.audizine.com/forum/showthread.php?312455

My second link is that exact filter it is a 10 Micron filter from JEGS with -10AN fittings

[BARRY]

the problem with those small filters is...once they start clogging they REALLY limit flow. larger filters have plenty of surface area to still allow adequate flow. in the race cars i've built we've always installed fuel pressure gauges in the case that these filters clog up due to the foam from our fuel cells slowly deteriorating.

[dougyfresh]

the problem with those small filters is...once they start clogging they REALLY limit flow. larger filters have plenty of surface area to still allow adequate flow. in the race cars i've built we've always installed fuel pressure gauges in the case that these filters clog up due to the foam from our fuel cells slowly deteriorating.

Good point.

I'd find a way to use this filter then. There is room. You just have to hunt and/or make it.
http://www.034motorsport.com/fuel-in...mbo-p-469.html

[A4 TSCHUSS]

He used an Aeromotive. Same deal I was showing but Aeromotive brand. I didn't see a mention on what micron he chose though.

[AudiA4Turbo22]

He used an Aeromotive. Same deal I was showing but Aeromotive brand. I didn't see a mention on what micron he chose though.

I believe they are color coded the JEGS link I posted is the same one. It states it'll flow for 2000HP

[A4 TSCHUSS]

On Aeromotive's site I saw they have a 10 micron and then a 40 micron "high flow/cleanable" available. Don't know about a color though. What do you mean, like one housing is black while the other is red or something like that?

On the filter page it showed a few different ones and the red were 40 and some of the black said 10 so I don't know if that means that the red are only 40 micron or what. And then there is the 100 micron prefilter that is red also.

[AudiA4Turbo22]

^^I take that back, I went onto their website, and it seems that the inner fabric can be changed to suit your needs. The 10 Micron can only be placed AFTER the fuel pump according to them.

http://aeromotiveinc.com/products-pa...d-fuel-filter/

I guess it depends on how much flow you want from the filter.

[AudiA4Turbo22]

Oh and as you go up in microns I guess the more it flows and less it filters. So I think the lowest(10 Microns) is your best bet to keep your motor clean. The 10 micron should flow for 2000HP

[A4 TSCHUSS]

Yes it would be after the pump, I just need to figure out if using a 40 is ok, which I assume would be since so many different companies offer a 40 for "high flow." The problem I am seeing also is in order to get the -6an it is only the 40 so I think I am limited to that and it is also only 1 1/4 diameter housings. I would like a little bigger than that but they are claiming a high flow amount through it still so I guess it would be ok.

[AudiA4Turbo22]

I just read up a ton on this subject and it seems that a 10 Micron is really the way to go for fuel injected cars as a 40 micron is more aggressive. I'm in the process of finding a 10 micron filter with -06AN fittings for you as I saw a couple but they wouldn't flow enough. The important thing is to see how much the filter can flow. If the max is 75 psi you need to know what the demands from your car are. At regular flow in may be like 43.5 psi so that would allow for a bit more than 30 psi of boost so anything above would need a higher flow rating.

[A4 TSCHUSS]

Good point.

I'd find a way to use this filter then. There is room. You just have to hunt and/or make it.
http://www.034motorsport.com/fuel-in...mbo-p-469.html

Just saw this post. I have that filter in my car right now. It is way to big to fit anywhere. It doesn't even fit in the stock filter location actually. I had to tie wrap the housing closed since it wouldn't go tight enough to screw it back together.

[A4 TSCHUSS]

I just read up a ton on this subject and it seems that a 10 Micron is really the way to go for fuel injected cars as a 40 micron is more aggressive. I'm in the process of finding a 10 micron filter with -06AN fittings for you as I saw a couple but they wouldn't flow enough. The important thing is to see how much the filter can flow. If the max is 75 psi you need to know what the demands from your car are. At regular flow in may be like 43.5 psi so that would allow for a bit more than 30 psi of boost so anything above would need a higher flow rating.

The ones I read say 130gph at 75psi, the higher pressure I don't think would make it drop flow much and that is 492lph so that is way beyond what I need.

[AudiA4Turbo22]

^^ok then you are set. I'm new to the whole fuel pressure thing so studying it. However, I suggest you stick to a 10 micron filter.

[A4 TSCHUSS]

I just have so many issues, 10 micron from what I have found means bigger than -6an fittings or I believe something like the Aeromotive can have -6an conversion to fit their bigger threading. But then I have the issue of a bigger filter and space constraints. But at the same time I am on the fence about having a smaller filter vs bigger for the surface area of filtering material, and then in the case of the Aeromotive and fittings I would be looking at like $130 for a filter shipped to me instead of like $40 I just can't decide what to do. I wish I knew that I would be ok with the smaller filter and it not clogging up or something in a month and then the 40 micron being good enough.

[BARRY]

^^I take that back, I went onto their website, and it seems that the inner fabric can be changed to suit your needs. The 10 Micron can only be placed AFTER the fuel pump according to them.

http://aeromotiveinc.com/products-pa...d-fuel-filter/

I guess it depends on how much flow you want from the filter.

it'll have to be after the pump. if you put it before the pump and there is a restriction you will burn up your pump.

plus small things won't hurt a pump so its ok.

[A4 TSCHUSS]

I found this and it is making me feel pretty comfortable with using a 40 micron filter. I see there being zero issue of something smaller than a human hair if it were to get past this filter causing a clogging issue in a high pressure injector.

Diameter of average human hair 70 microns
Lower limit of visibility (naked eye) 40 microns

[FORCE_FED_DUB]

I'd go with a biggest filter you can since you don't want it clogging quickly, and since you're already doing a lot of work on your fueling system I'm sure you could find a place for a stock size filter, like under the rain tray or under the frame rail in the bay?

[A4 TSCHUSS]

My fuel system has been in place for a year. I am not running any lines so where they currently are is where they will stay, and there is no room anywhere for that big filter. I am simply undoing the -6an fittings on my current filter (the one doug posted a link to from 034), putting the 044 in its place and then cutting the stainless braided line and putting new fittings on it and a filter in line somewhere. This will most likely be right in front of the pump but it will have to be under the plastic that runs the length of the car and there isn't much room that is why I have the need for a smaller sized filter. I looked around and there really isn't anywhere for it.

[FORCE_FED_DUB]

What about between the pumps?

[A4 TSCHUSS]

There just isn't room that I remember. Have you visually seen the fuel pump in our car? Well this one from 034 is bigger so it is very hard to fit it somewhere. The fuel lines come straight down the front of the tank and then curve and go right in to the filter (where the pump will now be) so there isn't room. Then there is a few inches in front of the filter and then you are slap up under the car where the fuel lines run under that plastic. There might not even be enough room without the filter bulging the plastic down even with a small 1.25" diameter filter. I will have to get under there again with stuff taken apart and look but almost sure there isn't room.

[dougyfresh]

There is plenty of room. You just need to reroute some lines (even though you don't want to do that).

[20vturbo]

don't you have a filter before the first pump, why another one before the second pump??

[A4 TSCHUSS]

The filter before first pump is a pre filter. Something like the 100 micron type of deal talked about before just to keep big stuff from entering. Then there is the stock filter after the pump that is much smaller filtration (10 micron). I will be running a filter after the two, not between them which will replace the stock filter since the new pump will be inthe stock filters spot under the car.