Does anybody have an idea of what the micron rating of a stock fuel filter is. I bought an inline filter today thinking it was 10 micron but its actually 30. Is that ok to use after the pump? Thanks

 

The stocker is quite coarse, that's why it last so long, my guess is 100 micron, but I would also be curious to know the exact number. 10-30 micron is definitely an upgrade from stock, I run and Aeromotive 10 micron and change it every 5k

 

Thanks man I thought I wasted 90 dollars. I just dropped my fuel lines and brazed on the -6 fittings from garfinkle. I thought why not add this now. I hate going above my diff when I see black widow webs by it.

 

You need a fine filter after the pump, if you look in Bosch literature, they recommend somewhere around 10 - and they used to (still do?) supply one for this car. They also have a spec for before the pump, which is closer to the figure quoted.

Other aftermarket stock replacement ones for the FD are very fine too....and I don't think Mazda would be in the habit of supplying something crap in an important area like this.

 

Yea but do you think the 30 micron is comparable or better then the stock filter? I know aftermarket everybody runs 10 micron but I messed up. If 30 is still better then stock I have no problem running it. I feel the mazda filter cannot be to fine because of the longevity of the filter. Any thoughts?

 

Yes.

Most aftermarket fuel filters start at 30-40 micron and go up to 200 micron. Some people NEVER change their fuel filter, so fuel filters for passenger cars have to be relatively coarse mesh, or they would load up in short order (< 10,000 miles)
http://www.wiremesh-cn.com/wire-mesh...lter-paper.htm

If you really want to know, cut open a stocker and send the filter media off to be analyzed

Actually, few people run 10 micron, and most racing filters are 100 micron. I installed the Aeromotive 10 micron element because I want to keep as much crap as possible out of the injectors, and I have it mounted on the rear subframe where it's a snap to change

 

I can tell you a stock replacement pressed steel one is rated at 7 micron.....will let 15 micron through, I find it unlikely they specced better than Mazda and fuel filter standards are pretty universal.

Here's some Bosch standards.....

http://apps.bosch.com.au/motorsport/...uelfilters.pdf

....no need to think the "motorsport filter" is somehow better either, they are passenger car filters in another range.

Nominal 35 micron will let particles of 80 to 100 through, well into the visual range and when you see the amount of garbage going through the system....

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/changed-fuel-filter-today-check-out-827434/

 

Not buying it, I want to see proof

 

Suppose it's OK to have an amount of skepticism, but riddle me this, why would Mazda, uniquely on the planet as far as I can tell, be the odd man out on efi componentry?

Anyhow the best "proof" I can come up with is whats written on the box. The company doesn't have a web presence as far as I can tell, but can give you a local phone number if you want to take them to task.

Anyhow, for your info - Cooper filters # WZ401. Another local, Ryco, did a stock replacement too, Z401, they happen to have a web site with contact details, so perhaps there's more info there if you want to pursue it....

http://www.rycofilters.com.au/

If you can lay hands on a Bosch efi catalogue or their automotive handbook, there's a deal of information on why fine filters are placed before injectors.

 

Mesh size is written on the box? Granted I haven't purchased a stock fuel filter in ages, but I don't recall seeing that information.

 

Heres what rc engineering said:

Hello,

The 30 micron rating should be fine. If you are using regular/race gas, we suggest using the paper element if possible.

Thank you for your interest in RC Engineering. Please feel free to call or e-mail us with any further questions you may have.

RC Engineering, Inc.
20807 Higgins Ct.
Torrance, Ca 90501
T (310) 320-2277
F (310) 782-1346