So I am now finally getting around to putting a fuel filter on my car (I know, I know). My car has 3/8" hard line the whole way to a Holley 110gph mechanical fuel pump. I'm pretty sure that is the pump I put on it, it was the largest mechanical pump Holley made(at the time) that you could run without having to also run a regulator. I just have 3/8" line running from the pump to the 1050 Dominator. I was looking at putting a Holley Dominator fuel filter between the pump and the carb but am unsure how many microns I should go with (I was thinking 40). I don't want to go too small with the microns and have my carburetor starved for fuel but at the same time I really need to get a filter in there lol. Any advice/help is appreciated, thanks!

 

Rookie suggestion........If you installed a metal (rather than a plastic housing) fuel filter in the soft line between the gas tank and the frame, you would save the whole supply line/fuel pump/carb from becoming contaminated if you ever bought "bad gas".

A pressure gauge at the carb would let you know if the fuel filter is becoming "stopped up"-----the gauge would show a lower reading.

I know little about microns,but I would think that the filter should be able to block particles that would clog the smallest passageways that are inside the carb. Example: .010" diameter passageway would require a filter that would "catch" particles much less than .010" in size.

According to the web, a 40 micron filter would catch particles .001" in size which is about the size of ONE particle of pollen (VERY small).

If your filter became clogged in less than a year (using "good" gas) you could be sure that you need to go with at least a 100 micron filter (catches particle .002" in size/still very small even though you double the Micron number)

The only time I have ever had a clogged fuel filter was when the gasoline I bought had WATER in it which cloggedthe filter within 10 miles after refueling.

I have changed a fuel filter as routine maintenance and found sand in the filter upon cutting it open to inspect it.

ALWAYS carry a spare fuel filter (and a fire extinguisher for safety).

 

you may want to read this before putting a filter on the inlet side of a pump
https://aeromotiveinc.com/fuel-filtration/

 

Mel, I could be wrong but I believe the position between the carb/fuel pump is the outlet side and the position fuel pump/fuel tank is the inlet side. The article you mentioned talks about not putting a 10 micron filter on the inlet side (between the pump and tank) I believe because a filter like the 10 micron is for very fine filtration and would plug up easily. I think typically you would run a 100 micron between the tank and pump and then a 10 or smaller between the pump and carb/efi if you are picky about filtering your fuel. I really just need to get something in there lol. Hopefully someone will chime in if I am incorrect.

 

https://rspimages.holley.com/162-551.jpg?width=583

100 GPH HP Billet Fuel Filter

Street/Strip Carbureted Applications Post Filter 40 Micron

PART# 162-562


Suggested Retail: $79.68
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Features
Overview
Specs

•Black anodized body and clear anodized end caps for corrosion resistance and good looks
•Female 3/8” NPT inlet and outlet
•40 micron stainless steel woven mesh element
•Measures 3.5” long and 1.5” diameter
•Recommended as a post filter (after the pump) in carbureted applications


I have the same Holley pump you have. Here is the filter I'm using, just a suggestion. I'm at 486hp, but this should be able to feed much more. What kind of power (fuel consumption) are you making?

 

I have used Earls fuel filters for a long time. Not too expensive and gets the job done. Goes from the fuel pump to carb.

http://www.jegs.com/i/Earl%26%23039%...30206/10002/-1

 

To be honest I dunno how much horsepower I have, it's probably between 525-600 horsepower at the motor. The filter that you mentioned sounds like what I am looking for. What kind of lines/connections are you running between the pump and carburetor?

 

What I have is "optimal overkill" for a 385 stroker. But it would allow for a lot more hp if I ever want to go there. Every line and connector is no less than 3/8" inside diameter, and there are no hard 90* bends. I used earls 3/8" NPT nipples on the filter, and I found some curved 90* brass nipples for the pump. I'm also using very sturdy clamps built in the 70s, with fuel injection liners. I tried some fuel injection clamps from NAPA but they bent and stripped way too easy.

 

This is an old photo, sorry. First mock up of the plumbing. Made a few changes since 2013.

 

That's a nice clean setup, I like it a lot! I think that is the fuel filter I am going to go with. Thank you for the picture and your help.

Thanks everyone for all of the help thus far

 

Good info.....so that's why they recommend 100 micron filters between the tank and the steel line-----to prevent starvation of the pump and premature filter clogging.

If I am "halfway paying attention "I will notice a lack of engine power and a carb pressure gauge showing a lower readingbecause of a filter that is beginning to clog, then I will be able to replace the filter/flush the tank if needed before the pump fails (On all military aircraft there is a quick drain/fuel sample petcock under the tank at the lowest corner to flush water/particles out of the tank after each fill-up to prevent filter clogging)

Personally, I would rather clog a under-tank filter because of trash in the tank rather than ruining a quality mech. or electric fuel pump by having a filter between the mech. pump and the carb.

 

I agree there's no replacement for doing it right! I was using a clear filter when I had the 350 and barely a speck ever appeared. As long as I have the original gas tank I will always have a good magnet stuck to the bottom of the tank to hold and keep any iron based particles out of the line. A little extra measure of prevention.