Air Filter size options for FJ40 Chevy 350 conversion (1 Viewer)

[ElephantRebel]

Hello,

I'm trying to figure out the proper size filter(s) I could or should use. I believe I currently a 14 x 2 air filter.

First, am I measuring the filter correctly (see photos) and is this the optimal size for a 350 conversion? Could I go bigger/ taller?

Any input would be appreciated

 

[B y r o n]

See post #16.

 

[lcwizard]

depends how much HP you want. On my tbi350 , I would run out of air pulling a steep grade with a small trailer at about 60 MPH
with the stock gm 14 x 2. I went to a 4" tall and couldn't starve the motor anymore. A fuel injected motor will let you know quickly
if you aren't getting air. The O2s will back off the gas if the mixture gets too lean regardless of your throttle foot position

 

[ElephantRebel]

depends how much HP you want. On my tbi350 , I would run out of air pulling a steep grade with a small trailer at about 60 MPH
with the stock gm 14 x 2. I went to a 4" tall and couldn't starve the motor anymore. A fuel injected motor will let you know quickly
if you aren't getting air. The O2s will back off the gas if the mixture gets too lean regardless of your throttle foot position

I'm thinking of going to 4 inches but I have a holly carburetor...so no fuel injection intelligence to auto adjust mix...you have any knowledge or suggestions when working with the latter?

 

[BrianSanDiego]

14x4 here...
I went with the tallest filter that would fit for a couple reasons, longer life and less flow restriction. I use a K&N foam outer filter (not shown) to keep water off the paper element, and it also extends the life of the filter. Also quick and easy to clean with water.
I always run a paper filter on offroad vehicles, and find zero dust or grit in the intake. Before I knew better, I ran a K&N gauze filter on my 4runner and found a load of grit in the intake after a desert trip. So no more oiled gauze filters.
K&N pre-filter works great in combination with the paper though.
Also, you filter might hit the hood if it's too tall. Depends on your engine placement and air filter housing.

 

[LandCrusher'70]

I also run a 14x4 (WIX). It just fits under the hood. Plenty of airflow. I’ve got a UNI foam pre-filter on my shopping list.