Does it make a difference in where the air intake is?

[Spector]

I believe that it makes a difference in terms of performance, that is you want the coldest air possible coming in, especially for turbos, but in terms of dirt ingestion does it make a difference where the air intake is located.

Reason I ask is that of the five cars I service (all driven in the same general area, basically urbal/rural no dusty raods etc.) over the course of a year a couple of them will have absolutely filthy air filters when removed and the other three basically clean. Mileage similar within 5000 miles or so.

So, does the placement of the air intake for the filter make a difference as to how much dirt is sucked into the filter????? All new cars seem to be in front to the side but does the shape, etc. and where it faces make any difference?.

 

[NThomas]

yes it does
On my honda civic it came w/ a resinator box that
would muffle the air intake. most of the dirt would get stuck in a seperate chamber before it hit the air filter. i took this off to get more air intake and the filter gets alot more dirt in it.

 

[Rick in PA]

Interesting question, provokes some thought.

A little story from my brother: a long time ago the computer manufacturer he worked for was having problems with disk crashes (this was before the ultra clean environment that disks live in nowadays). They finally determined the cause, cooling air drawn in from the base of the unit carried dirt with it and caused the crashes. The air was exhausted at the top of the unit. A study showed particle density increased as you approached the floor (makes sense). So they reversed the cooling air flow, drawing in cleaner air from a heigth off the floor, and fixed the problem.

I suspect that the closer to the road the air intake is, the greater the dirt load it carries. I've seen pictures of old tractors where they mounted an intake snorkle that rose above the tractor. This was an effort to draft cleaner air outside the dust churned up by the tractor.

I also suspect that if the intake is drawing air from the vicinity of the wheel, this would be bad. Wheels churn up an incredible amount of dust. Where are the intakes on the various cars you mention?

It's very important to feed any filter as clean an air (or oil for that matter) as possible. Filters are typically rated XX% at a X micron. Therefore, if it has relatively dirty input, the output will be dirtier in a relative sense. For example if I feed the filter a given airflow with 100 particles at X micron and the filter is 98% efficient, on the average 2 particles get through. Now if I feed the same filter the same airflow with 10,000 particles, on the average 200 get through.