You've heard the hype and the
claims, but does anyone know for sure whether cold air
induction kits actually offer any benefits over the stock
We decided to find out with a quick test of the Moroso
High Flow Air Induction system. The kit, consisting of
a conical K&N filter and a molded tube, positions
the filter in the fenderwell, eliminating the stock air
box and panel filter. Many companies make similar so-called
"fenderrwell" or "cold air" induction
Cold-air vs. Ram-air
An important distinction must
be made clear between the terms "cold air induction"
and "ram air induction".
A cold-air kit simply implies that the air is drawn in
from outside the engine compartment (i.e. the filter is
not sucking up the heated air around the engine.)
induction, on the other hand, implies that the air
is being forced into the air cleaner assembly when the
car is in motion. This is typically is achieved by placing
a scoop or tube facing the front of the vehicle.
In a ram air system the engine benefits from a slight
increase in air pressure, like a natural supercharger.
A cold air system does not have this effect.
We know that ram-air systems do work. We tested
such a system on a carbed 302 and got impressive gains.
The question in this article is whether or not there is
any benefit from simple putting a filter in the fender.