Best Induction Kit / Set up

[jondee86]

Haha... that mkiv test was one of the things that made me to decide to
use Apexi filters

Now in the world of statistics 97% vs 99% may not seem like a lot of
difference, but if you look at these numbers in another way, the difference
is considerable. Let's say each filter is fed 100gms of dirt and one filter
collects 97gms and the other collects 99gms.

This means one passed 3gms and the other 1gm of dirt into the intake.
That's 3 times as much dirt, and since engine wear is more or less
proportional to the amount of dirt ingested by the engine, the engine with
the 97% efficient filter will wear out 3 times as fast.

Measuring the actual particle sizes that pass thru the filter requires a lot
more time and effort with high tech equipment, and is rarely done with
simple comparative testing. The larger the particles in the test dirt the
easier they are to filter out of the airstream. So it is safe to say that the
particles that pass thru the filter are at the finer ones.

However, it is also safe to say that all dirt that passes an intake air filter
in normal use will be bad for the engine... so more dirt equals more wear.

Research to find the particle size that is the most harmful to the engine is
a laboratory level experiment and is carried out using test dusts of very
specific particle sizes. ASTM filter test dusts are done with dusts that
contain a range of particle sizes representative of real world road dust.

I might add that I don't personally have a beef with K&N filters. I'm sure
they have applications in racing where car owners are prepared to trade
off higher engine wear against claimed power gains from a higher flowing
filter. It is (or was) a free world In fact many race engines run without
any filter at all for the same reason, but those engines will be pulled down
regularly for other reasons, so a bit of extra wear is not an issue.

Cheers... jondee86