Re: K&N filtercharger

[Dan Bocek <dan@di.com>]

> On the turbo cars, even stock, the K&N is a very good way to
> spend your first tweek dollars......  It does make a difference.

Not meaning to blast a hole in the seeming love of K&N filters here, but, 
as the old saying goes, you don't get nothin' for free.  I seem to recall 
some traffic earlier on this list regarding some tests comparing K&N vs. 
stock filters in effectiveness in keeping crap out of your engine.  Seems 
to me that the K&N was not as good a *FILTER* as stock in dusty 
environments, with some engine damage resulting in extreme cases.

Now I'm not the original owner of my '83 UrQ, but when I got it, it had a
K&N installed.  As I was doing the engine rebuild, when I pulled the old
turbo for an inspection, I noticed that the compressor wheel was chipped
enough to give me the incentive to go through the major hassle and expense
of going with the RS2 turbo.  It doesn't take a big piece of dirt to chip
a compressor wheel spinning at 100,000 rpm (or, for that matter, it
doesn't take a big chip in the compressor wheel to throw the whole thing
out of balance). 

I also noticed something odd about all of the intercooler pipes. 
Normally, these will have a light coating of oil on their insides due to
the PCV being piped back into the intake system.  All of my pipes had a
nice gritty feel on their insides due to lots of fine dirt which had
gotten trapped in the internal oil coating. 

Now of course I can't say all (or any) of this was due to the K&N (for 
all I know, the previous owner could have run the thing without a filter 
for a while), but knowing how festidious he was, I doubt he ever ran it 
without the filter.  I do know that I am now running a stock filter, and 
keeping the K&N for the occasional track event.

P.S. Yes, I checked my K&N for rips, tears, and holes.  I didn't find 
any, and yes, it was properly oiled.  Makes ya think, doesn't it?


                                                         Dan Bocek
                                                         dan@di.com