[A4] Pre-chip checklist

thejimrose thejimrose at gmail.com
Fri Feb 2 14:06:24 EST 2007

i disagree on the k+n. the maf in the a4 is sensitive to oils [they'll
ruin it] and using an oiled filter is asking for screwy maf's. no
matter what k+n says an oiled filter WILL blow oil into the intake
[since you know.. there's AIR flowing thru it] and spoil the maf. the
maf  can cause screwy running w/out throwing a cel.

there really are not any meaningful gains to be had my modding the
stock airbox on the a4. it's actually a very well designed piece,
there isn't a single one out there in the aftermarket that makes any
power gains, just more noise. ive tried a few variationson mine [with
an aem dry paper cone filter] and alls it does is make the induction
noise much louder. you might try an itg, or similar dry paper or foam
drop in filter but it's not going to do anything. other then let more
crud into the motor.

keep in mind that you're going to just about double the pressure in
the intake - if there are weak links [at 110k there are] you're going
to exploit them.

so a thorough tune up and replacement of anything in the intake path
is a great idea. some things off the top of my head..

vaccum lines - ALL of them [ the stock cloth braided rubber stuff
holds up really well for years]. spend some $ on nice aba stainless
mini hoseclamps and clamp everywhere. there are a few that are a REAL
PITA to get at on the turbo and at the n75 valve. pull out the pass
side headlight to make it a little easier. i would stick with the
stock n75 [vs the 'race' valve] as the boost curve is much more
conducive to driveability.

change all the filters, including the fuel filter. it's supposed to be
lifetime but they clog.

upgrade the hose clamps in the intake path with these:

there's about 8 of them - airbox to turbo, the intercoler xover pipe,
the IC, and at the throttle body. measure them bc there is a few
different sizes.

good time to do new plugs.. ngk bkr6's gapped to .24 outta be on the
$. or whatever the chip makes recc's.

DEFINITELY install a boost gauge. it's a great thermometer for what's
going on in the engine. you should be pulling ~20inches of vaccum at
idle, and it'll boost to about 16-18 psi. if you have vacc leaks and
or arent making correct boost, there's no way to know w/out the gauge.
you can get a vdo vision with a tubing kit from jegs or summitt for

you could clean your maf since you're going to be in there. spray it
down with a good residue free electronics cleaner.

the tt dv is a great upgrade.

check the pcv and egr [pancake valve] systems for weeping oil, leaks, etc.

a phenolic intake spacer is a nice cheap upgrade if you're pulling the
intake apart. keeps the manifold cooler. a well spent $50 IMO.

the other big improvement would be to upgrade the exhaust, but that's
probably next on your list? =)

give that a go and let us know how it turns out.

good luck,

Chuck Norris counted to infinity. Twice.

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