more questions about RE: Custom exhaust tuning...

[Beatty, Robert]

Scott or anyone else for that matter,

I'm looking at buying Stebros exhaust for my 87 5ktq or putting a custom
system in as the stock system is needing a new muffler anyways and since i
have chipped the car, the exhaust is something i want to do anyway.  Do you
have any experience with the Stebro system on the 5k and how is it as far as
noise goes?  I do NOT want a loud riceboy exhaust, I just want more power
out of the car, it can be totally silent for all I care.  Anyone have any
btdt?

Thanks in advance

Rob

-----Original Message-----
From: QSHIPQ at aol.com [mailto:QSHIPQ at aol.com]
Sent: Thursday, February 22, 2001 12:06 PM
To: spokes at mail.the-wire.com
Cc: audi20v at rennlist.org; quattro at audifans.com
Subject: RE: Custom exhaust tuning... help needed


Common problem, turbo or N/A I5 Audis.  The mid muffler is what tunes out
the 
resonance at highway speeds, however it also sucks midrange and highend 
power.  A couple of things you can do:
Put the cat back in, it also muffles sound.  High flow cats are best for 
this, I've found good luck using 3in cats on 2.5in systems (this brings the 
"urgent" tone down).  This also works in the center muffler application.
The 
best muffler for the center in terms of height and clearance is the 12in 
Borla XR1.  Again, going with the 3in version of this will create a lower 
tone, and really address the midrange drone, without sacrificing power.  As 
far as the rear muffler, I use the Borla (expensive) or the walker dynomax 
(best b4b) ultraflow.
As for what you have stock to work with, I haven't had a lot of luck using 
any "glasspack" type mufflers in the audi I5, they don't really do much in 
terms of quieting this unbalanced motor pulses.
As a rule, deleting the center muffler gives you great gains in midrange and

high end flow, but *always* at the expense of the sound right where you
drive 
the most often (a subchapter of Murphy's law applied to audis).  

HTH

Scott Justusson
QSHIPQ Performance Tuning
Chicago
'87 5ktqwRS2 10vt w/ 3in turbo back exh, 3in high flow cat, 3inxdual2.5
borla
'87 4Runner turbo w/3in turbo back exh, 3in high flow cat, hooker turbo 3in 
'84 Urq - formerly with 3in turbo back scorpion (dual muffler) w// 3in high 
flow cat
'83 Urq - stock rear and cat, flowmaster 2.5in center muffler
'85 FJ1387 - SS headers, supertrapp exhaust w 8 plates ;)