[BiturboS4] RE: Hesitation....and now...Catbacks

Edwards, Dave Dave_Edwards at iOra.com
Fri Oct 25 10:00:01 EDT 2002

Well thank you for such confidence in my posts. I admit I do have a tendency
to write BS on some subjects :-) but never on technical issues.

Yes I do have dyno plots of the various stages of modification of my car.
However my assertion is not based on these (my first mod was chip and
cat-back at the same time), but on what my tuner has done. They have fitted
Miltek cat-backs to all the Audi turbo cars and have the dyno results. In
general the amount of extra hp and torque they have seen from cat-back only
is in single figures.

You can expect a further 30hp/30lbft from the Miltek cats, but the chip will
really need to increase the fuelling slightly to get this. Again this is
based on a before and after dyno.

Maybe there's something about the US cars that gives more performance gain
from the cat-back only. If so I look forward to reading about those dyno


-----Original Message-----
From: jysap at cs.com [mailto:jysap at cs.com]
Sent: 25 October 2002 02:14
To: Dave_Edwards at iOra.com; biturbos4 at audifans.com
Subject: RE: [BiturboS4] RE: Hesitation....and now...Catbacks


Can u expand on your point:

>This should not be much of
>a problem with the cat-back (which IMO just changes the noise, not much

Have u done a dyno of an S4 with a stock exhaust vs. catback vs. no-cat
exhaust (under the same conditions)to get a basis for your statement?
Without making such a comparison, I couldn't see how u could render such an
opinion. Maybe you (or someone else) has and could pass such info to the
list, as a public service announcement.

Y2K S4
86 951

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