RE: [S4 (C4)] Hoppen, IA, TAP, MTM, Wetterauer: power + torque

["Geoff Jenkins" <jenkinsg@pilot.msu.edu>]

> Which mod to the 1993-1995 S4 gives the best results?
>
[SNIP]
>
>    1. Anyone gone shopping for mods for the S4 perhaps
>       provide me with some info on what they found out
>       to be the "best"?
[SNIP]

I've driven the following setups:

i) Stock
ii) TAP chip, K&N, Scorpion exhaust
iii) Hoppen (MTM) chip, RS2 manifold, Abt exhaust
iv) TAP chip, hybrid (big) turbo (don't know which), Scorpion exhaust

Differences (very much IMHO):
-----------------------------
Boost RPM:
i) Stock comes on at about 2500+
ii),iii) TAP & Hoppen chips come on at about 3000, but the Hoppen comes on
more gradually, not a big "thump" of torque at 3000 (which is what the TAP
chip gives)
iv) Big turbo came on later, maybe 3500rpm, and was even less subtle than
the TAP chip (also, _seemed_ worse off-boost)

Power gain:
i) N/A
ii)/iii) Pretty equivalent performance from the TAP and Hoppen setups, with
a slight head to Hoppen ('cos of the manifold?)
iii) Lots of power on boost, bugger all off boost

Driveability:
i) Probably the easiest is the stock motor. It seems to have the lowest
on-boost RPMs, and a very smooth boost process
ii) TAP's chip delivers such a wad of torque at about 3000rpm that you end
up waiting for the tach to hit 3k. Not good for stoplight GPs (I don't like
launching from rest at 3k), but good on the freeway
iii) More driveable than the TAP setup, just because of the smoother
progression onto boost
iv) Not my idea of subtle, nor easy to hustle around town

Frank Amoroso should be able to tell us all what the RS2 turbo adds to all
this. Based on the evidence of the TAP and Hoppen sets I've seen and driven,
I think I'd go with the RS2 mods over the TAP setup.

Minor note: The exhausts that come with the Hoppen and TAP setups are both
louder than the stock muffler, but they have different characters. The TAP
(Scorpion) exhaust is quieter than the Hoppen (Abt) one (which is very boomy
at low revs), but the Hoppen one sounds better at high revs, where the TAP
one becomes raspy and "Boy-Racer"-ish

HTH,

Geoff