[urq] RS2 vs. k24-young punk weighs in

[Archibald, Jon]

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Scott,
I agree completely with your statements, but I would like to note that the
situations you describe where the RS2 forges ahead involve drivers who
really know how to get power out of a car (I will assume you fit into this
group) and situations where the car is kept in high rpm bands. Under more
normal driving conditions, such as accelerating in 3rd gear from say, 2500
rpm to 4500 rpm, by the time the RS2-equipped car hits its stride, I would
wager the k24-equipped vehicle (assuming turbo the only variable) would
already be a car-length ahead. I think 90% of minor street "confrontations"
like this are over after one gear, so I imagine heat soak isn't even a
factor. On a track day or a situation where two drivers are really winding
their cars out, RS2 will prevail. My theory on your RS2 t44 beating your k24
urq is that if you really have raced them off the line, you have gotten the
revs in the wagon up to at least 3-3.5k before dropping the hammer, putting
the RS2 close to its sweet spot. In a 2500-4500 rpm "race" from a rolling
start, I'd put my money on the k24 urq. On the street, I still have to say
the k24 is the best solution 95% of the time for 95% of people. On the track
and/or with shorter gears and more aggressive driving style, the RS2 or even
for that matter the k26 will prevail if kept spinning. I love my RS2 in my
20vt urq with short gears, but I would not choose it over the k24 in a 10vt
car unless it saw a lot of track use.

Jon Archibald


-----Original Message-----
From: QSHIPQ at aol.com [mailto:QSHIPQ at aol.com]
Sent: Wednesday, June 12, 2002 10:55 AM
To: JArchibald at whpacific.com
Cc: urq at audifans.com; quattro at audifans.com; torsen at audifans.com
Subject: Re: [urq] RS2 vs. k24-young punk weighs in


Jon, I'd take btdt over theory anyday.  That said, I've got the RS2 sitting
in my CIS wagon, and it works with minimal lag.  I've got the k24 in the WX
urq, and it works with minimal lag.  What most would expect to see
(including
me) is the k24 taking my wagon off the line (especially since these are 10vt

applications).  That just doesn't happen.

What the MAPS indicate is that a turbo can have more inertial mass, and
still
give the same "output".  The RS2 *can* be slower, and still provide the
power.  AND since it has more inertial mass, the RS2 turbo in chassis
APPLICATION will be much more sensitive to how those applications (and their

mass) affect spoolup of the turbocharger unit.

The k24 unit on the other hand, heat soaks quickly.  Once it does, it's
"edge" (quick spoolup, great output) becomes compromised in a HUGE way.  And

that heat soak will overwhelm the IC, the turbo outlet temps, and many
times,
the cooling systems of the cars themselves.  BTDT.

Bob Dupree and I have both driven the Group A S2 rally car from MTM many
times.  We know the engine is the same (ADU).  We know the turbo is RS2k26
based.  And we know that the difference between coast/vacuum and WOT/FULL
boost is nothing short of phenom.   Which leads me to believe that the
benefits of the RS2 turbocharger are really high.  And many of us with them,

haven't found the right combination of ancillaries yet.  Or maybe just can't

afford them (that flywheel/clutch assbly is really light).

SJ