RS2 Turbos

[JShadzi at aol.com]

Right, I guess I should have put quotes around K24 in my original post, but I
think my follow up post summed it up nicely, you might not have seen it:

Definitely not K27, it is made up of parts of the K24/26, but Audi left the
K24 designation on the name plate...see Scott's Justosons quote as per
www.urs4.com:

<<
  The RS2 is all K26 turbo.  I've had a couple dozen of RS2 and RS2 
Competition turbos apart in the past 6 years.  The hot side is based on the
smallest of the K26 series housings, with a Porsche spec'd hot side wheel,
and the appropriate milling of the housing (which results in a slightly
larger downpipe opening).  The center section is stock Audi K26 WC, and the
cold side is a K24 cold side housing with a K26 cold side wheel.  The
RS2/Comp both use the larger K26 shaft for the wheels.  The RS2 Competition 
uses a larger cold side wheel and housing, the hot side stays per early RS2. 
What throws most folks off, is that KKK left the K24 designation in their
part numbers on the cold side tag.

The actual answer to the years of the K24 cars in the US is up for some
discussion.  The audi "claim" is that as of 1989.5 (late MC dual knock
MAC-14) Audi switched to the K24 turbo on all I5 turbo applications.  This
switch also "supposedly" came with a revised cam profile, flat flywheel (+
different TOB fork), and 2pc exhaust manifold.  IME, 1990 was the bastard
year for previous year pieces parts.  I've seen 1990's with single pc
exhaust, K26 turbos (but all have had the flat flywheel and the revised cam
profile).

As of 1991 + intro of the 20vt cars worldwide, all Audi 20vt (I5 only -
thought I'd miss that:) turbo cars except for the RS2, were K24 based
turbochargers. 

Maximum boost to the K24 is altitude corrected at 16psi.  At 3200ft the 1991>
stock 20vt cars lowered maximum boost threshold to prevent overspin of the
turbo.  You guys with modded 20vt computers with K24 turbos should reread
that last sentence.

Scott Justusson
QSHIPQ Performance Tuning
>>

So, it would be an easy mistake to make, if you'd ever seen an RS2 turbo, you
might have done the same...

Javad>>>>>>>>>


<< Not to bust your b*lls Javad, but looking at the post you put up:
 >>Well, that would be an easy mistake to make, since the RS2 really IS
a*modified* >>K24.Javad

 you made one of the classic errors in the interpretation of the RS2 turbo.
The k24 cold side housing is the only k24 part on that turbo (most likely
used  for the parts bin turbo inlet hose size/app).  Which means your
statement "the RS2 really IS a *modified* k24" per your post, isn't at all
correct.  Not to worry, many q "experts" (including a few tuners)
thought/think the same.  Run the part numbers on the center bearing housing
is all that is needed, k26 stampings (k24 parts don't fit the k26 CB)

 SJ >>