[torsen] RE: RS2 turbocharger

[David Eaton]

i used the 6th gear times for illustration, as the engine speeds are slower
and more illustrative of the lethargy of the rs2, which was the discussion
point.

however, if you look at the 3rd gear times, where the engine speeds are
inevitably faster, the effects are the same, i.e. k24 beats rs2, but the
deltas are different.  particularly interesting in these data are the
performance of the 2 cars in the 2,700 to 3,800 rpm range, where most would
assume that the rs2 would have ascendancy.  not according to these figures -
the k24 is still comprehensively faster.  this, once again, ime, is
indicative of the lethargy of the rs2 below about 3,200rpm.

mph     rs2    s2     rpm range        outcome
20-40  5.7    3.8  (1515 to 3030)  rs2 22% slower
30-50  3.2    2.9  (2723 to 3788)  rs2 27% slower
40-60  2.8    2.9  (3030 to 4545)  rs2 14% slower
50-70  3.6    3.8  (3788 to 5303)  rs2  5% faster

dave
'95 rs2
'90 ur-q
		-----Original Message-----
		From:	Bernard Littau
[mailto:bernardl at acumenassociates.com]
		Sent:	Friday, 14 June 2002 9:24 a.m.
		To:	David Eaton; 'Quattro List'
		Cc:	torsen at audifans.com
		Subject:	RE: [torsen] RE: RS2 turbocharger

		Hi Dave,

		You wrote, some time ago, in this debate:

		> 		lets look at the maths from the stopwatch
numbers.  take the
		> k24 aby s2 vs
		> 		the rs2 in top (6th) gear, and the in-gear
increments.  time
		> in seconds, rs2
		> 		1st, then s2.  using the gear ratios
(specifically
		> speed/1000 rpm figures) i
		> 		have derived the engine speed at the mph
range for each car
		> - which is in
		> 		brackets after the time in seconds.
		>
		> 		Mph     rs2    s2     rpm range
outcome
		> 		20-40  14.8  11.1  (813 to 1626)    rs2 33%
slower
		> 		30-50  12.5    8.9  (1220 to 2033)  rs2 40%
slower
		> 		40-60  10.2    7.0  (1626 to 2439)  rs2 46%
slower
		> 		50-70   7.7     6.1  (2033 to 2846)  rs2 26%
slower
		> 		60-80   6.0     6.4  (2439 to 3252)  rs2
6% faster
		> 		70-90   6.1     6.8  (2846 to 3659)  rs2 10%
faster
		>

		This assumes both cars are trying equally hard.  One would
need to know that
		neither car is somehow retarding the ignition or otherwise
trying to
		compensate for a pretty low rpm with high throttle
situation.  You are
		really in the engine lugging area, and lifting the head
gasket can be an
		issue.  It's possible the factory added code to protect the
engine to the
		engine management system, or that the knock recovery
algorithms are
		different.

		I know that in some more modern drive by wire cars (Saab),
even the throttle
		plate is not fully open in these kinds of situations.

		Someone really needs to try both an RS2 turbo and a K24
turbo in the same
		car, back to back.

		Just food for thought.  Anyone know the reality of what the
motronic does in
		these situations on the various cars?

		Best,

		Bernard Littau
		Woodinville, WA
		'88 5ktq (RS2)