Since the benefit of w/m injection seems to pop up every now and then and some post point out that its benefial to run the injection even without tune and you see gains and hardly is the speak of losses. I my self found the only "losses" and the same pattern seems to happen in many other cars as well, as long as the "ecu" does not alter the tune after the addition of W/M. This can happen if the ECU holds back timing, dumps fuel etc due to knock and does not do this with w/m on, then you can see gains even with the same tune. This was the case in my friends RS4 which did only run on normal maps during winter when it was cool, close to 32F, but as soon as it heated up timing retard around 5deg in all runs no matter short or long.
Most resent "case" to my list "negative gain" is my friends dyno runs.
curves which are higher are without W/M activated (values from wheel)
http://www.stcf.net/viggen/dyno_w.jpg
and the timing/boost (runs plenty of both)
http://www.stcf.net/viggen/dyno_w1.gif
Due to short time on rollers this time, the tuning for W/M was skipped
My car, never did dyno it but from acceleration curves the same can be seen, i.e. loss of power through out the power band with w/m active and same tune
http://www.stcf.net/viggen/meth2.gif
rest of the topic regarding this graph can be found here
http://www.saablink.net/forum/showthread.php?t=27581&highlight=water&page=4
and from snow's forum there is this case, same story
http://www.snowperformance.net/forum/viewtopic.php?t=699
Tuning for w/m on the other hand will lead to succes, but the point was to keep this in mind rather than to assume that just by adding the w/m results will follow automatically.
Most resent "case" to my list "negative gain" is my friends dyno runs.
curves which are higher are without W/M activated (values from wheel)
http://www.stcf.net/viggen/dyno_w.jpg
and the timing/boost (runs plenty of both)
http://www.stcf.net/viggen/dyno_w1.gif
Due to short time on rollers this time, the tuning for W/M was skipped
My car, never did dyno it but from acceleration curves the same can be seen, i.e. loss of power through out the power band with w/m active and same tune
http://www.stcf.net/viggen/meth2.gif
rest of the topic regarding this graph can be found here
http://www.saablink.net/forum/showthread.php?t=27581&highlight=water&page=4
and from snow's forum there is this case, same story
http://www.snowperformance.net/forum/viewtopic.php?t=699
Tuning for w/m on the other hand will lead to succes, but the point was to keep this in mind rather than to assume that just by adding the w/m results will follow automatically.