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About W/M injection

1K views 12 replies 4 participants last post by  JZW 
#1 ·
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.
 
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#2 · (Edited)
How many times we going to go through this? Its been beatin into the ground now over and over. We have discussed undersized ic's and the benifit or an aggressive staged tune, we know they are out there and they would probably benifit, the ones you names as over sw the hw, in those cases, I would venture to say there are gains to be had.

No question the best way to get the most out of the system is to one, size the w/m flow correctly for the engine set-up and power and tune the timing and a/f correctl

If a tune is on the lean side and marginal on ic, more will be gained.

My car richened up a good 1/2 a point, so if the tune was at 11.5/1 and you put w/m on it, yea, 11.0 would show a loss in torque and power.

I have said this many times. 50% of the increase comes from a colder denser air charge and 50% comes from being able to advance the timing. That said, if the current ic is great or adequate, minimal gains will be seen on the first 50%. The second half should also include air fuel mixture, if its a concervative tune with the a/f already way rich to try and cool the combustion chamber, then yea, making even richer with w/m is going to hurt performance.

But, if its a stage 4 and the injectors are maxed out and the turbo is maxed out and the ic is maxed out and the tune is as you say with the sw overdone on the hw, then more gains from a w/m injection system would be yielded.

Making a blanket statement w/m will not help without a tune cannot be made as there are many different tunes and levels of hw out there and many cars are on the edge and would benifit from w/m. There are cars with concervative tunes as well and those would not benifit from w/m in many cases.

Then there is a whole other part of the equation, that is the longevity of a w/m system in racing or many long pulls, the chemical ic does not heat-soak! Does not get worse in slow moving traffic and there is the side-benifits of a clean head! There is no doubt a cleaner combustion chamber is less likely to knock than a carbon filled one.

We have been all through this many times, no need to keep beating up this horse:cool:

John
 
#4 ·
We have been all through this many times, no need to keep beating up this horse:cool:

John
nope the idea of this thread was to "beat" this horse with something else than the feeling of the rear, ie. to gather together results which have been measured in real life and not just the usual feeling based talk. Sorry for my bold statement, but as we know many people do "find" gains from parts that dont even give gain, usually becuase the benifit has taken for granted even before the install or based on hear say what worked for somebody else in a completely different solution. Before I bought the w/m kit I tried to search for this type of data/ measurements but thus all the talk around the issue there really isnt much concrete stuff out there. So yes I wanted to see it out for my self what I got, so I tested both the none tune and tuned for it and as said gains negative, but the positive.

Now adays when T5suite is out and it has a "built" in logger studying these issue should not be that diffucult so others can benifit from others tries and helps to understand what else needs to be done besides the physical installation and what is the expectatation if only the physical installation is made. Tossing statetems 50% gains from this and that if or else but bla bla may apply for "something" and may be just the opposite in "something" else and as I see it the 50%/50% rule is directly from the kit supplier marketing material without the IF's and BUT's.
 
#3 ·
"But, if its a stage 4 and the injectors are maxed out and the turbo is maxed out and the ic is maxed out and the tune is as you say with the sw overdone on the hw, then more gains from a w/m injection system would be yielded."

i should have numbers to prove this in the coming months. when i do get them, i'll post them up here along with the dyno graphs. :)
 
#5 ·
Real life is great, its just if the real life is a car with a great ic and rich mixture, no gains would be had, losses most likely.

So, if you are going to give real life cars as an example, how about taking some of the ones that are on the edge, like a stage 4 with tdo4 and maxed out turbo/injectors, etc and see what the real life data shows for a car like that.

My own car was one of these maxed out boys with t28 and it showed gains with no other sw changes.

There needs to be more than one car to see the whole picture and demonstrate what I have said about appying w/m to a car is going to be directly related to how hard that cars hw is being pushed and how hard the sw is being pushed.

John
 
#6 ·
as usual this topic as others is not "locked" one is free to put forward what ever they wish...
so if you have the examples lets see them... I tossed a few which I have run a cross and seen my self.

and yes I do run with a maxed out turbo, but IC was taken care of a long time ago.
 
#7 · (Edited)
I have many times, my dyno sheets showing a 39wtrq gain with no other sw changes.

The larger turbo helps too, need to see some examples with a small t25 or tdo4 or big t28 like mine. Also, my test have always been at elevation, maybe this shows more gains since we are at a disadvantage with 15% less efficient ic's and harder working turbo, etc.

John
 
#10 ·
It was over 2 years ago and that is a typo if that is really mine.

The first one was no sw changes, w/m injection, was on different days, so its hard to say what it all really meant. In sae it showed 39wtrq gains.

Little to no hp peak gains.

John
 
#13 ·
Yea, I know what you are saying and feel in many tunes that is correct, but also feel there are many tunes that are aggressive and on the edge and I think those tunes would benifit from w/m injection.

Best way is to tune for it, no question.

John
 
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