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Discussion Starter · #1 · (Edited)
Hello,

I have written earlier about the failed exhaust valve on the TXSS, after a short log run and 3 WOTs for a Vtune. Brian states he has never seen so hot Inlet Air Temps (IATs) and that might have caused detonation. The climate here is very hot in summer, though I would have thought Saab/GM would have tested the engine setup in even more extreme environments...??? :confused:

So, Brian has suggested a solution to lower the IATs far more than an IC would do, by this system:
http://www.snowperformance.net/stage-2-gm-maf-boost-cooler.html

In theory it sounds like a great idea, especially considering we never use the washer fluid for anything useful, anyways. I have after weeks of searching found a local provider of methanol.

So, has anyone seen, heard or expernced someting similar to this on a V6 2.8T?

Any informtion shared would be appreciated.

Thanks,
tSS
 

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Next on my list too -- and then call it a day (how many times have I said that :lol:).

Not much space under the hood so washer fluid reservoir will have to do (with new pump/fittings a la SnowPerf/equivalent). Or to trunk.

In reverse, the meth/water combination optimal for injection (roughly 50%/50%) is sufficient as a washer fluid and I'm presuming one need not sacrifice that function (though might be going through rather alot, expensive too, when you're walking and chewing gum!).

BTW: Still think there's merit to a hood vent where turbo is...
 

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this list is a few years old now, but a wwaf mix provided its got meth in it and is good for -40 etc will work. I dont use meth anymore; the gains are big but the pita of filling the tank etc especially on the track, road racing consumed so much , I needed about 3 gallons for a 20 lap session. Not on a SAAB.

 

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Rodney at AIS.com does this kick *** 3 gallon tank with moulded provision in the base for the pump, it trunk mounts and makes a very good solution for a meth injected setup
 

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Next on my list too -- and then call it a day (how many times have I said that :lol:). BTW: Still think there's merit to a hood vent where turbo is...
NTP - Famous last words indeed on the mod side. :roll: Certainly never works out for me that way either ........

SS - Our driving conditions during summer are pretty brutal as well. I only started logging IATs in the past few months which has been our winter. Removing the cat from the DP has helped to lower my under bonnet temps. Await with interest the outcomes of your water/meth route.
 

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With all of that you may as well mount your battery back there for better balance or perhaps that is where the methanol tank could go? A few posters had switched the battery to the rear. Make sure the area is vented, I believe they used the spare tire well.
 

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Wait what?

I searched this literally 4 days ago
and the information that I retrieved (from these same forums) was that the knock sensors would detect the meth as knock which then retards the timing.

This is confusing.
 

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positioning the nozzle and the tune is critical. sometimes some forum stuff is simply retarded.
This post has been revived dates back to 2008 or earlier , very well written.

taken from another thread by bill shurvington(ausrotary)

K Stage 1

Intro: This has been covered before, but just to set the scene. Water is NOT passive in combustion, it aids the

conversion of CO to CO2, which is where most of the energy of combustion is released. It also helps cool

things down( in the process reducing the work done in the compression stroke) and prevents detonation.

You can replace a significant amount of the fuel with water allowing you to run at the best power AFR rather

than running overly rich and losing power. Disclaimer: I give not a stuff what is said on WI equipment vendors websites, so if I disagree with aquamist so be it. They are a pump manufacturer.

Pre-turbo WI: Compression in a turbo is usually adiabatic. This means that the air is heated as it is

compressed, which takes power from the shaft and requires removing through an intercooler. If you inject

water before the turbo, then you can move compression to near isothermal, so very little heat is added, and

less power is taken from the turbine to compress the air for the same boost level. You can loose the

intercooler and therefore suffer less pressure drop between compressor and inlet. All of which gives you the possibility to get more power out the same turbo.

Water has a very high latent heat of vapourisation, but once you have reached the saturation pressure in air, then you gain no more cooling at that point. However Dalton's law comes to the rescue at this point and if you bung in some other miscible fluids, say methanol and acetone, then each has its own saturation pressure, and you get an accumulative cooling effect. A little petrol would do the job if you added a second injector for it.

And here we hit the first problem. You need fine atomisation to avoid potential blade damage. For this you need an airshrouded injector, such as VW used in some of their CIS systems (hunting applications list for those). RX7s have an airpump that can be turned to this application. Other option is to weld a bung into the scroll as most of the compression happens here.

I need to run some numbers on exactly the effect of various fluids here, but imagine if you had cut the power needed to get the PSI wanted by a 1/3. You would get spool up at 2/3 of the gas flow before and could run at higher boost once you had spooled.

Post turbo WI: Here you are adding water to deal with combustion and detonation reduction. Ideally you would inject directly into the chambers to minimise any charge displacement. The OMP drilling in the housing would work nicely for this if you run premix. In terms of sizing you would be wanting to replace about 30% of the fuel with water, so size accordingly.

Quick note on A/R changes with WI: If you inject water directly into the exhaust, then it rapidly expands and turns to steam. In doing so it takes heat out of the exhasust, but the volume gain more than makes up for this. Tricky to implement, but can be used to change the effective A/R of the turbine, giving you a much wider operating range. MSD do a system for 2 strokes that uses this effect to change the effective tuned length of the exhaust to improve scavenging.

That's me out of time for now, but have a think and ask some questions. Remember, if you say 'but Mazda/aquamist/the lad with a supra on my block don't do it this way' I shall laugh maniacally and point you to the work of Sir Harry Ricardo on the rolls royce merlin engine in the late 30's. He was a genius.

Part 2b: water is good for your bang

below is a great mail written by Bob Harris a few years back explaining, in far more lucid prose than I could ever hope for. Key points to note in the text:

1. Water speeds up the key reactions releasing energy to the crank in a sharper peak. This means more power at the wheels. Note the comment that 2/3 of the energy released in combustion comes late in the cycle without water present at the beginning. This is less of a problem in a rotary than a piston, but you still lose leverage on the eccentric (note I haven't looked at it from a heat lost to the rotor perspective).

2. Water injection has been shown to give very significant increases in max power

3. At >35% WI it has been shown you can run under boost all the way back to stoich without detonation in piston engines. No reason a rotary shouldn't be similar. Extrapolating this you can see that you can also run more advance (more power) and also use AFR to control power output, rather than run stupidly rich just to prevent engine death, or backing off the spark so you loose lots of the HP you paid for.


Quote:

Let us take a quick look at ignition. Those who have a Heywood can look it up
- mines on loan so going by memory. The first thing that happens is a plasma
cloud is formed by the arc consisting of super heated electron stripped atoms.
When this cloud "explodes" a ball of high energy particles is shot outward.

The highest energy particles are the hydrogen atoms - and they penetrate the
charge about 5 times as far as the rest of the particles. As they lose energy
and return to normal temps - about 5000 k - they begin to react chemically
with any surrounding fuel and oxygen particles. The effectiveness of spark
ignition is directly related to the availability of free hydrogen. Molecules
containing tightly bound hydrogen such as methanol, nitromethane, and methane
are far more difficult to ignite than those with less bonds.

During combustion - water - H2O ( present and formed ) is extremely active in
the oxidation of the hydrocarbon. The predominate reaction is the following:

OH + H ==> H2O
H2O + O ==> H2O2
H2O2 ==> OH + OH
Loop to top and repeat.

The OH radical is the most effective at stripping hydrogen from the HC
molecule in most ranges of combustion temperature.

Another predominate process is the HOO radical. It is more active at lower
temperatures and is competitive with the H2O2 at higher temps.

OO + H ==> HOO
HOO + H ==> H2O2
H2O2 ==> OH + OH

This mechanism is very active at both stripping hydrogen from the HC and for
getting O2 into usable combustion reactions.

Next consider the combustion of CO. Virtually no C ==> CO2. Its a two step
process. C+O ==> CO. CO virtually drops out of early mid combustion as the O
H reactions are significantly faster and effectively compete for the available
oxygen.

Then consider that pure CO and pure O2 burns very slowly if at all. Virtually
the only mechanism to complete the oxidization ( Glassman - Combustion Third
Edition ) of CO ==> CO2 is the "water method".

CO + OH ==> CO2 + H
H + OH ==> H20
H2O + O ==> H2O2
H2O2 ==> OH + OH
goto to top and repeat.

This simple reaction accounts for 99% + of the conversion of CO to CO2. It is
important in that fully two thirds of the energy of carbon combustion is
released in the CO ==> CO2 process and that this process occurs slow and late
in the combustion of the fuel. Excess water can and does speed this
conversion - by actively entering into the conversion process thru the above
mechanism.

The peak flame temperature is determined by three factors alone - the energy
present and released, the total atomic mass, and the atomic ratio - commonly
called CHON for Carbon, Hydrogen, Oxygen, and Nitrogen. The chemical
reactions in combustion leading to peak temperature are supremely indifferent
to pressure. The temperatures and rates of normal IC combustion are
sufficient to cause most of the fuel and water present to be dissociated and
enter into the flame.

As can be seen above, water is most definitily not only not inert but is a
very active and important player in the combustion of hydrocarbon fuel.
Ricardo and others have documented that under certain conditions ( normally
supercharged ) water can replace fuel up to about 50% and develop the same
power output, or that the power output can be increased by up to 50% addition
of water. This conditions were investigated by NACA and others for piston
aircraft engines. It is important to note that these improvements came at the
upper end of the power range where sufficient fuel and air was available to
have an excess of energy that could not be converted to usable pressure in a
timely manner.

As a side note - Volvo recently released some SAE papers documenting the use
of cooled EGR to both reduce detonation and return to a stoic mixture under
boost in the 15 psi range - while maintaining approximately the same power
output. Notice - they reduced fuel and still get the same power output.

When you consider that EGR consists primarily of nitrogen, CO2, and water ( to
the tune of about two gallons formed from each gallon of water burned ), you
might draw the conclusion that it also was not "inert". They peaked their
tests at about 18% cooled EGR - which would work out to about 36% water
injection and got about the same results under similar conditions that the
early NACA research got.
 

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Ive been running it pre throttle body for the past 8 months and its amazing. Im using a Snow performance stage 2 MAF based progressive system, with the washer tank used for the reservoir, and the pump now mounted upside down on the front crash support. What you really need to make sure of is that there are NO leaks in the charge piping as that will throw everything out of whack. There is a gain to be had even without tuning (as I am running it now) becaue this car is always in closed loop fueling (fueling is controlled by a wideband afr sensor). This means it automatically pulls fuel when the mixture is richened. My results were 4/10ths and 4mph improvement in the 1/8th mile. Injection time is definitely noticable because the power delivery smooths out, and you feel a slight increase in power. I'm sure there are more gains to be had when tuning for it, but for now I just use it as a cooler/octane booster for the normal tune.
 

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" Im using a Snow performance stage 2 MAF based progressive system, with the washer tank used for the reservoir, and the pump now mounted upside down on the front crash support."

Well described and I'm learning much in this thread beyond the Manufacturers FAQ -- Brian [VTuner] turned me on to Snow Performance.

Obliged if you're able to provide a picture(s) of your setup.
 

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" Im using a Snow performance stage 2 MAF based progressive system, with the washer tank used for the reservoir, and the pump now mounted upside down on the front crash support."

Well described and I'm learning much in this thread beyond the Manufacturers FAQ -- Brian [VTuner] turned me on to Snow Performance.

Obliged if you're able to provide a picture(s) of your setup.
If I remember, I'll snap some the next time I have the bumper off.
 

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Discussion Starter · #14 ·
Mix mpg?

Ive been running it pre throttle body for the past 8 months and its amazing. Im using a Snow performance stage 2 MAF based progressive system, with the washer tank used for the reservoir, and the pump now mounted upside down on the front crash support. What you really need to make sure of is that there are NO leaks in the charge piping as that will throw everything out of whack. There is a gain to be had even without tuning (as I am running it now) becaue this car is always in closed loop fueling (fueling is controlled by a wideband afr sensor). This means it automatically pulls fuel when the mixture is richened. My results were 4/10ths and 4mph improvement in the 1/8th mile. Injection time is definitely noticable because the power delivery smooths out, and you feel a slight increase in power. I'm sure there are more gains to be had when tuning for it, but for now I just use it as a cooler/octane booster for the normal tune.
I've been unable to find how often you'll have to refill the fluid mix in normal conditions. Any data recorded, Titan?
I understand the water injector is progressive and will not be used at idle and lower rpms/MAF pressures, ie constant speed?
Basically, is it more or less often than your gas refill, considering the washer fluid tank is 6 Liters?
Can I go on a road trip without a spare mix container .

Really need to know this before taking the plunge....
Range anxiety, maybe?! ;)
Thanks.
 

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I've been unable to find how often you'll have to refill the fluid mix in normal conditions. Any data recorded, Titan?
I understand the water injector is progressive and will not be used at idle and lower rpms/MAF pressures, ie constant speed?
Basically, is it more or less often than your gas refill, considering the washer fluid tank is 6 Liters?
Can I go on a road trip without a spare mix container .

Really need to know this before taking the plunge....
Range anxiety, maybe?! ;)
Thanks.
Normal driving you do not use high boost that much, and that is when it is prudent to use the meth/water injection. If you do run out, tailor your right foot and you will be fine. Knowing the new 9-3ss I assume there is an idiot light that lights up the SID when you run low on washer fluid. I check mine visually, and top off. I treat it like engine oil level.
I have 2 cars with meth/water injection. '78 99t with a very crude strategy where a pump is activated when a pressure switch reaches a set threshold. This is an Aquamist system from 20 years ago.
My second setup is for my '89 900c. I use my standalone engine management to drive the pump and a quick acting valve to control the delivery amount.
The pump is energized at 75kPa engine load (12 psi boost). The quick acting valve gets a pulse width modulation (pwm) input based upon engine speed. This is similar the fuel injection pwm.
Short answer I fill up my windshield maybe once per 10 fuel fill up on a daily driving mission. A track day is on the other extreme. Might use a full bottle for driving hard getting 11 mpg. Both cars are 2.0 liter cars, so a 2.8 all things being equal, will consume more.
 

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Discussion Starter · #16 ·
Great info!
As long as I can expect to run a few gas tanks between refills of water/methanol I'm good.
Thanks Sq!
 

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practically speaking on a 2.0 s/c ecotec, two to three weeks on the street with a 10 psi pressure switch and 10-15 laps at the road race track with a 3 gallon tank.
Pay attention to the wwaf chart; 50/50 meth/water mix is what works best. 7 gph nozzle. Fancy progressive controllers are okay if you want to play a lot with the tune. Aquamist flow indicators are a pita as they are metric 4mm . But the lines and connectors most available are 1/4 thats class tractor/trailer air line stuff cheap and freely available.

AEM have some really good flow meters now that do a whole lot more than just monitor flow; remember you need a one way valve right at the nozzle to stop unwanted meth mixture trickling in. Pre throttle body post MAF makes the most sense to me but the articles I quoted are a lot more sophisticated.
 

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I could probably improve the performance of the engine if i fine tune the controller... If I am driving a normal commute, it will last up to a month. The controller commands a 10% duty cycle at 2500 rpm at full throttle (A little less than 3v from the maf sensor). Under normal street driving and steady state driving, there is no injection. At that point, distilled water will work for the charge cooling in a pinch until you get to more methanol.
 
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