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Pre-compressor methanol injection

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A agree, and disagree.

Yes water may be able to dissipate more heat. But it has other flaws that make using it impractical.


Because of it's high density and zero flash point, you can't run as much water through compressor as you can meth. So while lb for lb water will cool more efficiently, you can't use as much of it to cool.

Getting the water droplets down to a manageable size is impractical when compared to methanol.


It's not combustible. So you are filling up your cylinders with space that could be occupied by air or fuel.

Up to a point I suppose your right... but for a practical everyday use meth is far superior in every way IMO. I've tried both on my cars. From what I've seen, 100% meth always out performs 50/50 or straight.

I was only talking about wet compression (pre compressor). Cooling the air as it passes into and part way through the compressor is not what wet injection is about. It is about the sudden transformation of liquid to gas at the blade tips. Water and methanol both flash (explosively) at about the ends of the blade just before the air cascades into the compressor volute. Since both flash instantly at the point neccesary, the chemical that absorbes the most heat in the proccess is the most beneficial.

If water were injected properly (right at the compressor nut), then all is fine with droplet size with typical water injection kit pressures. Folks report being concerned of of compressor damage; but when injecting right on the hub, there's been practically no reports of actual compressor damage due to the injection.

Now post compressor there's lots of differing opinions. But all commonly agree: the more meth the better.
 
I guess that kind of music is suppose to appeal to the dopers. Nutramist systems are used to grow hydroponic pot!
Hey now, that song is a classic! One of the best techno songs of the mid-90's.

Getting higher pressure will help but we are starting to hit the max that other components can handle. Would have to go over to AN style stuff if we went up to 400psi.
Hey Chance, what kind of deal can you give me on your 250 psi pump for our test? :sneaky: PM me if you get a minute.
 
Chance since you brought it up, do you guys offer an AN line kit, I thought you did but it was custom etc?

99 Racer, what's the test again, this threads been kind of all over the map?
 
Tyler from Street & Strip (a fellow DSMer) and myself will be doing a test on an engine dyno. He's got a 2.3L ford engine with an HX-35. We're going to be testing precompressor injection using various nozzle sizes and mixtures. We'll be datalogging before and after AIT and HP changes. The engine is on and ready to go. We just need a high prerssure pump and we'll be all set. And of course, we'll publish our test results.


Then, I'll use our results and determine the specifics of the injection set-up for my compound set-up.
 
I was only talking about wet compression (pre compressor). Cooling the air as it passes into and part way through the compressor is not what wet injection is about. It is about the sudden transformation of liquid to gas at the blade tips. Water and methanol both flash (explosively) at about the ends of the blade just before the air cascades into the compressor volute. Since both flash instantly at the point neccesary, the chemical that absorbes the most heat in the proccess is the most beneficial.

If water were injected properly (right at the compressor nut), then all is fine with droplet size with typical water injection kit pressures. Folks report being concerned of of compressor damage; but when injecting right on the hub, there's been practically no reports of actual compressor damage due to the injection.

Now post compressor there's lots of differing opinions. But all commonly agree: the more meth the better.

Alright so post injection aside....

I'm a little confused by the verbiage here...

The flash point of any liquid is the lowest temperature at which a liquid hydrocarbon gives off enough vapor to form an explosive mixture with air.

So how is water flashing?

I think we are talking about latent heat of vaporization here. Defined as the amount of heat required to convert unit mass of a liquid into the vapor without a change in temperature.

Fluids - Latent Heat of Evaporation


Vaporization of methanol is 473 btu's

Vaporization of water is 970.4 btu's

water requires a little over twice the energy to break it down. This means we can quickly over saturate the air charge and have an excess of fluid discharging the compressor and entering the engine. This will also cause humid damp air charge that is not as rich with oxygen.

Where as when injecting methanol, it flashes almost instantly leaving no excess fluid saturation discharging the compressor. This allows us to spray more meth than one could with water. While maintaining the dense oxygen rich charge.

Who is to say how much more we can use though.... And if we spray 2.5x as much methanol would methanol cool more effectively than straight water? Would the "wet compression" effect be lost with methanol because of it's instantly flashing tendency?

I honestly don't know.

I think this partly answers my question.... although it doesn't directly relate to pre-turbo injection. It does prove methanol will lower the air temperature more than water.


2800 HP Twin Turbo Engine built with 4 1600cc Injectors pointed into the oncoming air charge at the spot where the 2 pipes merge with the larger single pipe. The engine is a Methanol fueled engine. On the dyno stand during a pull this setup produces frost on the up-pipe right after the injectors. This thing uses 20 injectors! Who needs an intercooler!

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...although who is to say if he used water pre-compressor if the wet compression would have made the turbos more efficient than the frosty air charges? Somehow I doubt it... :hmm:
 
Here is what I got ready to go on. I will log air temps both before and after when I do it and I will do the same when I head back to the dyno.

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The pipe is made from a piece of exhaust pipe that goes from 2.5"-3". The elbows are SS and there is a o-ring to seal the hole. I used washers to take up the slack. Its a DO 1gph nozzle. I still need to get a pump to run water only. This was the easiest and smallest I could make it so there is as little airflow disruption as possible. It is very tight and not easy for a bump to knock it out of position.
 
Here is what I got ready to go on. I will log air temps both before and after when I do it and I will do the same when I head back to the dyno.

The pipe is made from a piece of exhaust pipe that goes from 2.5"-3". The elbows are SS and there is a o-ring to seal the hole. I used washers to take up the slack. Its a DO 1gph nozzle. I still need to get a pump to run water only. This was the easiest and smallest I could make it so there is as little airflow disruption as possible. It is very tight and not easy for a bump to knock it out of position.

Looks good! Wonder how much airflow your blocking though. It's kinda "beefy" :D.

I'd think something like this would be ideal. Although the dual inlets are a little much.

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Alright so post injection aside....

I'm a little confused by the verbiage here...

The flash point of any liquid is the lowest temperature at which a liquid hydrocarbon gives off enough vapor to form an explosive mixture with air.

So how is water flashing?

I think we are talking about latent heat of vaporization here. Defined as the amount of heat required to convert unit mass of a liquid into the vapor without a change in temperature.

Fluids - Latent Heat of Evaporation


Vaporization of methanol is 473 btu's

Vaporization of water is 970.4 btu's

water requires a little over twice the energy to break it down. This means we can quickly over saturate the air charge and have an excess of fluid discharging the compressor and entering the engine. This will also cause humid damp air charge that is not as rich with oxygen.


Where as when injecting methanol, it flashes almost instantly leaving no excess fluid saturation discharging the compressor. This allows us to spray more meth than one could with water. While maintaining the dense oxygen rich charge.

Who is to say how much more we can use though.... And if we spray 2.5x as much methanol would methanol cool more effectively than straight water? Would the "wet compression" effect be lost with methanol because of it's instantly flashing tendency?

I honestly don't know.

I think this partly answers my question.... although it doesn't directly relate to pre-turbo injection. It does prove methanol will lower the air temperature more than water.


2800 HP Twin Turbo Engine built with 4 1600cc Injectors pointed into the oncoming air charge at the spot where the 2 pipes merge with the larger single pipe. The engine is a Methanol fueled engine. On the dyno stand during a pull this setup produces frost on the up-pipe right after the injectors. This thing uses 20 injectors! Who needs an intercooler!


...although who is to say if he used water pre-compressor if the wet compression would have made the turbos more efficient than the frosty air charges? Somehow I doubt it... :hmm:

By "flash" I mean instantly converting from liquid to gas.

Since water removes 2.5 times more heat than methanol and compressor temps at the transition to the volute are over 300 degrees F (both meth and water instantly change states), you will not over saturate. You only use as much water or meth as needed. And since we're using a heat source that instantly converts either liquid to gas, then it comes down to how much more heat is drawn out during the process.

Methanol only cools better than water post compressor because of surface area of the mist (weaker surface tension). But since surface tension of water is not enough to slow the transition from liquid to gas at these higher temps seen at the compressor exducer tips, then there's no need to bother with a fluid that has a lower surface tension, yet only uses 50% of the heat to vaporize.

WRT increased efficiency from preturbo injection vs post turbo injection cooling. . . Those are two different animals. post turbo cooling (aftercooling) can never reduce the amount of exhaust energy required to spin a compressor at a certain rpm to achieve a certain volume flow. Preturbo injection allows less exhaust energy to be required to achieve a boost threshold because less heat is a result from compression Work required = Specific heat X Mass Flow X (Compressor T out - Compressor T in). Lower the Compressor T out, you lower the required energy from the exhaust to generate a certain flow. Thus you achieve a certain compressor rpm earlier in the rev range at a lower exhasut energy, and you shunt more exhaust straight to the tail pipe increasing the overall VE. Post compressor injection drastically cools the aircharge alone. But a more efficiency compressor with post compressor injection is more effective than a less efficient compressor with post compressor injection. Preturbo injection alters the "effective" efficiency of the compressor.
 
A very interesting topic here guys. I did a lot of research on this last year, and haven't gotten a chance to do much work with it because life got in the way.

Some things I would like to throw out there just so we have them in the back of our heads.

first the use of a progressive controller of any kind will be detrimental in this situation. 'Ramping' the pressure from low to high is not a good way of achieving good atomization. while that may be a worth while sacrifice post turbo, specifically because it eases tuning issues, it should not be considered in a pre-turbo application.

When i was designing my system i bought, then threw out my progressive controller. I still wanted some form of a staged injection system, mostly because i run a small turbo and i run it at two different boost levels. My solution was to run a set of hobs switches to trigger two different nozzles at preset points. effectively giving me the correct amount of chemical intercooling at both my street and strip boost levels.

I also am very curious about the Meth Vs water debate.. to sum up what i have heard in this thread, methanol will flash evaporate in the compressor and should have smaller droplet size and thus have less of an impact on the turbine blades. The concern has been raised about methanol's chemical reaction to aluminum.

Water is said to have larger droplet size but because of its greater heat capacity may be able to better cool the charge, also clearly it will react much less (at least chemically) with the turbo.

Because it has been said that Both water and alcohol would 'flash evaporate' It would lead me to believe that water would be the most beneficial as far as total cooling effect when injected pre turbo. as you have said, it has the greater heat capacity, droplet size aside, IF it is completely evaporating in the turbo then water is what you want to cool with. That being said, with droplet size being important in regards to turbo life I would think that we may once again see some form of a water/meth mix being the most beneficial.

In regards to cooling between stages, I would recommend mounting that nozzle as far away from the 2nd turbine inlet as possible. IF the goal is to remove As Much Heat As Possible before the second stage it makes sense to allow the intercooling process the maximum time available. It is not as though the second stage will not benefit from pretubo injection if the mist is given a longer time in suspension.

the finial thought i would like to raise would be that of the nozzle size debate. I think the idea to inject the equivalent of the 14ghp nozzle from a series of smaller nozzles needs to be examined. It occurs to me that in the case of these injection systems we are dealing with a single size of supply tubing. running a single tube at 250psi and then branching that into 4 lines of the same diameter to feed each nozzle will result in a pressure drop. I understand the pump will attempt to compensate but will it be able to keep up with a 4x increase in volume? I cant say one way or the other, just a thought that would keep me up at night. IF it were unable to completely compensate for this then we would have to consider the cost of a pressure drop in regards to atomization. Logically there is a point where injection through a single 14gph nozzle would give you better atomization then 4 smaller nozzles at a lower pressure (aside from the fact you cannot break down 14 into 4 parts neatly). Are we anywhere near that point? I dont know.

as far as mounting pre turbo is concerned, i really disliked the 90* elbow immediately pre-turbo because of its impedance to clean air flow. I went though all this trouble to get nice smooth intercooler and intake bends and i didnt like that i was 'just hanging it out in the wind'. what I did was mount two nozzles pre turbo on opposing sides of the intake pipe, with the mounting bungs cut to come in at roughly a 60* angle the nozzles protruded into the intake slightly and the spray pattern looked good in testing. sadly as i said, i never got the opportunity to try it on my car.


Here's to all of you doing the testing and pushing the envelope!!! I cant wait to see the results.
 
By "flash" I mean instantly converting from liquid to gas.

Since water removes 2.5 times more heat than methanol and compressor temps at the transition to the volute are over 300 degrees F (both meth and water instantly change states), you will not over saturate. You only use as much water or meth as needed. And since we're using a heat source that instantly converts either liquid to gas, then it comes down to how much more heat is drawn out during the process.

Methanol only cools better than water post compressor because of surface area of the mist (weaker surface tension). But since surface tension of water is not enough to slow the transition from liquid to gas at these higher temps seen at the compressor exducer tips, then there's no need to bother with a fluid that has a lower surface tension, yet only uses 50% of the heat to vaporize.

WRT increased efficiency from preturbo injection vs post turbo injection cooling. . . Those are two different animals. post turbo cooling (aftercooling) can never reduce the amount of exhaust energy required to spin a compressor at a certain rpm to achieve a certain volume flow. Preturbo injection allows less exhaust energy to be required to achieve a boost threshold because less heat is a result from compression Work required = Specific heat X Mass Flow X (Compressor T out - Compressor T in). Lower the Compressor T out, you lower the required energy from the exhaust to generate a certain flow. Thus you achieve a certain compressor rpm earlier in the rev range at a lower exhasut energy, and you shunt more exhaust straight to the tail pipe increasing the overall VE. Post compressor injection drastically cools the aircharge alone. But a more efficiency compressor with post compressor injection is more effective than a less efficient compressor with post compressor injection. Preturbo injection alters the "effective" efficiency of the compressor.

Gotcha...

Makes prefect sense. But...

How do you know the tempratures in the compressor scroll are exceding 212*F (boiling temp is vaporizing temp right?) at all times?

I know it's pretty safe to assume the comp. scroll temps are in the mid 300* range on a small turbos (16g's etc) cranking out alot of boost. But once the water injected and starts cooling are you sure temps wouldn't be lowered to sub vaporization levels? I could see water being more effective with compound setup's or any setup generating over the "norm" heat levels.

What about guys running large turbos 70mm+ that run tons of volume and not much pressure? Would pre-injected metanol be more suited for them?
 
as far as mounting pre turbo is concerned, i really disliked the 90* elbow immediately pre-turbo because of its impedance to clean air flow. I went though all this trouble to get nice smooth intercooler and intake bends and i didnt like that i was 'just hanging it out in the wind'. what I did was mount two nozzles pre turbo on opposing sides of the intake pipe, with the mounting bungs cut to come in at roughly a 60* angle the nozzles protruded into the intake slightly and the spray pattern looked good in testing. sadly as i said, i never got the opportunity to try it on my car.

The problem with that is with both water and meth if the fluid sprays onto the sides of the intake pipe it will collect into larger droplets. Larger droplets will have more mass and can thereby cause damage to the wheel.
 
The problem with that is with both water and meth if the fluid sprays onto the sides of the intake pipe it will collect into larger droplets. Larger droplets will have more mass and can thereby cause damage to the wheel.

Agreed. that is the risk.
I believe with careful positioning of the nozzles this could work just as well if not better that the 90* both in the angle they are spraying at and the distance from turbo wheel that they are placed.

with the setup i used, becuase of how close the nozzles were mounted to the turbo very little, if any, moisture was present in the pipe. It was my belief that with a strong air current running through the pipe, no condensation would have been possible.
I know i have pictures on my old computer from my setup. I believe of my spray testing as well. ill look for them later today.

It just bothers me that in the above post about 25% of the cross section of the pipe is occupied by that elbow.

I also found that in my setup check valves were not sufficient to stop the trickle stop effect. the 5 psi crack pressure is too low. as the pump winds down and the pressure in the system drops. it does not stop on a dime.
I had the check valves directly mounted on the nozzles and their was still a period of very poor flow after the pump shut off. I designed my system to compensate for that with solenoids.

My setup was this.
pump on at 2 psi, post intercooler nozzle at 5psi, post tubo nozzle at 16 psi.
the pre turbo nozzles were run though the nitrous controls and a dash switch. if i hit the switch on the dash the pump was [ON] and the nitrous control was free to activate them at 2300+ rpm & above 70% throttle.

both post turbo solenoids were mounted pretty close to the the solenoids. the pre turbo ones each had a check valve on the nozzle and were mounted as close to the solenoid as the T-split would allow.
I understand this setup may not have been the best for the pump but it was the best (IMO) for the turbo.

in testing i saw virtually zero trickle down with this setup, but again it was never implemented so i have no real world data.
 
WRT increased efficiency from preturbo injection vs post turbo injection cooling. . . Those are two different animals. post turbo cooling (aftercooling) can never reduce the amount of exhaust energy required to spin a compressor at a certain rpm to achieve a certain volume flow. Preturbo injection allows less exhaust energy to be required to achieve a boost threshold because less heat is a result from compression Work required = Specific heat X Mass Flow X (Compressor T out - Compressor T in). Lower the Compressor T out, you lower the required energy from the exhaust to generate a certain flow. Thus you achieve a certain compressor rpm earlier in the rev range at a lower exhasut energy, and you shunt more exhaust straight to the tail pipe increasing the overall VE. Post compressor injection drastically cools the aircharge alone. But a more efficiency compressor with post compressor injection is more effective than a less efficient compressor with post compressor injection. Preturbo injection alters the "effective" efficiency of the compressor.

Theoretically, since cooling the air causes a pressure drop (due to contraction) one could argue that post turbo injection will allow the compressor to work more efficiently. Or put another way, for a given amount of exhaust energy the compressor will be able to do more work since there will be less backpressure in the intake to overcome.


How do you know the tempratures in the compressor scroll are exceding 212*F (boiling temp is vaporizing temp right?) at all times?

Keep in mind that the boiling point of a liquid is variable with pressure. So the boiling point of water will be greater than 212*F in an environment where there is 15psi above atmospheric. I doubt this will change anything in this context but just a thought.


When i was designing my system i bought, then threw out my progressive controller. I still wanted some form of a staged injection system, mostly because i run a small turbo and i run it at two different boost levels. My solution was to run a set of hobs switches to trigger two different nozzles at preset points. effectively giving me the correct amount of chemical intercooling at both my street and strip boost levels.

Maybe I'm not understanding this correctly but to run a two staged setup using a pressure/Hobbs switch you would have to have two separate pumps. Otherwise the lower pressure switch activates the pump and it's already working when you hit the second target pressure.:confused:

I suppose you could have the pressure switches activating inline solenoids in two separate lines although I like keeping things simple.

EDIT: Never mind, you wrote your last post while I was typing this out.LOL


The problem with that is with both water and meth if the fluid sprays onto the sides of the intake pipe it will collect into larger droplets. Larger droplets will have more mass and can thereby cause damage to the wheel.

I agree that you wouldn't want to be spraying the pipe directly. But keep in mind that the injection isn't working all the time. In fact, it's working for very brief moments when most needed. But there is always air moving through the system (as long as the motor is running) so any accumulating liquid might simply get evaporated.
 
I just still have yet to see any confirmed compressor wheel damage due to water injection preturbo, when the nozzle is directed to the hub.







romeen said:
Theoretically, since cooling the air causes a pressure drop (due to contraction) one could argue that post turbo injection will allow the compressor to work more efficiently. Or put another way, for a given amount of exhaust energy the compressor will be able to do more work since there will be less backpressure in the intake to overcome.
Efficiency is a function of compressor speed and volume flow. The compressor speed is also a function of volume flow. Increase the volume flow becasue of contraction and the compressor speed goes up. If compressor speed goes up, efficiency goes down; if you're anywhere at or to the right of the center efficiency island where 99% of us reside.

forcefed86 said:
Gotcha...

Makes prefect sense. But...

How do you know the tempratures in the compressor scroll are exceding 212*F (boiling temp is vaporizing temp right?) at all times?

I know it's pretty safe to assume the comp. scroll temps are in the mid 300* range on a small turbos (16g's etc) cranking out alot of boost. But once the water injected and starts cooling are you sure temps wouldn't be lowered to sub vaporization levels? I could see water being more effective with compound setup's or any setup generating over the "norm" heat levels.

What about guys running large turbos 70mm+ that run tons of volume and not much pressure? Would pre-injected metanol be more suited for them?
Adiabatic process is very predictable: Calculate compressor outlet temperature. No matter the compressor used (16g or s372), if it's at 70% efficiency where inlet tem is 100*F and ambient pressure is 14.7psia and youre seeing 30psi boost: output temp is 396*F . . . PLENTY to "flash" water to steam instantly.

Water injection post compressor is what it is: post compressor. Cooling the charger AFTER it leaves the compressor doesn't cool the charger IN the compressor. You still don't affect "compressor temp out" in the turbomachine work equation { Work required for compressor = Specific Heat X Mass Flow X (Temp out - Temp in) }.

Folks with larger turbos should be especially interested in the effect of wet compression, since the temperature output is not dependent on compressor size but where you're at on the efficiency map and what PR (boost) you're running. You see with that equation, if you decrease the "Temp out" at the compressor, then you lower the work required to spin the compressor to a certain flow. Thus you see the desired boost threshold earlier in the rpm range (lower exhaust energy required). This is why Turboglenn and everyone else reports faster spool.
 
Adiabatic process is very predictable: Calculate compressor outlet temperature. No matter the compressor used (16g or s372), if it's at 70% efficiency where inlet tem is 100*F and ambient pressure is 14.7psia and youre seeing 30psi boost: output temp is 396*F . . . PLENTY to "flash" water to steam instantly.

Water injection post compressor is what it is: post compressor. Cooling the charger AFTER it leaves the compressor doesn't cool the charger IN the compressor. You still don't affect "compressor temp out" in the turbomachine work equation { Work required for compressor = Specific Heat X Mass Flow X (Temp out - Temp in) }.

Folks with larger turbos should be especially interested in the effect of wet compression, since the temperature output is not dependent on compressor size but where you're at on the efficiency map and what PR (boost) you're running. You see with that equation, if you decrease the "Temp out" at the compressor, then you lower the work required to spin the compressor to a certain flow. Thus you see the desired boost threshold earlier in the rpm range (lower exhaust energy required). This is why Turboglenn and everyone else reports faster spool.

Well ya got me there! I'm stumped... Suppose I'll just have to believe you now. :applause:

Sure makes it a pain to have a seperate water and meth system though. Do you think that the meth will flash to quickly to achieve any percentage of Wet Compression?

I'm running the larger 250psi pump with a 7gph post and a .75 pre at the moment. I ordered an additional .75 nozzle that arrived yesrterday. I'm guessing I should be somewhere close to 2gph figuring in the additional pressure.

Do you think I would benefit from adding a small percentage of water to my tank? Say 10%?

thanks!
 
Maybe I'm not understanding this correctly but to run a two staged setup using a pressure/Hobbs switch you would have to have two separate pumps. Otherwise the lower pressure switch activates the pump and it's already working when you hit the second target pressure.:confused:

I suppose you could have the pressure switches activating inline solenoids in two separate lines although I like keeping things simple.

EDIT: Never mind, you wrote your last post while I was typing this out.LOL




I agree that you wouldn't want to be spraying the pipe directly. But keep in mind that the injection isn't working all the time. In fact, it's working for very brief moments when most needed. But there is always air moving through the system (as long as the motor is running) so any accumulating liquid might simply get evaporated.


Yes, now you are seeing where I am coming from.

Was it a simple setup? No, it was not. But it worked (in testing) the way i wanted it to function.My goal for the setup was to get the best pressure and atomization that i could and compensate for my two boost levels.


The relevant part of my experience is this. the 5 psi check valves do not with hold enough pressure to compensate for the slow (relative) depressurization of the pump. the use of check valves is sufficient to prevent siphoning while not under boost and prevent general leaking but not to hold back pressure.

It was my experience that having the pump at pressure before the inline solenoid opened and again having that solenoid close before the pump shut off was the best way to get maximum atomization and the least possible amount of trickle down, that in this case could lead to compressor damage.
 
The relevant part of my experience is this. the 5 psi check valves do not with hold enough pressure to compensate for the slow (relative) depressurization of the pump. the use of check valves is sufficient to prevent siphoning while not under boost and prevent general leaking but not to hold back pressure.

It was my experience that having the pump at pressure before the inline solenoid opened and again having that solenoid close before the pump shut off was the best way to get maximum atomization and the least possible amount of trickle down, that in this case could lead to compressor damage.

When you were using only the check valves was the amount of trickle down similar to what is shown in the video in post 64?

Or did having the check valve mounted directly to the nozzle holder help a bit? I wonder if nozzle orientation might make any noticeable difference, i.e. mounting it pointed straight up to get a little help from gravity?
 
Yes i would say it was similar. the trail off was the same, but the pissing out of the last little bit of fluid was longer in the video shown.
so yes. i got a fair amount of fluid that did not atomize at the end of the pulse.

this was much improved with the switch to solenoids.
 
FYI most all check valves that come with the kits are around 14lbs. Also the pump itself has a check valve that should prevent siphoning.
 
my setup with no type of check valve had major siphon issues I believe, I removed my intercooler this year after 2 seasons of meth injection, and to be completely honest there was about a litre of methonal in there!

Big learning experience however, I learned its better to use 2 small nozzles instead of 1 big nozzle, or 3 small ones etc.. stratigically placed ofcourse!

So either it was siphoning, or just wasn't atomizing properly? I was using a single nozzle from the AEM kit, and it was the largest that came with the kit.
 
Yes i would say it was similar. the trail off was the same, but the pissing out of the last little bit of fluid was longer in the video shown.
so yes. i got a fair amount of fluid that did not atomize at the end of the pulse.

this was much improved with the switch to solenoids.

I just bought another check valve in anticipation of adding a second nozzle. Makes me wish I had spent a few bucks more and bought the solenoid instead.


FYI most all check valves that come with the kits are around 14lbs. Also the pump itself has a check valve that should prevent siphoning.

Maybe that's the problem.
 
my setup with no type of check valve had major siphon issues I believe, I removed my intercooler this year after 2 seasons of meth injection, and to be completely honest there was about a litre of methonal in there!

Big learning experience however, I learned its better to use 2 small nozzles instead of 1 big nozzle, or 3 small ones etc.. stratigically placed ofcourse!

So either it was siphoning, or just wasn't atomizing properly? I was using a single nozzle from the AEM kit, and it was the largest that came with the kit.

Could be both... If you run a shurflo pump it has a built in internal check valve. Alot of times these get "crap" in them and no longer work. I'd take it apart and have a look. Sounds like this is what was happening to you.

The check valve on the nozzle is more for abruptly stopping the flow of meth once the pump shuts off. I run 7/16 SS braided lines on my "race car" and when the pump shuts off there is still alot of pressure and volume in the lines. The nozzle would continue spraying for quite some time after the pump quit. It was so bad my car would all but stall out after the burnout box.

I used dual 15gph nozzles on this car and 2gph pre. No check valve other than the one in the shurflow pump. Never had issues with siphoning. :confused:
 
Something has been on my mind lately.. maybe you guys can put it to rest.

If you have 250psi at the pump through one 15gph nozzle you would predictably have 250 psi - the loss of friction in the tubes at the nozzle head. If you sent that same 250psi into the pipe, and latter into a pipe of tripple the volume, would you not be working with 1/3 of the pressure? The pump only knows the what it sees in the first pipe, how could it supply the same pressure from a singe supply line to triple the volume?

that being said, at what point is the reduction of pressure worth the finer atomization afforded by the smaller nozzles. would three 5gph nozzles at 80psi atomize better than the single 15gph at 250? at what point does the reduction of pressure not to mention the increase in resistance from the multiplied friction start fighting a loosing battle?

I feel like i am missing a puzzle piece or two here guys, so forgive me if this is an ignorant question or if it is common sense that i lack. Help an electronics guy figure out the plumbing. :aha:
 
Something has been on my mind lately.. maybe you guys can put it to rest.

If you have 250psi at the pump through one 15gph nozzle you would predictably have 250 psi - the loss of friction in the tubes at the nozzle head. If you sent that same 250psi into the pipe, and latter into a pipe of tripple the volume, would you not be working with 1/3 of the pressure? The pump only knows the what it sees in the first pipe, how could it supply the same pressure from a singe supply line to triple the volume?

that being said, at what point is the reduction of pressure worth the finer atomization afforded by the smaller nozzles. would three 5gph nozzles at 80psi atomize better than the single 15gph at 250? at what point does the reduction of pressure not to mention the increase in resistance from the multiplied friction start fighting a loosing battle?

I feel like i am missing a puzzle piece or two here guys, so forgive me if this is an ignorant question or if it is common sense that i lack. Help an electronics guy figure out the plumbing. :aha:


If you are trying to relate this to electronics here is a good way.


Consider the pump to be a resistor. The pressure(voltage) drop across the pump(or pressure at the nozzle(s)) is related to the total system flow(amperage) that the system draws from the pump(resistor).

If the total flow is the same between 3 nozzles and one nozzle, the only difference in pressure at each nozzle is the slight extra flow resistance from the extra friction from more line surface area.


I don't know if that makes any more sense to you.
 
Our test went well. Check out this video from the inlet. This was injecting straight water through a 7GPH nozzle (rated at 150 psi), but with a 250 psi pump. Turbo is a HX-35. Figured I'd share this video because I thought it was pretty cool. I'm going to start a thread tomorrow with the details of our test.

YouTube - Pre-compressor water injection
 
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