Kewl! (I figured such was the case)

Thanks David.

 

Allison's were only run in the initial version of the P-51. It was a dog at altitude to the Brits started putting in the Rolls Merlin with is a much better engine. The rest was history.

You must be working on tractor puller engines and not war bird because nobody (that I know of) runs the Allison in the war bird Mustangs.

By the way, in a twist of irony, Rolls Royce had aquired Allison from GM! I saw it designated on a helicopter engine my (16 year old) son was working on.

As to not completely hijak this thread, you can water inject turbo shaft engines also.

I used to run an Edelbrock "Veri-Jection" system on a high compression muscle car, and the instructions were to keep increasing the flow until the engine boggs, then back it off just like dave has been saying. I ran high levels of straight water in that engine and when I finally pulled it apart at 230K the pistons, valve heads, and combustion chamber were perfectly clean. I would not have believed it had I not seen with my own eyes.

Another point is many years ago an old timer told me that when he would get cars into his station that were running rough because the cars wern't blown out on the freeway enough, and he would drive the car to that back of the shop, rev the engine and pour a cup of water down at a rate that the engine would be bogging but still maintaining high RPM's. It works like magic.
I have since performed this trick many, many times and never hydrolocked an engine.

Do what Dave says, and you will be in good shape.

 

Fluid dynamics is a deep science. Sorry, just couldn't resist....

There are many variables and unknowns when comparing installations. The true diameter of every millimeter of pipe, tubing and fittings plays a part. The number and radius of bends compared to diameter is a key factor. Turbulence, cavitation, and vortices can effect overall performance of two seemingly identical systems. Flow restrictions may come from an imperfect bore on an injector, or a less than perfect fitting, a strand of teflon tape or a wad of pipe dope in the lines. Temperature variables can have a dynamic effect on flow as can the materials used for actual piping. Relative pressure of the atmosphere into which the mixture is injected will have a profound effect on output from the nozzles as will the flow characteristics of the manifold into which it is injected. Remember, these are the things of Fluid DYNAMICS and Thermal DYNAMICS, not Fluid linears and thermal linears. That is to say it is a 'Team Sport' which relies on the performance of every player, in addition to the coach and manager, in order to realize the full potential in any given situation.

It is therefore necessary to adopt a process of trial and error in order to 'dial in' any given system to its application.

I just got done watering the garden with several thousand dollars worth of assorted pump, piping, fittings, hoses and a nozzle. The mfgrs. and installers claimed variously that 75-80 psi output was no problem, and maybe I'd even better call for help holding the nozzle. Somehow their data was skewed as I think an 8 year old boy could generate a better stream than what was coming out this morning! Cooling Mist and Snow do their best to give a topnotch dependable product but regardless they are at the mercy of the mfrgr. and vendor of parts and the home installer who does the fitment. Once the products leave their shop it MUST BE trial and error according to particulars of a given installation, no getting around that.

JimmieD

 

Wise words there JimmieD.

It is amazing how complicated a simple Tank > Pump > Nozzle(s) install can be. As is covered in you first paragraph of fluid dynamics, fitment can have a dramatic impact on outcome.
In my mind, compared to what we strive for here in this thread, the OEM feed-horn stinks as far as an input for fog. It's no where near centrally located. The intake log (as it were) is full of bumps. The individual runners aren't truly equal flow wise. Cleaning up the bowls would help.

Direct injection would certainly rectify all concerns discussed here.

Frankly, it seems we're splitting hairs with an axe. We've pretty much got to make lemonade out of it.



All too often though it turns out someone inevitably installs it upside down and blows our doors off.

 

Yes, but educated guesses can go a long way to shortcut the process. Anyone could look at that dual airhorn and see which branch would be the path of least resistance in a non forced flow. Boosting changes the equation entirely for a dry flow of air, but when heavy water vapor is added to the column the flow characteristics change yet again.

So I guess I'm agreeing with you.

 

Ah! We've come full circle.

I'm envisioning a sort of stratifying of the fog in the charge-air flow with the twists, turns, and wyes (ignoring impingment).

It's that we address.

 

Geez...I think I'm even more confused now. It's great having everyone's input here though!

It seems both Loch and Wanna have dual 10gph nozzles and have no problems making the motor bog. So, either the rating system of Coolingmist's nozzles is way off or the pump is not putting out the same (ie. enough) pressure.

You guys running the homemade and Snow setups, does your pump have a pressure switch on the top like mine in the pic? Is the pressure switch being used in your setups? Dave from Coolingmist advised me to bypass that pressure switch to get a slightly increased max psi (and I like the idea of the pump not going to 150psi, then dropping back to 100psi, then kicking on again to 150psi...seems a consistent steady pressure would give better results). I know all of you guys with these other W/M systems use the little allen head on top to adjust pump pressure, but for some reason David told me not to touch that setting. I am dying to give it a few cranks and see if the pressure goes up like it should.

 

You by-passed the switch on the pump, so it has the highest pressure. Our nozzles are exactly the rating we stated.

changing the pressure switch will do nothing if you bypassed it. If you want to change the pressure switch feel free, just remove the bypass and change it. Crank it all the way to the right. I will do the same thing.

I wouldn't get all caught up on trying to make your motor bog and I wouldn't get all caught up in someone elses engine that is bogging. Your vehicle and setup is completely different.

David

 

Yeah I'm looking at the pressure switch as well (haven't touched it though) as my tank levle isn't dropping like I thought it might.

Lemme go get a new carwash brush and lower all the start/full-on settings. Try hard to bog it.

BRB

 

jrussell

I have to use the pressure switch to control the volume of flow. The Snow controller is not as flexible as the Coolingmist unit so there is no way I could run with the switch bypassed. The Snow controller starts at 50% duty cycle, which with the switch bypassed would bog the motor at anything less than full power. My pump switch is set so that I do not have the engine stumbling at system cut-in under "less than full power" driving. More pressure causes it to stumble when I roll out of the throttle to shift, or at high rpm and moderate acceleration.

Like David said, if you have the switch bypassed there is no benefit to messing with it.

 

David,

It seems that something just doesn't add up here. Loch is using Aquamist nozzles and Wanna is using Snow nozzles. Both of these companies rate their nozzles at 10gph and they are both experiencing approximately the same flow. My truck/setup is not that different from these guys and if anything I should not be able to inject as much W/M since they are running much more fuel than I am.

It seems pretty unlikely that both of the other companies' rating systems are off, yet they still coincide with each other. Maybe the supplier of your nozzles uses a completely different type of rating system (ie. rated under different conditions or using different liquids)?

We've established that there are many variables between systems and the ratings are really nothing more than a guide. However, there is no possible way my 32-33gph nozzles are flowing more than their 20gph ones...especially not 50% more. I wonder why there is such a huge difference between the ratings?

 

I am not commenting on the other companies nozzles, thats not my place. The nozzle you have (the one we sent you in the mail) flows 16 GPH @ 150 psi. Im sure your pump is not pushing the entire 150 psi since you have 2 nozzles hooked up, you may only be at 100 with 2 nozzles and when you calculate your boost. I just picked that number out of my head, but my point should be made. The nozzles are designed to atomize as low as 40 psi.

Obviously we are not going to release a nozzle and flow rates that are rated for another liquid.

Also, to be clear the original 16 GPH nozzle that you were sent is NOT equal to the one that we sent you in the mail. The one we sent you in the mail will atomize and flow better as the inside is different.


David

 

Same point I made a page ago.

David, thank you for not making this into a brand war between the water/meth systems. That's not what this is about.

The point I was trying to make when I said that somebody's rating system must be off is that it's not the flow number that is important, it's the effect the nozzle has on the motor.

From my discussions with Jim Fulmer before I got involved in water/meth I learned that the maximum HP benefit is obtained just before the engine stumbles. That is why I am so concerned with being able to bog the motor. I don't care what the nozzle says, if it can't bog the motor you can make more power with a bigger nozzle (assuming you have the pump capacity to atomize the water/meth).

I believe this also applies to EGT reduction. More water vaporizing = more heat absorbed.

 

Ok, after going back and looking at some older posts I think the issue is that the different companies rate their nozzles at different pressures. Wanna is using dual 10gph nozzles, but that is at only 60psi. I'm sure his nozzles would be closer to 16gph when at full pressure (100-150psi). Loch's flow rate was from an actual test of his nozzles and not a company's rating (19gph total). It would not surprise me if dual 16gph "rated" nozzles only flowed at a true total of 19gph when taking into account filters, restrictions, and boost. I assume the ratings for most nozzles are done on a bench and not installed in an actual vehicle?

David, have you put a pressure gauge on a large dual nozzle setup like mine to see what the system is actually pushing at 50%/75%/100% duty cycles?

 

Ok, let me better explain. Nozzles are rated in Gallons Per hour. The one we sent you is approx 13 GPH @ 100 or 15.92 GPH @ 150.

If you are at 150 psi water pressure the nozzle would be putting out rougly 16 GPH. If you had two of those and were at 150 psi you would be at 32 GPH.

here is how you calculate flow with our system.

Take the known rating and the known pressure. In this case your known rating is 13 GPH and your known pressure is 100 PSI. Taking a single 13 GPH nozzle here is your chart:

150 psi = 15.92 GPH
125 psi = 14.53
100 psi =13
90 psi =12.3
80 psi =11.62
70 psi =10.87
60 psi =10.06

To calculate yourself use the following formula

Known_pressure = 100 psi
Current_pressure= what ever your water pressure gauge shows

GPH=known_pressure * SQRT(current_pressure/known_pressure)

in otherwords to get the gallons per hour at whatever psi you want (Up to 200 psi) just follow that.

There is nothing magic about it. X amount of pressure into your your nozzle produces X amount of flow. Things like the amount of boost you are running of course has effects as well.

David