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Water Injection

F1R

Well Known Member
Does anyone have experience with water /methanol injection on a lycoming?

I am curious about some of the details when it was used in the early 1940's to prevent detonation at increased MP values for short term increased HP requirements.
Was the detonation protection partially from having steam cleaned / no hot spot cylinders or was it 100% from the chemistry change of the air fuel mix reacting with the water and methanol?

I am reasonably sure that some of the Reno air racers have experience but will they speak up?

Does anyone have bore scope photos of cylinders that have been run with the water injection from recent years at Reno?
 
No experience on a lycoming, though I did experiment with it successfully on a porsche engine with a home brewed turbo. These are horizontally opposed air-cooled, boxer engines, so similar to lycomings, though different chamber designs and smaller bores.

Water injection works through latent heat absorption. When exposed to heat from combustion, the water evaporates, and as it does so, it absorbs heat. The heat reduction is what reduces the detonation potential. It works the same way that your evaporating sweat reduces your body temperature. Normally combustion heat is reduced to below the detonation threshhold in high load conditions by moving it to the exhaust via retarded timing. Water injection allows more boost or more advanced timing by reducing the combustion heat with water evaporation. It is somewhat offset by the power reduction associated with the water displacing air/fuel mix. I forget the effect mehtanol has on the process, but it is about achieving a similar result without as much power reduction (unlike water, the methanol has energy potential during combustion). Most modern usage is a blend of water/methanol. I used commercial windshield washer fluid in my setup.

Larry
 
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I have used it

Does anyone have experience with water /methanol injection on a lycoming?

I am curious about some of the details when it was used in the early 1940's to prevent detonation at increased MP values for short term increased HP requirements.
Was the detonation protection partially from having steam cleaned / no hot spot cylinders or was it 100% from the chemistry change of the air fuel mix reacting with the water and methanol?

*Neither. The injected mixture cools the combustion event to a temp below the detonation level.

I am reasonably sure that some of the Reno air racers have experience but will they speak up?

*I raced at Reno with several different setups. One setup also sprayed the oil cooler to help control that temp too. Turned out that the proper ratio of ADI worked better: about 20% of the fuel flow, tho more - 30% - did a better job.

Does anyone have bore scope photos of cylinders that have been run with the water injection from recent years at Reno?

*I never took pictures, but I can say the plugs were always clean.
 
Boss,

Where did you spray the water/methanol in? Did you have one or two large nozzles ahead of the servo body or 6 smaller lines and a nozzle in each of the intake tubes?
 
ADI injectors

I tried several methods - the best (which was not REALLY the best) was a single nozzle into the fuel controller. I found that the 550 swoopy intake system (Cirrus type engine) was not really good at putting even amounts of ADI into each cylinder.

Since I have added the DanH round inlets for proper cooling, the ADI system is on the shelf. That system weighed at least 70lbs when full (7gal tank, + 10lb pump).

My next build has a supercharger on a low compression 550 - that I expect to push past TCM parameters - has a 6 point (2GPH each injector) setup so each cyl does get the same amount. I also added a Devil's Own controller to get some sort of control of the spray at lower boost levels, and a lot more at higher levels.

The fuel and ignition are SDS parts.

Using the same cowling shape, I expect to not need the ADI as long as I stay within the TCM power chart (38"/2700/350hp). That expectation might be over the top - could be my system does not care what TCM says about their twin turbo setup.

I am thinking that 42-44" might be OK with the ADI running at 20% of FF (likely close to 45GPH without ADI, but more like 35-38 with ADI), but only experimenting will give me that answer.

Yes - the airframe has been 'modified' to allow the use of such power levels, and it's resultant TAS numbers.

As I have said before - it will be GREAT - especially if it works!:D
 
I tried several methods - the best (which was not REALLY the best) was a single nozzle into the fuel controller. I found that the 550 swoopy intake system (Cirrus type engine) was not really good at putting even amounts of ADI into each cylinder.

I have added the DanH round inlets for proper cooling. "


Just curiuos if all the new F1 Cowl inlets are round or are they still the rectangular slots previously used? One of the slide show photos on your site show a carbon fiber cowl with round inlets.

Screen-Shot-2018-08-26-at-8.07.20-AM-e1535292750904.png


And a smuggled photo of the F1 skunk works shop ( location unknown) molds for the hopefully available to all F1 owners new cowls?
Screen-Shot-2018-08-26-at-8.06.58-AM-e1535292954349.png
 
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My dad ran water vapor 'injection' on a '59 Studebaker Lark 6 cylinder. (Newer technology than a Lyc, but only by a little bit).

He always claimed that it improved the gas mileage and performance. I can't verify; I was too young to drive back then. But guess what; you can still buy the technology today! Should work fine on a Lyc; it's only slightly older than the Studebaker.

http://www.watertogas.com/water-gas-injector.html

https://www.google.com/search?q=water+vapor+injection+bubbler+jar&oq=water+vapor+injector+&aqs=chrome.3.69i57j0l5.12182j0j7&sourceid=chrome&ie=UTF-8

;-)
 
I am only seeking a good, safe, quick and effective method to clean out the lead and carbon deposits.

There is a really informative video on the important data collected by a NACA test report from 1944 where they were able to more than double the HP from a V12 by the use of straight water injection. Details are here:
1PA70pN6zPM

or start at the beginning for a good bit of background and lead in.

It gets much more interesting when methanol was added to the mix.

I like the Devils Own auto systems that meter proportionately to fuel flow and boost for super charged and turbo charged engines.

However, since I only intend on clean up before bore scope time, I should be able to regulate a single nozzle to flow about 20-30% of my 1 liter per minute(15 gph) of fuel flow.
 
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Easy!

I am only seeking a good, safe, quick and effective method to clean out the lead and carbon deposits.

There is a really informative video on the important data collected by a NACA test report from 1944 where they were able to more than double the HP from a V12 by the use of straight water injection. Details are here:
1PA70pN6zPM

or start at the beginning for a good bit of background and lead in.

It gets much more interesting when methanol was added to the mix.

I like the Devils Own auto systems that meter proportionately to fuel flow and boost for super charged and turbo charged engines.

However, since I only intend on clean up before bore scope time, I should be able to regulate a single nozzle to flow about 20-30% of my 1 litter per minute(15 gph) of fuel flow.

You can use an RV water pump, or a garden hose connected to your house, then to the nozzle. You can use spray nozzles from a misting system, but those are generally fairly small - be picky about the size so it is large enough. I would say that you should run the engine at 50% power for about 5 min to see if that is enough to clean things up. If it is still dirty, give 'er another shot!

Rig the nozzle so it sprays into the carb/fuel controller, and turn on the water after the engine is warm, and you are happy with the power setting. I doubt you will need full power, nor will you need any methanol.

Be sure to use distilled water.
 
how do you guys make sure there is no detonation? i was once contemplating a possibility of installing a race-car water/methyl injection, but how do you know that it works as expected?
 
how do you guys make sure there is no detonation? i was once contemplating a possibility of installing a race-car water/methyl injection, but how do you know that it works as expected?

Just as with almost everything in life, there are no guarantees.

However, if you have ever heard a 65 ford with a high CR 390 that mom or dad did not shift down for a corner and too much throttle was applied while the RPM's were too low.... you will never forget that sound for the rest of your life. It is like a ball peen hammer is beating on the end a 20 foot length of 6" shaft. Of course you never want to hear that but you will be acutely aware of the onset conditions before it manifests.

Other clues... know your EGT's and CHTS well for a given power setting, at a normal high power cruise. Then turn on the H2O injection and monitor the flow rate. Is it 20% to 30% of your fuel flow rate at that power setting? Watch the CHT's drop. Do they all drop even or are there one or two above the others ? If so, your nozzle system is not distributing evenly and forget about increasing boost and power settings until you get that solved to where you see nice even CHT drops and even EGTs to match.

A single large nozzle ahead of a supercharger inlet will normally get the water thoroughly mixed into the air. At least until the air makes a few high speed bends in the intake tubes.

Individual spray nozzles in the intake ports is the ideal situation but more complex to set up.

Test thoroughly to make sure it works reliably at safe power settings where you have no issues without it operating. Then proceed incrementally after that.
 
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For the doubting Thomas

how do you guys make sure there is no detonation? i was once contemplating a possibility of installing a race-car water/methyl injection, but how do you know that it works as expected?
K46IJV0Lg24


Here is a $12,000 STC'd version for a continental 520. Check out the location of the injection nozzles, just in front of the throttle plate. Also the MP and CHT values they chose to initiate the flow at. This should provide you with a good idea of what to monitor if you are trying to set up your own system.
 
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