Decarbing - Before and After Rotor Pics
the difference won't be dramatic but it should be notable. there's many factors you won't take into account such as ambient temperatures and the injection amounts. 230cc is not a large injection amount so the results won't be as noticeable. if you were out on a hot day and took an accurate measurement without the water and then took one with say 350-400cc you should see the results.
also if you're using the "catalyst" as an EGT probe the numbers will be even less noticeable. it's just too far downstream and taking an average exhaust temp at that point. you could place probes between the turbo and manifold or at the turbine outlet, those points are where the EGTs will be in the 1600F range and also where you will more accurately find the breaking point of an engine.
Rotary Evolution
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From: Central FL
i have a feeling its just due to the MSP absorbing the work done by the inert gas and the lower volume just giving less impact.
on the 500whp engines spraying twice that amount the net is usually about 100F difference, but that is with a peripheral exhaust engine and also at over 20psi of boost(not that i recommend it with a renny, so don't).
on the 500whp engines spraying twice that amount the net is usually about 100F difference, but that is with a peripheral exhaust engine and also at over 20psi of boost(not that i recommend it with a renny, so don't).
Last edited by Karack; Feb 10, 2014 at 05:07 PM.
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From: Hanover, IN
Saw this thread and wanted to add a method to control the amount of fluid that is injested and no vacuum leaks. See link below. It uses the windshield washer fluid tank to act as a water/alcohol injection system. I build mine for less than 10 bucks and 30 minutes. I made mine slightly different, but works GREAT. I can cycle Seamfoam, water, alcohol, or any combination with control of the rate the engine vacuum sucks in the fluid.
https://www.rx8club.com/series-i-do-...-5-mins-55517/
https://www.rx8club.com/series-i-do-...-5-mins-55517/
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I'm glad to see someone actually took the time to truly verify what happens with this procedure. I've steam cleaned my RX-7 engines this way for years and could only tell you that they run better afterwards. I had no true way of knowing exactly what was happening inside. It was always just assumed to be removing carbon deposits. I run a vacuum hose into a gallon of water. The other end is just a nipple on the manifold. I hold the engine around 3K rpm. It generally takes me about 5 minutes to get an entire gallon through the engine! I do a gallon per rotor. I've always done it this way and it has always worked just fine. The scary part is realizing how much more water there is inside the engine than there is fuel. It's amazing that it runs at all.
rev it up
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From: Brisbane Australia
It is a good idea to do a oil change post water decarb. I have done this a couple of times and it is a very simple process.
There are two nipples so the water is injected into each rotor separately. I guess the car is running on one rotor.
Also a good idea to start with a fully charged battery in case the car gets flooded....happened to me once.
There are two nipples so the water is injected into each rotor separately. I guess the car is running on one rotor.
Also a good idea to start with a fully charged battery in case the car gets flooded....happened to me once.
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skc, who is that directed to?
I started this thread with testing a year ago, and I have a couple videos posted that show exactly how I had it set up. I never had any flooding trouble, since the engine was running for all but 1 test method, and that method just had seafoam in 1 rotor.
I started this thread with testing a year ago, and I have a couple videos posted that show exactly how I had it set up. I never had any flooding trouble, since the engine was running for all but 1 test method, and that method just had seafoam in 1 rotor.
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I would guess that it would be similar to the increased pressure of a turbocharger of the right boost level, only without the added exhaust port temp increase and without an increased risk of detonation.
I wouldn't think there would be any concern. Do you have a different perspective on that?
I wouldn't think there would be any concern. Do you have a different perspective on that?
Rotary Evolution
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decarbing is similar to water injection, and none of those engines ever showed any abnormal wear or spring tension issues on the seals. carbon buildup does however wear the spring ends to a sharp edge which digs into the seals and also reduces spring tension though.
the presence of water doesn't stress the springs any harder than normal combustion does.
the presence of water doesn't stress the springs any harder than normal combustion does.
I would guess that it would be similar to the increased pressure of a turbocharger of the right boost level, only without the added exhaust port temp increase and without an increased risk of detonation.
I wouldn't think there would be any concern. Do you have a different perspective on that?
I wouldn't think there would be any concern. Do you have a different perspective on that?
decarbing is similar to water injection, and none of those engines ever showed any abnormal wear or spring tension issues on the seals. carbon buildup does however wear the spring ends to a sharp edge which digs into the seals and also reduces spring tension though.
the presence of water doesn't stress the springs any harder than normal combustion does.
the presence of water doesn't stress the springs any harder than normal combustion does.
in my head i envision some added spring tension from the buildup of steam within the chamber.
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2 reasons that I see:
1) The water flashes to steam, which IS compressible (you are thinking of when the entire rotor face is full of water)
2) The pressure from combustion and steam expansion isn't on the same plane of motion as the springs. It's pushing sideways on the seal, but that is perpendicular to the motion of the seal and spring, so the seal wouldn't be moving from any pressure increase to be putting pressure on the spring.
1) The water flashes to steam, which IS compressible (you are thinking of when the entire rotor face is full of water)
2) The pressure from combustion and steam expansion isn't on the same plane of motion as the springs. It's pushing sideways on the seal, but that is perpendicular to the motion of the seal and spring, so the seal wouldn't be moving from any pressure increase to be putting pressure on the spring.
2 reasons that I see:
1) The water flashes to steam, which IS compressible (you are thinking of when the entire rotor face is full of water)
2) The pressure from combustion and steam expansion isn't on the same plane of motion as the springs. It's pushing sideways on the seal, but that is perpendicular to the motion of the seal and spring, so the seal wouldn't be moving from any pressure increase to be putting pressure on the spring.
1) The water flashes to steam, which IS compressible (you are thinking of when the entire rotor face is full of water)
2) The pressure from combustion and steam expansion isn't on the same plane of motion as the springs. It's pushing sideways on the seal, but that is perpendicular to the motion of the seal and spring, so the seal wouldn't be moving from any pressure increase to be putting pressure on the spring.
Again, far fetched
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My counter to that would be: If steam can do that, then the combusting air/fuel mixture can do it too under normal driving.
Combustion pressures on piston engines with some quick googling show 1,000psi+. I wouldn't think water injection or ingestion is increasing that appreciably.
Combustion pressures on piston engines with some quick googling show 1,000psi+. I wouldn't think water injection or ingestion is increasing that appreciably.
My counter to that would be: If steam can do that, then the combusting air/fuel mixture can do it too under normal driving.
Combustion pressures on piston engines with some quick googling show 1,000psi+. I wouldn't think water injection or ingestion is increasing that appreciably.
Combustion pressures on piston engines with some quick googling show 1,000psi+. I wouldn't think water injection or ingestion is increasing that appreciably.
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If you just let it sit in the engine soaking stuff, yes.
If you ingest it with the engine running, it does clear carbon, but distilled water is just as effective in that circumstance. And seafoam is $11 for 16oz ($88 per gallon) vs distilled water at $0.99 a gallon, and even then you still have to run quite a bit of it through for any significant carbon removal.
If you ingest it with the engine running, it does clear carbon, but distilled water is just as effective in that circumstance. And seafoam is $11 for 16oz ($88 per gallon) vs distilled water at $0.99 a gallon, and even then you still have to run quite a bit of it through for any significant carbon removal.
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From: Central FL
and i would even consider distilled water as unnecessary but could be harmful to those who have catalysts still. even then i doubt it would offer a measurable difference. distilled water is necessary for water injection systems because the water can sit dormant in the system for long periods of time and clog nozzles, pumps and strainers.
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RIWWP, great thread!
I had been thinking about water injection as a way to clear carbon for years and it looks like you have proven it works. Your compression tests before and after are proof that this procedure shows real benefits for increasing compression.
Have you ever tried driving the car with this cleaning set up. Not as a day to day set up but just to run a gallon or two through the system. The car would be under load and this may increase the effect. Not sure about the effect on the CAT?
I had been thinking about water injection as a way to clear carbon for years and it looks like you have proven it works. Your compression tests before and after are proof that this procedure shows real benefits for increasing compression.
Have you ever tried driving the car with this cleaning set up. Not as a day to day set up but just to run a gallon or two through the system. The car would be under load and this may increase the effect. Not sure about the effect on the CAT?