Who uses Water Injection?
05-20-09, 03:48 PM
#28
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I have the FJO kit and I'm in the process of installing it now, just trying to decide where to put all the components and I'm also looking for a tank to use. If anyone has any suggestions please feel free to tell me. This is going on an FD btw.
Also, a thread I started a while back with similiar information...
https://www.rx7club.com/auxiliary-injection-173/ai-setup-do-you-use-why-817631/
Also, a thread I started a while back with similiar information...
https://www.rx7club.com/auxiliary-injection-173/ai-setup-do-you-use-why-817631/
05-20-09, 04:38 PM
#30
I use tap water as well.
The odd time if I'm gasing up and water is low, I grab a litre from the store and top off the tank though. Just a convience thing basically.
My car runs a snowperformance kit, "stage 2"
progressive controller.
currently in the car is the 380cc nozzle
mounted in TB elbow inlet (FC guy here)
150psi pump, not the big daddy 220something.
pump and tank mounted under right headlight, tank is custom, ~2.2L capacity.
Tank will last approx. one tank of fuel with a heavy foot. With a light foot it obviously lasts forever HAHA
Also, like anthony I do run a mix of either meth, or washer fluid towards the colder parts of our year to avoid any icing down there.
Car made 380whp last year on a SHAT tune with a SHAT turbine and a SHAT ecu only revving to 5900RPM
The best part though, at 380whp, it made 330ft/lbs TQ. Perhaps alot had to do with the stock ports, but the water IMO is certainly raising torque. You can't compress it, so you're running slightly higher dynamic compression when its spraying.
This year after many changes - EGT's at redline (around 8K) are about 875C @ 20psi from the T04-R with the WI. I should likely switch back to my larger nozzle to control them, but haven't started tinkering yet.
The odd time if I'm gasing up and water is low, I grab a litre from the store and top off the tank though. Just a convience thing basically.
My car runs a snowperformance kit, "stage 2"
progressive controller.currently in the car is the 380cc nozzle
mounted in TB elbow inlet (FC guy here)
150psi pump, not the big daddy 220something.
pump and tank mounted under right headlight, tank is custom, ~2.2L capacity.
Tank will last approx. one tank of fuel with a heavy foot. With a light foot it obviously lasts forever HAHA
Also, like anthony I do run a mix of either meth, or washer fluid towards the colder parts of our year to avoid any icing down there.
Car made 380whp last year on a SHAT tune with a SHAT turbine and a SHAT ecu only revving to 5900RPM
The best part though, at 380whp, it made 330ft/lbs TQ. Perhaps alot had to do with the stock ports, but the water IMO is certainly raising torque. You can't compress it, so you're running slightly higher dynamic compression when its spraying.
This year after many changes - EGT's at redline (around 8K) are about 875C @ 20psi from the T04-R with the WI. I should likely switch back to my larger nozzle to control them, but haven't started tinkering yet.
05-21-09, 11:22 AM
#32
06-15-09, 03:21 PM
#39
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Good info. That sounds about right. Based on this, we should establish what a/fs to tune for a certain boost increments. There are already a/f guidelines set up for non a/i pump gas boost pressures. We now need some for a/i.
06-15-09, 11:46 PM
#41
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Well I mean, usually when you raise boost, you richen it up as well. Most non-a/i guys run at around 10.5-10.9 A/Fs at 15PSI. Im running 11.5ish A/Fs at the same boost pressure due to my 315cc's of water.
06-16-09, 12:14 AM
#42
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Here it is http://www.lotustalk.com/forums/f160...ml#post1045017
Tuning and miscellaneous notes on water injection:
Always keep in mind that water injection is being used to suppress knock and permit tuning AFR to its maximum power levels. Water in excess of the amount needed for a safe knock suppression margin will hurt net output. Not leaning AFR enough or leaning it too much can result in decreased power levels.
The relationship that you should seek to manage with water injection is the ratio of water to fuel. Metered to exacting proportions as little as 3% water to fuel can replace the amount of heat absorption that fuel previously provided when leaning from 10:1 to 12:1 AFR.
Always keep in mind that water injection is being used to suppress knock and permit tuning AFR to its maximum power levels. Water in excess of the amount needed for a safe knock suppression margin will hurt net output. Not leaning AFR enough or leaning it too much can result in decreased power levels.
The relationship that you should seek to manage with water injection is the ratio of water to fuel. Metered to exacting proportions as little as 3% water to fuel can replace the amount of heat absorption that fuel previously provided when leaning from 10:1 to 12:1 AFR.
Also, this one is pretty interesting. http://www.max-boost.co.uk/max-boost/intake/WI.htm
06-16-09, 12:50 AM
#43
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Opps hit post too fast.
"We've seen that excess fuel is traditionally used as in-cylinder coolant. We've also seen here that water is a much better alternative for this purpose, since its latent heat is 6 -7 times higher than fuel (energy absorbed as the tiny droplets evaporate)
Latent heat of fuel = 350KJ/kg
Latent heat of Methanol = 1109 Kg/kJ
Latent heat of water = 2256KJ/kg
It appears that all you need is 3% water/fuel to replace two points of AFR (10.5-12.5). There is no performance gains in going richer than 12.5:1, and a lot less mass of water is needed to cool things down."
(sorry if this is already well known information.)
"We've seen that excess fuel is traditionally used as in-cylinder coolant. We've also seen here that water is a much better alternative for this purpose, since its latent heat is 6 -7 times higher than fuel (energy absorbed as the tiny droplets evaporate)
Latent heat of fuel = 350KJ/kg
Latent heat of Methanol = 1109 Kg/kJ
Latent heat of water = 2256KJ/kg
It appears that all you need is 3% water/fuel to replace two points of AFR (10.5-12.5). There is no performance gains in going richer than 12.5:1, and a lot less mass of water is needed to cool things down."
(sorry if this is already well known information.)
06-16-09, 04:45 AM
#45
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kk. Just trying to help and understand this stuff like everyone else. A lot of people are getting some amazing results, I can't wait to get my engine back up. (like all the people that are not running race fuel or AI of some sort lol. Although running AI or race fuel wouldn't have helped me lol)
Just trying to help and understand this stuff like everyone else. A lot of people are getting some amazing results, I can't wait to get my engine back up. (like all the people that are not running race fuel or AI of some sort lol. Although running AI or race fuel wouldn't have helped me lol)
06-16-09, 11:30 AM
#46
Before running wi i still didn't run so rich. I ran 11.3. at 15 psi but never exceeded 16 psi. When i added the wi i left the tune the same at 15-16 psi but then later when i trusted the setup i increased boost to 20 w/ 11 flat afr. I'll probably tune to 25 psi at 10.8 or so.
06-16-09, 05:00 PM
#47
For people using water only.
Dont go leaning it out while adding water.
Keep it rich. Have a good ignition system.
Thats the key to reliability.
Your not trying to subtract fuel for the amount of water added. This is the mistake alot of people make. ITS NOT METHANOL.
Dont go leaning it out while adding water.
Keep it rich. Have a good ignition system.
Thats the key to reliability.
Your not trying to subtract fuel for the amount of water added. This is the mistake alot of people make. ITS NOT METHANOL.
06-16-09, 05:46 PM
#49
I agree, while water can allow you to tune a bit leaner, the small amount of extra power isn't worth lowering the safety margin, that's one of the whole points of adding AI to the system. I like to tune to the middle/upper range of whats generally considered the limits on pump fuel alone. So if 11.5 @ 15 psi is considered the edge of being safe on 93 alone, I'll tune a a couple tenths of a point lower with water. Without water I wouldn't even attempt 20 psi, but my knock readings are right around 20 with 500cc water and 11.0:1 AFRs. I started out with around 10.5 afr, but I could feel a difference when I took some fuel out, and knock was the same so I left it there when I got to 11.0. So far I've run up to 22 psi and haven't had any issues with tuning this way.
06-17-09, 02:48 AM
#50
WaachBack
Mate i dont care for stupid internet articles.
I have done alot of wi tuning and MY REAL LIFE experience has shown me that pulling out fuel and replacing it with water is not using the power of water correctly. And pushing the envelope you will end up with a dead engine.
Im not going to argue with you, my experience has shown me lean mixtures only net good gains with weak ignition or STUPIDLY high amounts of water. Other wise running low 11s high 10s is a good place to be.
Mate i dont care for stupid internet articles.
I have done alot of wi tuning and MY REAL LIFE experience has shown me that pulling out fuel and replacing it with water is not using the power of water correctly. And pushing the envelope you will end up with a dead engine.
Im not going to argue with you, my experience has shown me lean mixtures only net good gains with weak ignition or STUPIDLY high amounts of water. Other wise running low 11s high 10s is a good place to be.