Water Injection - Long-drawnout, Unorganized Post.
07-09-2003, 01:44 PM
#1
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Join Date: Sep 2002
Location: bay area
Posts: 235
Just curious, I recently installed WI on my 3rd gen Rx7. I'm very, very excited about this set up. I did 90 pct of the work and made sure its a very clean installation. I got my inspiration from other kits on the net, but made mine custom for the FD. I even made a custom DIN panel with LED lights to show various stages of activation, and to arm/disarm the system, and while I started with a 6 QT water tank, I now have found a 3 gallon tank that fits perfect in the spare tire bin, so I installed that yesterday..
I have not extensively tested this sytstem, but I found that heatsoak doesn't seem to exist anymore. I park the car and of course my small BLITZ SMIC heatsoaks and my intake temps are 75 on my commander, but as soon as I boost, the temps drop very fast. My guess is the heat soak is not relevant since the temps are cooled by the water after the IC anyway. So driving around town with the WI off, my air temps would steadily increase, specially if driving slow. I found that just from hitting boost from climbing a hill or whatever, my intake temps during city driving stabilize and never climb to the crazy numbers that they did previously. Keep in mind this is just 1 days worth of testing I need to do more testing to get the big picture.
Im curious if any of you have WI, what boost do you set it to come on? Do you notice any difference on a hot day? Any Dyno numbers, track #'s to back it up?
I know that the purpose of WI is not really to lower intake temps, that more a good side effect, and the purpose is to raise resistance to detonation.
I currently have it set to come on at 8 PSI. I was considering to get a RPM switch that only activates it after 4000 RPM. I had some concern because I hit 8 PSI easily by 2200 in 5th gear. But from my driving, it doesn't seem to be causing problems to have the water inject that low of an RPM, is this safe? Im not worried about having to fill up the tank.
I have not extensively tested this sytstem, but I found that heatsoak doesn't seem to exist anymore. I park the car and of course my small BLITZ SMIC heatsoaks and my intake temps are 75 on my commander, but as soon as I boost, the temps drop very fast. My guess is the heat soak is not relevant since the temps are cooled by the water after the IC anyway. So driving around town with the WI off, my air temps would steadily increase, specially if driving slow. I found that just from hitting boost from climbing a hill or whatever, my intake temps during city driving stabilize and never climb to the crazy numbers that they did previously. Keep in mind this is just 1 days worth of testing I need to do more testing to get the big picture.
Im curious if any of you have WI, what boost do you set it to come on? Do you notice any difference on a hot day? Any Dyno numbers, track #'s to back it up?
I know that the purpose of WI is not really to lower intake temps, that more a good side effect, and the purpose is to raise resistance to detonation.
I currently have it set to come on at 8 PSI. I was considering to get a RPM switch that only activates it after 4000 RPM. I had some concern because I hit 8 PSI easily by 2200 in 5th gear. But from my driving, it doesn't seem to be causing problems to have the water inject that low of an RPM, is this safe? Im not worried about having to fill up the tank.
07-09-2003, 04:59 PM
#6
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Join Date: Nov 2002
Location: PHX
Posts: 265
I have not noticed much reduction in air temps, but I did pull my plugs after about 6 months of water injection and they sure are alot cleaner than I expected!
I have it set to come on at 7psi. I dont remember what size sprayer I am using though. I have no dyno data, no track data, and I dont feel any extra power. I did it to reduce the chance of detonation, so I am not tuned for water.
I have it set to come on at 7psi. I dont remember what size sprayer I am using though. I have no dyno data, no track data, and I dont feel any extra power. I did it to reduce the chance of detonation, so I am not tuned for water.
07-09-2003, 05:06 PM
#7
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Join Date: Oct 2001
Posts: 190
Mine comes on at 7 psi (like I said in the other thread).
I'll post up if I see lower operating temps at the road track this weekend, but I doubt I'll see any difference.
I was going to mention that I looked into RPM switches and all were $150+, but I just looked at Summit's website again, and it looks like they have a cheapo switch for $45. Although if the car runs fine at 2200 rpms, 8 psi with water and is not stumbling then I wouldn't worry about it too much. If at some point you up the water amount and it starts stumbling or killing it might be time for a switch. Or you could just downshift...
There are more than 3 users... a few more on the other forum, and another guy I know locally uses it.
I'll post up if I see lower operating temps at the road track this weekend, but I doubt I'll see any difference.
I was going to mention that I looked into RPM switches and all were $150+, but I just looked at Summit's website again, and it looks like they have a cheapo switch for $45. Although if the car runs fine at 2200 rpms, 8 psi with water and is not stumbling then I wouldn't worry about it too much. If at some point you up the water amount and it starts stumbling or killing it might be time for a switch. Or you could just downshift...
There are more than 3 users... a few more on the other forum, and another guy I know locally uses it.
07-09-2003, 07:49 PM
#8
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Join Date: Sep 2002
Location: bay area
Posts: 235
ok, so mine comes on at 8 PSI, mine is the 6.32 GPH nozzel. I guess you guys are in the same boat as me, in 5th gear going up a hill, your injecting water too.
I did mine as something to prevent detonation also, not to be faster, but if it helps, great.
I have not redlined it yet with the water injection. What happens if you spray too much water when you are redlining, can you damage your engine?
I did mine as something to prevent detonation also, not to be faster, but if it helps, great.
I have not redlined it yet with the water injection. What happens if you spray too much water when you are redlining, can you damage your engine?
07-10-2003, 01:29 PM
#9
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Join Date: Oct 2001
Posts: 190
With that pump (assuming you bought the pump from the DIY instructions) you'll be pumping the same volume of water at 3000 rpms as at redline. I can't imagine it would hurt the engine...
I have redlined mine plenty since install with no problems. I am running a 1.9 gph nozzle I believe, FYI. (Went small so that my 1 quart windshield washer container would last through a whole 20 minute track session.)
I have redlined mine plenty since install with no problems. I am running a 1.9 gph nozzle I believe, FYI. (Went small so that my 1 quart windshield washer container would last through a whole 20 minute track session.)
07-10-2003, 02:12 PM
#10
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Join Date: May 2002
Location: California
Posts: 22,465
Originally Posted by Tom93R1' date='Jul 9 2003, 01:59 PM
I have not noticed much reduction in air temps, but I did pull my plugs after about 6 months of water injection and they sure are alot cleaner than I expected!
mike