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My mechanical preturbo water injection
I did a writeup about 9 months ago on the "other" forum, I've decided to include the information over here to hopefully get more exposure/interaction on this site. Here are the main points I was looking for when I first decided to add the water injection. So taken from my first post on 12-15-08....
"1) The system design I'm using is mechanical and should have a lower chance of failing 2) Water is free/easily attainable 3) My car is mainly a street car and I'm just looking for a bit more boost with the added reliability of AUX injection 4) I'm cheap and like to do things myself" When I first decided to add the water I was at 15psi on a t61, my plan was to run 200-300cc of water @ 18 psi or so. I'm now running a t70 @ 23 psi daily and about 600cc of water. All on 93 premium pump fuel. The system uses no pumps, controllers or other electronics. The only electrical components are a solenoid, and a boost switch similar to a hobbs. It works by using boost pressure from the turbo to pressurize a sealed water tank, this forces the water through the line to the atomizing water nozzle. The nozzle has both a water and an air port to atomize the water very finely. The air port receives boost pressure from the turbo. Located before the atomizing nozzle is a solenoid which is activated at a preset boost pressure by the hobbs style switch. The water is fed directly into the turbo inlet. The key is to have the water fully atomized before it enters the engine. This prevents any compressor blade erosion from occurring. The benefits to preturbo injection, beyond the benefits of aux injection in general are. 1)Water is better atomized, allowing easier combustion & faster heat absorption 2)Lower Intake temperatures 3)It shifts the compressor map giving the turbo more efficiency at high boost levels. (much like the turbo is physically larger) My system has gone through a few alterations in the past 9 or so months, and I'll try to cover each of the phases in different posts to keep it somewhat separate. The next post will go into details of the parts used, along with some pictures. Stay tuned. |
This sounds like a great idea, i'm surprised nobody has thought of using the boost pressure to make a mechanical injection system. I too prefer mechanical systems as they are much less likely to fail, i'm interested to hear more.
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Any pictures of the set up?
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Alright the parts I used are:
1)Atomizing nozzle from http://www.spray.com/cat70/f/F16.html part number is sue18, in stock form it flows 380cc at 20psi. I started with it like this and a few months later drilled it out to flow 500cc at 20 psi, and close to 600 cc at 23 psi. http://i10.photobucket.com/albums/a1...n/dsgagaga.jpg 2)I have a well built polypropylene tank from US plastics almost a gallon in size. http://i10.photobucket.com/albums/a1...aaan/8665p.jpg 3)An adjustable pressure switch purchased from a aux injection website. http://i10.photobucket.com/albums/a1...switch_L-2.jpg 4)A spare nitrous solenoid to cut water flow. 5)Various hoses. Before ordering the poly tank I was concerned it wouldn't be able to hold the pressure, so I conducted a small test. The test involves an innocent mobile1 container, a tire valve, and an air compressor. I drilled a hole in the cap and threaded a tire valve into it. I slowly increased the pressure checking each time with a tire gauge how much pressure was in the container. I got to 15 psi and took a 5 minute break to prepare myself for a loud BOOM, and maybe a slight bit of pain, as the container was definitely Ballooning. Once I got my shit together, I went ahead and upped the pressure up to 23 psi. Amazingly it held, I stopped there figuring that was enough to satisfy my curiosity. While it's not the same as the container I purchased, the plastic is much thinner with the mobile1, therefore if the cheap Mobile 1 plastic container held, I feel confident the one I got will hold even better. (which after 9 months it has proven its worth) Here is a picture of the mobile1 container with 23 psi in it. http://i10.photobucket.com/albums/a1...n/Image027.jpg When I first hooked the water injection up, I used a clear poly irrigation hose. I wasn't sure how it would hold up against the heat, but no one in town had any silicone hose. I drilled and tapped the turbo for a hose barb fitting and ran a hose to the tank which was drilled and tapped on top and bottom. As it turned out the hose on the turbo didn't hold up, and I replaced it with a fuel injection hose. I also originally mounted the nozzle inside the air filter and had it pointed directly at the turbo. I had to weld a stainless steel bolt onto the back of the nozzle (see first pic below), drill a hole in the filter and bolt it to the filter. It worked extremely well like this, but I later decided to add a cold air intake to my turbo and had to remove the nozzle from the air filter and mount it to the side of the CAI. I'll post the pics of how it was hooked up originally, then post how it's hooked up now while explaining the reasons for changes. Pics of the system not installed, you can get an idea of the parts and basic system. http://i10.photobucket.com/albums/a1...h_CIMG0773.jpg http://i10.photobucket.com/albums/a1...h_CIMG0775.jpg http://i10.photobucket.com/albums/a1...h_CIMG0778.jpg http://i10.photobucket.com/albums/a1...h_CIMG0777.jpg http://i10.photobucket.com/albums/a1...h_CIMG0772.jpg http://i10.photobucket.com/albums/a1...h_CIMG0789.jpg http://i10.photobucket.com/albums/a1...h_CIMG0779.jpg |
Here is a video of the system being tested with an air compressor, you can see how fine the mist of water is. Click to play in photobucket. It's crappy quality but a cool lil video.
http://i10.photobucket.com/albums/a1...h_Video003.jpg Here are some pics of when it was first installed. As you can see there is "T" on the top if the tank. The air came from the turbo, to the T, into one side of the nozzle and to the tank to pressurize it. I later removed the T because I found a 5 psi pressure drop in the tank with the T in place. The red hose goes to the pressure switch out of view. http://i10.photobucket.com/albums/a1...n/CIMG0958.jpg http://i10.photobucket.com/albums/a1...n/CIMG0956.jpg http://i10.photobucket.com/albums/a1...n/CIMG0954.jpg http://i10.photobucket.com/albums/a1...n/CIMG0953.jpg http://i10.photobucket.com/albums/a1...n/CIMG0952.jpg |
Here are some more recent pictures after making a few changes. As mentioned I removed the T so the turbo feeds directly into the tank, the air port on the atomizing nozzle is now tapped after the intercooler on the elbow. I tapped a new hole in the tank for the pressure switch. All the lines have been replaced with silicone, except the one on the turbo is still fuel injector line. I changed the injecting point from 3 psi to 8 psi which drastically lowered my water usage. I used to run out of water in under 20 mins of hard street driving, now it lasts several trips out. Drilled the nozzle to flow more water, I tested the new flow by setting my air compressor to 20 psi and allowing the water to flow into a measuring container for 1 minute.(500cc/min @20psi)I'm using a pretty trick fuel filter I picked up at Walmart for $10 dollars, it filters the water nicely and is serviceable for cleaning. In the last picture my tank has been moved more to the driver's side. I did this when I relocated my battery to the storage container. I plan on replacing the curved boost pipe with a straight pipe now that I have room. That's about it. Been working flawlessly for nearly a year at over 500 rwhp.
http://i10.photobucket.com/albums/a1...n/CIMG1257.jpg http://i10.photobucket.com/albums/a1...n/CIMG1258.jpg http://i10.photobucket.com/albums/a1...n/CIMG1260.jpg http://i10.photobucket.com/albums/a1...n/CIMG1261.jpg http://i10.photobucket.com/albums/a1...n/CIMG1262.jpg http://i10.photobucket.com/albums/a1...n/DSC00418.jpg |
My old turbo 1400cc kaw motorcycle has a SS water tank made into the sheetmetal work on the side of the rigid frame .The turbo pressurizes the tank and a pressure valve set at 8lbs lets the water go to a jet in the carb .The carb is suckthrough to a rayjay turbo. I built this bike in 1980 so the idea is not new.I still have the bike
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Where could I find a pressure valve like that? I would prefer to eliminate all electric components. Does the valve crack open at lower pressures and then fully open by 8 psi or just what?
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Long ago I was a MR TURBO dealer and it was a part that they sold .It is tube shape and fit in the line,hose,from the tank to the carb .I will look for the old catalogs,or check out the part on the bike and see how it is made .
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Mr Turbo was a manufacture of turbo kits .The part in question had a screw to adjust the spring pressure . I will check on it for you .
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Alright cool. That would be great.
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the check valve with the adjustable head pressure would be perfect for making your setup completely mechanical.
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Both of them are adjustable. I ordered the second one cause it's under $10 with shipping. The first one is like $80. We'll see how it works.
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Something like that ,the first one. Looks like you are on your way to a mechanical system .The more pressure the more flow the way to go .
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I agree, simple yet effective. The boost switch and solenoid have been very reliable, but fully mechanical would be even better. Provided it flows the same, and holds up without getting stuck closed.
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Since you've already had it set up in a "flow test bed" once, you could do the exact same thing with the check valve in place. then you could see how much flow you are getting after the mod compared to before hand.
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I thought about pre-turbo H2O injection before.. until last night when I met a guy from AUS who said I should be careful.. He said if the system doesn't work properly and larger water droplets form, it could be detrimental to your turbo when its spinning at 100K. That made me question about pre-turbo water injection... and how fine of a mist these jets create..
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The pressure valve came in today it looks like it will do the job. I plan to get some fittings and flow test it after it stops raining and clears up over here.
You definitely need a well atomized nozzles for the turbo's sake, but there are guys that have been running preturbo for years without issue. I'm going on a year myself, and my turbo shows no signs of problems. There was even a factory turbo charged car i believe in the 80's that ran preturbo with a very basic water nozzle. The errosion they had with the old technology was minimal and on high mileage cars, it was also commented that it didnt seem to effect the turbo opperation. Not that i would want erosion in any case, but like anything it just has to be done correctly. |
im assuming your taking into account the mechanical pressure reduction of the spring valve? I.E. set to open at 8psi means it must first over come at least 8psi to open if your feeding 20psi to it post valve you will only have 12psi... just curious i really want to do the mechanical pre-turbo injection but one thing at a time.
z |
Yeah i thought about that. I wasn't sure if the spring pressure would reduce the pressure by the same amount. I haven't mounted the spring valve, when i do i'll probably test the water output. I might have to drill the nozzle out to maintain the same flow, unfortunately the atomization wouldn't be as good. Im on the fense on the advantages and disadvantages of adding the spring valve. I'm thinking a vacuum/boost activated mechanical valve would be even better. If i could find one.
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Just get one that is set at 3psi. You can always run a 'slightly' larger nozzle to overcome the loss of volume from the 3 psi pressure drop.
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I'm considering that option too, I used to have my solenoid set at 3 psi, but it went through so much more water compared to being set at 8 psi. I would definitely need a larger tank for that, but I do have the room now that the battery is in the bins. The valve I have now is preset at 5 psi but I can turn it down to 3. Flow difference would be 425cc vs 500cc with a 3 psi decrease. I can always drill the nozzle a little to make up for that.
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has anyone done this to a set of BNRs or stock twins? probably not a "mainstream" idea, but I really like the twins setup.
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Someone was going to try it using 2 nozzles for twins, I'm not sure if he completed it yet or not but I know he started on it.
You're first option is to run 2 nozzles. One for each turbo. If you're running sequential you will want one of the nozzles to come on at a preset boost level, and the other nozzle to come on when the second turbo is activated. This could be done by adding an rpm switch. I'm sure there would also be a way to tie into the sequential system somewhere to have it activate the second nozzle. You're next option is to run an airbox that both turbos draw air from. Have only one nozzle mounted on the box so that it sprays right between where the 2 turbos draw air from. Each turbo will draw in however much water they need based on their required air supply. |
Heres a diagram I made that helps show the operation of my system.
http://i10.photobucket.com/albums/a145/dudemaaan/wi.jpg |
hey dudeman I just got the nozzle and wanted to know what drill bit you used and did you drill both parts of the nozzle tip?
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I only drilled the center part of the nozzle for the water. I used about 4 drill bits and gradually went up in size. Did it all by hand cause they are so small i didnt want them to break off in the tip.i bought a set of like 10 bits. The largest size you need is just under 1mm. So if you get a set of 1 mm and under you should be good.
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Hey Dudemaaan curious to know what kind of ignition system are you running? Sorry if you had already posted it on here but I just became a member and thought I might just ask. Also what kind of power are you putting down? I'm running a GT45 turbo on my 13bt S4 motor and wanted to see what I can expect from my setup.
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I'm running an HKS twin power with stock coils, 10 mm wires, and greddy race plugs (rebadged ngk 7420's) heat range 10.
If I was redoing the ignition from stock I would go with a Crane Hi6 and LX92 on each leading plug, and stock coils for the trailing. The twin power does work very well for my needs so I won't be changing it out anytime soon. I haven't been on a dyno yet but I expect over 500 RWHP. If I was to guess I would say 530 or so, maybe more. I also have a very large street port so that will play a big roll in what you can expect. There's another guy on ausrotary with a similar setup to yours, gt45 on a 13 bt extended port, he made 530 on a street tune and then made 550 after dyno tuning, this was at 25psi. He's going back soon and trying to break 600 with 30 psi. |
Well as far as ignition I will be running the accel 300+ ignition boxes with the stock coils for now and next on the list are the greddy plugs. The ignition on the car now is factory and I know it won't keep up with the boost and water combo as the car feels kind of sluggish up top on boost at say 15psi. My logged IAT is around 200 deg. farenheit and that's running the coolingmist kit. Not happy with it right now. I want to at least break the 11's in the quarter with at least 400-450 hp.
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What ecu are you running and how much water with the cooling mist kit? And yes those IAT's are outrageous. Dangerous even. What do you have for an intercooler?
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I'm running the Megasquirt Ecu and I had the coolinmist almost maxed out on the progressive controller. As far as intercooler this is a 1st gen rx7 so no intercooler just straight from turbo to throttlebody.
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Oh thats why your temps are so high. I would try to find room for an intercooler or plan on running meth, either straight or in a mix. You might be able to get the temps down more with enough water, but it's going to take a lot. What size jet comes with the cooling mist?
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and also I was able to bring the IAT down to about 185 deg.F but still not happy with it and that was only one time.
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the intercooler is a no go. I'm on a tight budget and no job at the moment. as far as the jet I think the kit comes with a 350cc and a 550cc. I have a 550cc post turbo.
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I'm running a cheap ebay core 24 x 14 x 3 it works extremely well. I think I did the whole intercooler and piping for under $300. You're going to be fighting those air temps with water only, especially if you want to run some big boost through it. Preturbo should help but I don't know how much. Ideally you want your intake temps closer to 120* F or lower.
If it was me I would probably start with about 1000 cc preturbo jet starting with 30/70 meth water then 50/50 if I needed more. If that still wasnt enough I would go up in jet size. |
dudemaaan have you ever had an issue with the water recondensing post turbo in the intercooler or am i worried about a moot issue for the pre-turbo water inj?
z |
Na, there is so much airflow any water that condenses back in the intercooler is going to be pushed right on through to the engine where it can work it's real magic. Whatever is happening in the intercooler works, and as a whole system it works very very well.
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