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Old 03-25-2009, 11:46 PM   #1
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Default WI build planning

I am about to put my turbo on, and this is what it's compressor flow map looks like:

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It is a "little baby" turbo. An IHI RHB5, that was the original turbo in the old BEGi kits.

As you can see, I'll be really pushing it to hit 10psi. Therein lies the problem. I've got an MS standalone setup, and 460cc injectors, so nothing should hold me back, and I really want to be around 200-220hp.

So I'll do what us guys have always done, find ways to improvise when perceived size isn't enough.

I am trying to fill in where the compressor leaves off. Especially above 5K rpm where this compressor will fall flat on it's face.

Enter WAR EMERGENCY POWER, or water injection.

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These parts came in from cardriverx today. Includes pump, a Y and two fittings, a solenoid, and an injector.

I plan to do something like Joe Perez's setup, but probably not as involved.

As MagnaMX-5 recently put it, WI is scale-able.

(I think he actually said: "You can do a big setup, or a little setup, boiled setup, grilled setup, fried setup...)

I want to just deal with water, unless I start sourcing a good meth mix.

Either way I'll start with water.

I do want to do table switching.

I've been trying to read up, but just got into this, and worked a lot over spring break, so please correct me where I'm off base. I honestly have nearly no idea what I'm getting into, just that it will kick ***.

I want to run a pressure switch that turns pump on at 5psi, and another switch in the water line that tells MS to swap to a more aggressive timing table.

I don't plan on it being progressive or upping boost (can't do) when WI hits.

I'm not sure how to do this with MS, or if I'll even be able to use existing circuitry. The rest should be pretty simple.

What I know I need so far:

Water lines

Pressure sensors

Any help and guidance appreciated.
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Old 03-26-2009, 03:02 AM   #2
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Old 03-27-2009, 09:22 AM   #3
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Good info.

I will get my pressure switches from DO, but am trying to forgo a controller.

I just want a simple switch-on setup. I understand this will taper off the effect as fuel mass into motor increases with RPM while water mass will be constant, but I could upgrade to a controller later.
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Old 04-05-2009, 05:10 PM   #4
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the lines are available at any hardware store man and you can get more switches from ebay. Overall i think your map switching idea is kinda silly but whatever I would tune the timing right and then i would have the switch triger a change in the boost cut seting to say 6 psi etc. If you wanted to do something of the sort but the switches dont fail. And i think u are just plain worrying to much.
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Old 04-06-2009, 11:12 AM   #5
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Well I'll stop worrying then.

I honestly like your idea of just having an aggressive timing map to begin with, and a failsafe for the WI, like some kind of boost cut out.

I'm really wondering which would be more of a hassle, safer, etc.

If the table switching involves cracking open my controller, I'm not doing it, would rather do external CYAs.
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Old 04-06-2009, 12:06 PM   #6
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i just did my meth set up from AIS and on a 80* day my AIT got to 107 deg, with out meth .. with 80% water and 20% meth my ait went down to 78*. my car ran so hard all the way to red line. no knock, i was so happy to see that **** worked like they said. all this was at 11.5 psi. cant wait to go to the dyno and tune this thing.
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Old 04-06-2009, 12:25 PM   #7
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I just finished my WI install yesterday. I started with a Devil's Own Stage I kit. But I have an arming switch in the cockpit that sends power to the pump relay (coil side). The arming signal is 12V that is in series with a tank float switch (washer fluid bottle) and a manifold pressure switch. So, when the arming switch is on, and there is fluid int he tank, and the boost pressure exceeds the threshold (mine is set at ~ 10 psi) tie WI comes on. Pretty standard.

The part I am doing differently is the failsafe switch in the high-side fluid flow of the pump. I am running a two-stage boost setup. When the WI arm switch is off, the EBC will keep boost at about 12-13 psi. When the WI arm switch is on, and the WI pump pressurizes the system, a pressure switch installed just before the nozzle will close to ground, shorting the EBC control to ground, and a parallel MBC (set for 18-20 psi) will take over. That way, if there is no WI pressure, the higher boost level will not activate.
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Old 04-21-2009, 10:56 AM   #8
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~zxtex~ can I see your setup in person sometime?
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