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Water injection adds a safety factor to any turbo system. If you just add water injection without the JWT program you will lose power. JWT sets the water injection just like they set up their NOS systems. So when the water injection kicks on, the fuel and timing maps change as well. With water injection Mike Kojima was able to get 272hp on pump gas with my car (long time ago) and around 240hp without. The water acts like an octane booster sorta.

So to answer your question, yes, water injection will help even with a T25. In fact, since a stock T25 off a SR20DET is not that effiecient, water will add more reliablity to your car.
 

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Absolutely Correct

A system utilizing a T25 would probably benefit more from H20 inj than a T3/T4 simply because at the higher boost ranges the 25 whips the air harder and creates more heat than some of the more efficient larger snails.

I have an article on water injection from a rag (Zoom Magazine) from AU. Haven't had time to post it. I'll try to put it up in the next day or so and I'll add the URL here.
 

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Cool. Didn't expect this in depth of info. Excellent guys :)

How much is a water injection system minus the cost of the JWT ECU upgrade? I know nothing about what the system consists of (other than a water tank, hoses, and jets of some sort), so can someone describe what a system includes? Maybe someone has a link to some pictures somewhere?

Another question- why use water injection vs. N2O for the same purposes? What are the differences? Pros and cons?
 

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water injection is not a power adder, it just helps the turbo work more efficiently, like an extra intercooler, makes the air more dense and cooler. n2o makes power and is ALOT colder than water.
 

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I know Jay runs it to defer detonation because he still has the stock 9.5:1 compression ratio. As a lot of you know I will be adding a T25 to my car fairly soon and plan to keep the stock compression ratio as well. Can I put out enough power with the T25 to necessitate water injection? About where is this threshold? How can you tell if you really need it or not? If I have a great IC and all the other goodies (boost controller like Mike Gosselin's, 3" downpipe and exhaust, good mandrel turbo piping, etc), will I need to graduate to water injection at some point? Or will a high-quality IC take care of that enough with the "lesser" T25 as opposed to a T3/T04E like Jay has?
 

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Well shoot me if im wrong but doesnt it also increase the compression ever so slightly also? Like on a cool humid day the car runs strong, cause the water in the air takes up more space and also is less compressable than air. I could be totaly wrong but not like this will be the first time. and it does help cool the air by evaporation, hot air+fine water mist=cooler air by the water pulling the heat aka energy from the air.
 

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Yes the water will be more beneficial on a T25 vs a To4e. The T25 is less efficient when making 12-13lbs of boost and heats the air more.

The Aquamist system is really pretty simple. A pump, pick up line tapped into the washer tank, feed line out of the pump to a "jet/nozzle" in the IC pipe. That's about it outside of wiring.

Now for a budget without a JWT h2o program, you can use the "pressure switch" they give with the kit. When it sees (I think) .8 bar boost it turns on the pump. If you are not using the ECU and will have the water flowing all the time (A washer tank lasts a long time and you have a warning light on the dash to let you know if you are low) you can run a lot more base timing, and lean it out a bit via a FPR. This will help recover some of the power the water will take away.

I would just go with the timing personally. I think you will find that with the big water jet you will be able to go up a LOT higher with the boost over no water at all. This will more than offset the "pissing on the fire" affect of water injection.

Mike said he has run 18psi in pump gas in Ryans car with a 1mm jet during a flat out high speed 5th gear run to try and induce detonation. He saw none.

I have run 17psi on pump gas with a .07mm jet but not for a top speed pull.

This of course should be done very slowly and carefully so you don't blow something up.

YMMV
 

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Thanks Jay.

Ok, now to twist it a little bit. How do I "know" I'm having detonation. I remember someone saying that is Mike Jez was detonating at high speeds he wouldn't be able to hear it. I know what knocking sounds like (I've got this 4 banger 93 Pontiac 6000 I've been toying with :) ) but Mike K has probably had a laptop in the car with Ben from JWT watching the knock sensor output. (BIG question:) How do I tune my car for max power with zero detonation???
 

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well, when I first put my bottle in, it was detonating so bad you could feel the engine surge. beyond that, you would have to look at a dyno chart, and look for drops in power. waves of power loss and gain, ect. detonation is fun stuff to play around with :)
 

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You dont tune it then :D nah just kidding. Just be conservative probaly. And know what does what when you do it. Hmmmm thinking now, I have a spare laptop wonder if its possible to get a program and a port adapter to plug into the consolt port? hmmmmm intersting. might have to look into this. got a pentium 90 16 meg ram 500 meg hard drive laptop from my step moms work for 100 dollars. Not bad runs win98 decently enough to surf the web across a network at school on the eithernet. hmmmm wouldnt mind having a consolt program for a laptop and be able to see all this stuff. know they do it in other cars with even cheaper laptops cant see why i cant. may have to ask the list this one
 

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I just linked part one of the Zoom series on water injection to my site

http://homepage.mac.com/carlm/start.html

Look under articles

The series is pretty comprehensive and touches on a few things I haven't heard discussed in the Sr20 camp, including adding MeOH to the mix to get better atomization and therefore a larger "safe" range to crank up the boost.

Of course I have been off the mailing list for about a year now so I could have missed this one...

I should have all three articles in the series posted in the next few weeks.
 

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I see two Zoom articles under Articles, one is titled Zoom Magazine VL and the other Zoom Magazine 200 SXR. Am I just blind or is it not there?
 

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Hit reload on your browser.

There are three Zoom articles in that section.

The one called Zoom Water Injection just below the Road & Track Spec-R article is the one you want.
 
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Discussion Starter #14
Detonation sounds like little pebbles hitting a tin can. You have to have your windows rolled up and the stereo off to hear it. It's pretty suttle, but if you really stay into it while it's happening, you'll destroy your pistons.

Ryan
95 200SX Turbo
 

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I posted part II of the Zoom series on water injection

http://homepage.mac.com/carlm/start.html

go to Articles then Zoom water injection

I'll post the third part next week.
 

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Ok, time for more questions. JWT makes just a water injection program-add on, not a kit with nozzles and stuff, correct? What kit should I consider? Where on the net can I find info of different systems? How much are they? I know water is cheap
.

How about this: does water injection make sense with running no IC?

Will a GOOD intercooler by itself do a better job that a GOOD water injection system with the JWT module by itself? Does is make sense to run H20 injection with no IC?

Working with JWT and explaining to them my setup at length, if I have a boost controller, do you think JWT will be able to tell me "Yeah XXpsi should be very safe on XX octane of fuel running the H20 injection."

Well, I guess that statement really doesn't make sense cuz the H20 injection will kick on only at WOT? Or at a particular boost level? Basically it's nearly like NOS for a turbo car. You hit WOT and you get several tens of hp.

Can you enable/disable the JWT H20 so that you can run WOT without engaging the H20 system?

Trying to figure out if I want H20 injection and if so, when it would make the most sense to get it in my turbo upgrade scheme. After I get it installed my first upgrade will be a 3" catback. Then a Blitz boost controller since Mike G likes his so much.
Then either a high quality intercooler or H20 injection, whichever will be more cost effective and healthy for the system. Well, probably want an IC since that makes power/helps detonation all the time. Yeah, duh, hello, guess I answered my above question about whether H20 injection is better/worse that an IC.


Think that's all for now
 

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Hey thanks man. I will read up on them as well as Bubba's page finally.

How much does the JWT NOS/H2O module cost?
 

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I envy you turbo guys! I am turbo retarded. don't know much about it. I started hooking up the ride back in 91 the old fashioned hot rod style and went all out MOTOR. can't afford the ferris wheel now! oh the shame!!

[Edited by redman007 (09-25-2000 at 10:23 PM).]
 
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