On the other hand, injecting the water before the I/C means the air going into the I/C is cooler, allowing a smaller I/C core or getting better performance from a same-size core. (I don't think water will condense at such high temps)

Also, IIRC while the water injection does help cool the charge down, its main advantage is that it acts like a buffer in the combustion chamber, slowing down flame propagation similar to how higher octane does it. I recall water injection setups for N/A cars with high compression.... (boingers)

 

I think that on a 2nd Gen it would be best to place it after the I/C. that's a great place if you want to make sure that it atomizes well. Also by installing it after, and you got a different I/C set up later in life then you could retain the stock injection point. That and the fact that the few 2nd Gens that i haven seen have it installed there. So in a way it's a proven installation point.

 

I read that you shouldn't inject the water/alcohol mixture before the turbo because this will eventually erode the blades. They (Grand National boys) recommend injecting right before the throttle body. Check out this site http://home.att.net/~stevemon/AlcoholInjMod.html

 

you just need to make sure you use pure water and methanol that has all been filtered

 

What about installing these injectors into a Greddy elbow, that is preholed for injectors?? Is this a good area to have them??

 

I posted about running 25psi with water and methanol, Itried it and it does work , the car worked totally different.I am using the AQUAMIST kit , which is the best on the market ,if you want to inject before the turbo then what ever system your'e using should have good atomisation or it would damage the compressor blades.
A word of caution though , if you are tuned for H2O , you had better not run out of it under boost!!!!.

 

I'm currently in the middle of my single turbo conversion and I'm absolutely adding a water/methanol (75% distilled water/25% methanol) injection system. I used it when I owned a grand national and wanted to push 30+ psi of boost without going to a surged fuel system to supply enough fuel to prevent KR. And as was mentioned earlier you always put the injectors after the IC before the TB (depending also on MAF/MAP locations). If you run the injectors prior, 1) it doesn't do **** since the compression of air is exothermic (gives off heat) which happens after the compressor so all you would be doing is heating air and now water at the same time reducing the oxygen rich density of the compressed charge since you put water in that space. 2) Spraying after there would already cool the dense charge which is good however the IC de-atomizes the water onto the inside fins killing its efficiency since the air running over the IC is actually cooling the already condensed water sitting inside the IC instead of the air running through it…in other words you’d be insulating the hot air from cool IC air. Guys who run water at the turbo do it to cool the compressor only, plus they have big enough turbos and ICs to where this effect is negligible.
As far as making sure you don’t run out during boost, there are systems which have alarms, monitors and even relays which you can hook up to your wastegate controller to cut power in the event you forget. These top of the line systems run up into the $1000 range but considering that’s the cost of a single low end IC its well worth it when you can go from 20psi to 25psi safely. We all know how sensitive our little rotaries are to knock don’t we?

-ed

 

Aquamist has a full line of water injection related products including level switches which can be wired to switch off boost controllers , solenoids the w.i. pump (to prevent damage ) . I had all of this but did not complete the install and took her out for a test , she ran like a mother ****** , but unknown to me the SODA bottle which I was using as a temporary tank was empty ( jet=300mi/min - soda bottle=300ml ....duh ) , now I am rebuilding and installing the full sustem - pump, water injector (controlled by the E6K) , nozzle , separate tank and safety systems ( boost controller disable on low water level with dash warning) .
you should check out the AQUANIST site , I had the SPEARCO system also and it pales in copmarison !!!.

 

im going to be running the Aquamist 2C system and have the haltech control it.

if you want one the now is the time to buy as the price goes up on them after aug 15 2002

http://www.teamfc3s.org/forum/showth...&threadid=2741

 

I have the 2s system. I use a 3 gallon fuel cell. You might want to look into that.

http://www.jegs.com/cgi-bin/ncommerc...06&prmenbr=361

Cost about $130 with install kit.

Ken

 

I always inject before the IC, infact before the compressor, IT DOES WORK. Aquamist in their instruction book say to inject before the IC to get maximum benifit in a racing application.

 

but if you inject before the ic doesnt the water condense?
im going to be running water/air ic so Im thinking of connecting my Aquamist 2C right before the TB

 

I think the operative word is "racing " , once racing there would be a constant high flow of air through the system that would keep any condensed water in motion , preventing it (water ) from " hanging up" within the piping , IC etc.

 

I got contradicting info from Aquamist.
http://www.aquamist.co.uk/rescr/rescr.html Click on fitting. and look at Q14.
I just pulled this from Aquamist site:

Q 14: Surely if the jet is placed before the intercooler it will have better cooling effects?
A: Not quite true. If the air entering the intercooler is pre-cooled, the cooling efficiency of the intercooler will drop due to the smaller temperature differentials between the ambient air and induction air within the intercooler core. Secondly, there is also a possibility that the hot air from the turbo may cause unnecessary vaporisation of the injected water thus taking up precious volume that was intended for the charge air.

 

Thank You, moespeed. Just because something works that doesn't mean that it's the best way of doing it. If you talk to any one of the engineers at Aquamist they'll back up what I mentioned earlier. If you still feel there is a better way, pick up "Engineering Heat Transfer and Thermodynamics for Internal Combustion Engines". it's available from SAE publications and was required reading for me back in grad school.

-ed

 

I figure it was something we should know.
Note:
I just wanted to point out that there may be a difference in what Aquamist is saying in its manual and what's on their site. I have no experience with this product and will not take sides on this knowledgeable debate.
Experience is a bitch.

 

Well, at the end of the day it comes down to who has "used" the system it all it's specifications.

I have used water injection for around 5 years and have experienced many different points of injection and find the best "performance" result to be pre intercooler.

I have an article from one performance car mag which showed consistent acceleration gains from injecting before the IC as apposed to injecting at the throttle body. You make up your own mind, I know what works as I have done my own experimentation to back up my own theories and it works in my case.

It's a free world, you can choose to inject the water where ever you wish, either way you will supress detonation whichever location you choose.

Do your own analytical tests and you will find which location gives best performance gains, I did, and that is why I inject at the location I do.

 

This may be taking it one step too far but...

I've heard of propane and NO2 being used together and water and NO2, but what about all three? Ive never heard of propane and water...perhap the upper reaches of 30 and maybe even 40 psi would be possible...

 

can anyone chime in on the disadvantages of water injection? it'd be interesting to read that **** that was deleted.

 

here is a pic of the Spearco water injector:

 

I posted a thread on the MR2 board about water injection recently. Thought some of you here might find the information useful as well:

Here

-- DavidV

 

It's about tuning really. You could loose power and cause porblems if you over did it.

 

it would be nice to hook that injection to a knock sensor......... inject when it detects knock and then remember that so it will inject prior to it happenenig

 

Here's a question. Has anyone who has installed water injection on a rotary and had it done properly and tuned properly ever blew his engine up because of detonation with water running properly??

Ken

 

Dave @ KDR tuned car with water.