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-   -   Who uses Water Injection? (https://www.rx7club.com/auxiliary-injection-173/who-uses-water-injection-833748/)

SirCygnus 05-18-09 10:08 PM


Originally Posted by rx72c (Post 9219279)
Move your jet to pre turbo.Post turbo is no were near as effective.

And honestly. Distilled water? are people on this forums serious?

yes. they buy the water.

i just run filtered water ( i get it for free from a buddies house. lives in a recording studio and all the cold runing water in the house is filtered, even if they water the grass. lol )

rx72c 05-19-09 05:37 AM

I use normal tap water here in aus. NO WORRIES.

speedjunkie 05-20-09 03:48 PM

I have the FJO kit and I'm in the process of installing it now, just trying to decide where to put all the components and I'm also looking for a tank to use. If anyone has any suggestions please feel free to tell me. This is going on an FD btw.

Also, a thread I started a while back with similiar information...

https://www.rx7club.com/auxiliary-injection-173/ai-setup-do-you-use-why-817631/

Dudemaaanownsanrx7 05-20-09 04:09 PM

Check out usplastics.com they have great prices on containers. Like 10 dollars for a the typical container that would come with a kit. They are very well built too, i pressurize mine to over 20 psi regularly.

classicauto 05-20-09 04:38 PM


Originally Posted by rx72c (Post 9221144)
I use normal tap water here in aus. NO WORRIES.

I use tap water as well.

The odd time if I'm gasing up and water is low, I grab a litre from the store and top off the tank though. Just a convience thing basically.

My car runs a snowperformance kit, "stage 2" :lol: progressive controller.

currently in the car is the 380cc nozzle
mounted in TB elbow inlet (FC guy here)
150psi pump, not the big daddy 220something.
pump and tank mounted under right headlight, tank is custom, ~2.2L capacity.
Tank will last approx. one tank of fuel with a heavy foot. With a light foot it obviously lasts forever HAHA

Also, like anthony I do run a mix of either meth, or washer fluid towards the colder parts of our year to avoid any icing down there.

Car made 380whp last year on a SHAT tune with a SHAT turbine and a SHAT ecu only revving to 5900RPM :lol:

The best part though, at 380whp, it made 330ft/lbs TQ. Perhaps alot had to do with the stock ports, but the water IMO is certainly raising torque. You can't compress it, so you're running slightly higher dynamic compression when its spraying.

This year after many changes - EGT's at redline (around 8K) are about 875C @ 20psi from the T04-R with the WI. I should likely switch back to my larger nozzle to control them, but haven't started tinkering yet.

SirCygnus 05-21-09 11:20 AM


Originally Posted by rx72c (Post 9219279)
Move your jet to pre turbo.Post turbo is no were near as effective.

And honestly. Distilled water? are people on this forums serious?


it is pre turbo. i just run filtered form a buddies house.


its fun.

SirCygnus 05-21-09 11:22 AM


Originally Posted by Dudemaaanownsanrx7 (Post 9225415)
Check out usplastics.com they have great prices on containers. Like 10 dollars for a the typical container that would come with a kit. They are very well built too, i pressurize mine to over 20 psi regularly.


here is the link?

http://www.usplastic.com/catalog/pro...oduct_id=14120

Dudemaaanownsanrx7 05-21-09 12:23 PM

Yes thats the link. You can get them with or without i water nipple coming off of them. I got mine without and just tapped my own fittings in there.

speedjunkie 05-21-09 11:55 PM

Thanks guys! I was looking at the site last night. I'll have to pick something up soon. Thanks again!

WLD 07 06-12-09 08:12 PM

What nozzles are the coolingmist guys running for what hp?

Dudemaaanownsanrx7 06-13-09 12:09 AM

I would say 100cc per 100 hp works out pretty well. I'm running 500cc pre turbo at around 500 hp.before that i ran 380 cc for mid 400's.

rx72c 06-14-09 06:03 PM

at 500rwhp i would be running 600cc.

I like abit extra.

GoodfellaFD3S 06-14-09 09:11 PM

I need to figure out what volume I'm injecting, I'm using an Aquamist 1S system with the 0.9mm nozzle and their old-school pump.

WaachBack 06-15-09 03:21 PM

Good info. That sounds about right. Based on this, we should establish what a/fs to tune for a certain boost increments. There are already a/f guidelines set up for non a/i pump gas boost pressures. We now need some for a/i.




Originally Posted by Dudemaaanownsanrx7 (Post 9286327)
I would say 100cc per 100 hp works out pretty well. I'm running 500cc pre turbo at around 500 hp.before that i ran 380 cc for mid 400's.


Dudemaaanownsanrx7 06-15-09 04:53 PM

I just tune about the same afr's but run higher boost. I like to keep it on the conservative side and let the boost make the power

WaachBack 06-15-09 11:46 PM

Well I mean, usually when you raise boost, you richen it up as well. Most non-a/i guys run at around 10.5-10.9 A/Fs at 15PSI. Im running 11.5ish A/Fs at the same boost pressure due to my 315cc's of water.

TweakGames 06-16-09 12:14 AM


Originally Posted by WaachBack (Post 9291733)
Well I mean, usually when you raise boost, you richen it up as well. Most non-a/i guys run at around 10.5-10.9 A/Fs at 15PSI. Im running 11.5ish A/Fs at the same boost pressure due to my 315cc's of water.

I think people run such rich AFRs to help stop or suppress predet/knock to make running pump gas at higher load pressures safe. With water, you are able to use the water to knock suppression, slow the flame front, cool the internals, and use the fuel for its power only without fuel flooding it. I read somewhere that there was a consensus that 11.9-12.1 AFRs with water was about the sweet spot or something like that.

Here it is http://www.lotustalk.com/forums/f160...ml#post1045017


Tuning and miscellaneous notes on water injection:
Always keep in mind that water injection is being used to suppress knock and permit tuning AFR to its maximum power levels. Water in excess of the amount needed for a safe knock suppression margin will hurt net output. Not leaning AFR enough or leaning it too much can result in decreased power levels.
The relationship that you should seek to manage with water injection is the ratio of water to fuel. Metered to exacting proportions as little as 3% water to fuel can replace the amount of heat absorption that fuel previously provided when leaning from 10:1 to 12:1 AFR.
I have no way of knowing if any of this is true, but is the entire thread made a lot of sense to me. Maybe this thread is widely known but yeah... Would be cool to see your guys opinions of it. :)

Also, this one is pretty interesting. http://www.max-boost.co.uk/max-boost/intake/WI.htm

TweakGames 06-16-09 12:50 AM

Opps hit post too fast.

"We've seen that excess fuel is traditionally used as in-cylinder coolant. We've also seen here that water is a much better alternative for this purpose, since its latent heat is 6 -7 times higher than fuel (energy absorbed as the tiny droplets evaporate)
Latent heat of fuel = 350KJ/kg
Latent heat of Methanol = 1109 Kg/kJ
Latent heat of water = 2256KJ/kg

It appears that all you need is 3% water/fuel to replace two points of AFR (10.5-12.5). There is no performance gains in going richer than 12.5:1, and a lot less mass of water is needed to cool things down."

(sorry if this is already well known information.)

WaachBack 06-16-09 04:17 AM

^^ Makes sense.

TweakGames 06-16-09 04:45 AM


Originally Posted by WaachBack (Post 9292147)
^^ Makes sense.

kk. :) Just trying to help and understand this stuff like everyone else. A lot of people are getting some amazing results, I can't wait to get my engine back up. (like all the people that are not running race fuel or AI of some sort lol. Although running AI or race fuel wouldn't have helped me lol)

Dudemaaanownsanrx7 06-16-09 11:30 AM


Originally Posted by WaachBack (Post 9291733)
Well I mean, usually when you raise boost, you richen it up as well. Most non-a/i guys run at around 10.5-10.9 A/Fs at 15PSI. Im running 11.5ish A/Fs at the same boost pressure due to my 315cc's of water.

Before running wi i still didn't run so rich. I ran 11.3. at 15 psi but never exceeded 16 psi. When i added the wi i left the tune the same at 15-16 psi but then later when i trusted the setup i increased boost to 20 w/ 11 flat afr. I'll probably tune to 25 psi at 10.8 or so.

rx72c 06-16-09 05:00 PM

For people using water only.

Dont go leaning it out while adding water.

Keep it rich. Have a good ignition system.
Thats the key to reliability.
Your not trying to subtract fuel for the amount of water added. This is the mistake alot of people make. ITS NOT METHANOL.

WaachBack 06-16-09 05:15 PM

Did you read the article above? Because it states you do the exact opposite and it actually makes a lot of sense.

Dudemaaanownsanrx7 06-16-09 05:46 PM


Originally Posted by rx72c (Post 9293493)
For people using water only.

Dont go leaning it out while adding water.

Keep it rich. Have a good ignition system.
Thats the key to reliability.
Your not trying to subtract fuel for the amount of water added. This is the mistake alot of people make. ITS NOT METHANOL.

I agree, while water can allow you to tune a bit leaner, the small amount of extra power isn't worth lowering the safety margin, that's one of the whole points of adding AI to the system. I like to tune to the middle/upper range of whats generally considered the limits on pump fuel alone. So if 11.5 @ 15 psi is considered the edge of being safe on 93 alone, I'll tune a a couple tenths of a point lower with water. Without water I wouldn't even attempt 20 psi, but my knock readings are right around 20 with 500cc water and 11.0:1 AFRs. I started out with around 10.5 afr, but I could feel a difference when I took some fuel out, and knock was the same so I left it there when I got to 11.0. So far I've run up to 22 psi and haven't had any issues with tuning this way.

rx72c 06-17-09 02:48 AM

WaachBack

Mate i dont care for stupid internet articles.

I have done alot of wi tuning and MY REAL LIFE experience has shown me that pulling out fuel and replacing it with water is not using the power of water correctly. And pushing the envelope you will end up with a dead engine.

Im not going to argue with you, my experience has shown me lean mixtures only net good gains with weak ignition or STUPIDLY high amounts of water. Other wise running low 11s high 10s is a good place to be.


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