Prophet7000

So I've be kicking around the idea of WI on my FD. Not amazingly expensive, lower intake temps, lower EGTs, keeps the engine clean - sounds like a good thing. Now what I'm curious about is WI for people like me who still have the stock ECU. I still have it, since the car is for HDPEs and it's still too much car for me at 7 psi, let alone 10 psi or above.

From what I can gather, I'm restricted to WI since AI requires changes to the fuel maps. Four main questions: (1) What kind of control system do you think would be appropriate? I was thinking boost/rpm related. Thoughts? (2) What size nozzle would be appropriate as to enact water's positive effects without effecting idle/drivability/etc? (3) Is there a company that makes a kit that would work for my purposes? (4) Would I need to modify the stock ignition system (eg Twin power) for this system?

Thanks for any responses in advance.

slo

iTrader: (1)

Its probably not helpfull in your situation, the money would probably be better spent elsewhere such as on an intercooler, as your car is essentually stock from your description.

Prophet7000

This will be in addition to a M2 large IC. I've already finished the battery relocation (Optima red top) to the passenger bin and switched to the fighter's intake in preparation.

Turblown

iTrader: (12)

Thats not true at all. I was on the dyno monday morning and the car with stock IC and water injection had lower intake temps and made more power than another car with the same mods, but a big stock mount IC...

All depends on setting things up correctly...

slo

iTrader: (1)

Right, so your thinking that this car is going to have gains from water injection with the stock ECU, which it seemed the OP was intent on keeping.

I didn't say that water injection wouldn't help unless you have an aftermarket intercooler, hell I have no intercooler and have 110 degree intake temps, I am merley saying that in the OP's situation as I read it water injection would probably be of little use, and wouldn't be first on my list.

Prophet7000

It's not, but that doesn't mean I can't do that too. Most of my mods are reliability mods (eg. downpipe, aftermarket radiator, soon to be after market IC, surge tank cover, gauges with user adjustable warning limit, aluminum AST, silicon hose, etc). So when I hear things like: "I saw an increase in compression following the 1 gallon water steam clean treatment. . ." and "a number of engines we rebuild seem to have died from over carbonization and stuck seals". I start to think. What if I could "steam clean" my engine with WI on a constant basis? It's a curious idea and I don't know of any threads that answer this specific question. Also just because I'm interested does not mean that I'm going to jump right out there and do it. I'll weigh the pros and cons once I understand the extend of work for implementation with my current setup. So let's get away from if I should do it and more towards how.

Prophet7000

Notice power gains are not on my list of reasons to do this. I have little need for increased horsepower. As I said before, the car is already way better on track than I am. For your amusement, attached is a picture of me in my FD at Rockingham Raceway in NC.

Turblown

iTrader: (12)

Without retuning anything I picked up 10awd hp on an EV0 I did a couple months ago. You will gain power if done correctly, without any retuning, stock ecu or not.
Reliability goes through the roof with water injection.

Prophet7000

Soooooo. . . .how do I do it correctly on an FD with my mods?

That's what I'm hoping.

slo

iTrader: (1)

I don't think thats going to happen in this particular situation. I can see how an evo or other turbo chargered more modern piston engine would pick up some power especially with methanol. They tend to be leaner than where they would get peak power. Thats not really the case with an FD.

Reliability is improved only in the oh **** cases. Like Oh **** I accidentlly put in 87 octane.

The biggest thing that will make or brake this descision is the rules of whatever racing the OP is doing. Water injection is not allowed in some racing.

Prophet7000

As long as they continue to allow WI in HPDEs then I am set for at least the next couple of years. I really have no intent racing my FD wheel to wheel ever. I just use track time to become a better driver.

Turblown

iTrader: (12)

I'm referring to water injection only, no methanol. I will be on the dyno again tomorrow, if I have enough time and the owner is up to I can do some back to backs, its a rotary too...

Howard Coleman

iTrader: (6)

actually it appears that alot of FD owners are wondering if, even though fairly stock, AI might help them.

given the backpressure/heat created by the stock turbosystem AI, specifically water AI would be of great help. cool and de-carbon the beast.

you have two AI options. HD or non-HD.

HD is around $700 and non HD is somewhere around half that for a kit. (of course you could DIY as a 3rd option for less)

HD-AI is offered by:

Aquamist
Coolingmist
FJO

each is a little different but employs an injector rather than a nozzle.

non-HD, the traditional AI architecture, uses a pump and nozzle and works well w water.

Aquamist
Coolingmist
Devil's Own
SnowPerformance

Coolingmist and Aquamist have been active on our forum.

BTW, i like your choice as to intercoolers and run the ASP large.

good luck,

hc

coolingmist

Let me do my best to help you. water injection + stock ecu should mean a little more power and lot more safe. In the 8 years I had my FD I had every system you can imagine put on it. Due to the small capacity of the 13B-REW its easy to make it bog or hesitate...in otherwords system choice, nozzle size is very important. A well setup system will do wonders, a poorly assembled system will be a complete pain in the ***.

Choose of RPM/Boost IMHO is a fanstastic choice. Unfortunately, kits that integrate RPM are more expensive in comparision to non RPM based kits. Our universal vari-cool with smart injection reads RPM + Boost and merges the 2 in a nice simple map. For more finetuning you can use MAP and RPM in a 8 X 8 cell. That kit works in a progressive fashion as either signal changes, so does the flow.

A progressive kit that gives more flow with more boost can also be a good choice, although it does not integrate RPM, it makes it easier to tune the amount of water you need. We have a nice tuning function on our vari-cool that allows this.

I believe what ever system you choose, I would do something that increases flow with signal as it makes it far more tuneable and easy to dial in. If you get a simple on/off kit do something that you can integrate RPM, TPS or some other singal with boost.

To sum up:

water injection=good if done right.

Prophet7000

Any thoughts as to what nozzle size would be appropriate for my set up?

coolingmist

Hi. it varies from kit to kit. For our vari-cool kits they ship with a 380 and 760CC. I would recommend the 380 in your case.

the "on/off" boost switch kits can vary, either a 250 or 380.

David

Prophet7000

It occurs to me, am I restricted to water only in my case? Can I use an appropriate ratio or injection level of meth/water that would work without a retune? And I guess the big question, would the addition of meth increase reliability or decrease carbon buildup?

coolingmist

You can try to run some meth, you will not be able to run high concentrations. The only real answer is to try it and see what happens. You may need a small nozzle if you run meth. RX-7s run pig rich so likely you can only run a small concentration (10 to 15%?). Maybe someone that has tried this can chime in. I ran 100% water on my FD.

Water will take care of any cabon over time.

Prophet7000

If that's true, I'm guessing that meth may not be worth the hassle. Now - question #4 from the first post. Ignition system. Does it need to be upgraded/changed to deal with the WI?

classicauto

iTrader: (3)

Should be fine with the amount you're spraying. I ran nearly 700CC of pure water on my FC with a stock ignition system (running on a haltech though, 4.4ms dwell at that time)

Stock NGK 9's in all holes.

Prophet7000

So to put the answers to my questions in an easy to read format:

Question (1) What kind of control system do you think would be appropriate?
Answer: While a on/off related to boost should work, a boost/rpm controlled would probably be better.


Question (2) What size nozzle would be appropriate as to enact water's positive effects without effecting idle/drivability/etc?
Answer: Probably around 380 cc/min.

Question (3): Is there a company that makes a kit that would work for my purposes?
Answer: FJO, Coolingmist, Aquamist, Devil's Own, Snow Performance, DIY

Question (4): Would I need to modify the stock ignition system (eg Twin power) for this system?
Answer: A stock ignition system in good shape should be sufficient. Though I'm sure a Twin Power wouldn't hurt.