hello,

i haven't been able to turn much information up as far as searching goes, so i figure i'd ask and see if anyone remembers any articles or posts regarding this...

running water injection on a 340whp 13b-rew no porting, low mileage, t88 single turbo kit running no OMP.

is there any hazards to worry about water injection "diluting" or "cleaning" the premix out of the combustion chamber? obviously if you are cleaning the premix out, that means less lubrication for the seals. Was just wondering if anyone has any input on this subject, as it's kind of awkward to think about, seeing as how water steam cleans things at atomization, and premix is not something you want to wash out of your motor

any input is appreciated, thank you!

 

I've never run into any problems directly attributed to that (started running water injection in 2007/8). I'd say if you're concerned than just bump up the premix ratio a little bit.

 

i'm currently at about 1oz/gal - 1.25oz/gal. What are you running for pre/gas ratio?

 

When last my car ran (oil loss led to spun bearing, doing a slow home rebuild and full engine bay revamp at home) I was running 2oz/gal due to running harder seals.

I would advise *against* running that much premix if you're on stock ignition though, I was running into issues fouling plugs because the factory coils/HKS combo wasn't enough.

 

run hks twinpower and bigger wires; my other input is that I don't plan on running an insane amount of water injection, just enough to make me "feel safe". (~130cc pre-turbo)

you think I would need to get a re-tune after an install of something to that magnitude?

 

I was also considering this kit:

Mechanical Pre-Turbo Water Injection - Wannaspeed

it avoids having to wire it into the aftermarket ECU, and is pre-turbo. Thoughts? Any input on this kit vs other leading kits?

 

What seals are you running?

 

That's what I was running, (new) factory coils and the HKS Twin Power.

I've since switched to the IGN-1A coils. There is a DAMN SEXY M&W COP setup made by a buddy of mine in Australia that I'd like to eventually get though..

Disclaimer here: I am NOT a tuner, so take that into consideration.. I'm just reasonably intelligent and I've seen my car get tuned A LOT

I believe that technically you do not need to retune if you are running 100% water, as it won't be changing the AFR and there really isn't much worry of hydro-locking a rotary.

That being said, if you inject pre-turbo you will (the goal is to) adjust the behavior of the turbo itself when it comes to how it's compressor map acts. With that in mind, you may want to re-tune just to ensure that everything is still dialed in properly.

Regarding the pre-turbo nozzle.. You want to be meticulous when it comes to nozzle placement, spray pattern, and droplet size.

Nozzle placement/spray pattern: you really want to ensure that your injectant is NOT actually spraying on the filter element. Not only will that lead to uneven/uncontrollable injection volume, but may also run the risk of saturating your air filter and having drops of water sucked into the compressor..

Droplet size: Keep in mind that your turbo compressor is spinning FAST!!! A fine mist will be good, but if you get droplets forming in the spray than you need to worry about blade pitting or damage.


I currently have an Aquamist HFS-3 (or is it HFS-5? I forget ) with Summer unit installed and plumbed in just after the IC. If/when I go pre-turbo again I'll get the kit made by RiceRacing in Australia.

 

My block is a stock mazda reman, no porting. So pure stock internals as far as seals go. I am going to assume this reman block was a fairly recent reman, so it doesn't have any like '93 status seals.

Do you have any contact information with riceracing? I actually was going to ask him about this, but I couldn't find any information apart from crazy good water injection stuff on his site. No contact information lololol.

I do plan on running pure water, this is mostly a "reliability" and safety mod, I don't plan on cranking the turbo up. I haven't looked into anything post-turbo, what are the benefits / cons to each? If I were to run pre-turbo, I'd get maybe a 3-4 inch custom aluminum piping extension to tap in a mister just before the turbo. Like I said though, I'm pretty unfamiliar with these setups, and I haven't found a ton of relevant information for what I'm looking for. ^_^

 

Yeah, Peter REALLY knows his ****, but his site is an absolute mess! You can tell that he's an engineer first, an enthusiast second, and somewhere way down the line he sells stuff

I've sent you a PM with his email address.

I would go over all that with Peter. If you approach him with a thirst for knowledge he's usually pretty good about passing on what he's learned (within reason). If you call him out he's liable to just tell you to pack sand though

 

hahahah i definitely get that vibe from his site and practicality of his posts on other forums i'd be more than happy to learn what he has to offer as far as both setups go and what my best route is. I sent him an email; thank you!

 

Yep. Seems like a smart guy. But his delivery leaves you pretty certain he's an
Unfortunately for those willing to overlook that, he's been banned from at least two forums I know of.


There is also some good info in the AI section stickys you might want to read through if you haven't already. At least for the basics if this is your first system...
https://www.rx7club.com/auxiliary-injection-173/

 

I am hesitant to run a pump-style system upon further research; I am leaning more towards the mechanical style one of the wannaspeed.com one. The only problem is making a reliable tap pre-turbo that doesn't soak the filter and won't just collect on the side of an intake pipe or something -.-

 

Any reason? I've installed over 100 aem kits and have yet to have one fail.

 

simplicity is my motivation, mostly. But mostly I just want to avoid the struggles of having to wire it into powerFC stuff as I am still unfamiliar with the setup of this car for the time being.

 

One leak anywhere in the system and the mechanical pre-turbo system fails as well. Everything has it's weak points.

 

it's not that I don't believe it won't work or will fail, it's just that this will be a first time experience for me with aux injection, and the AEM wiring looks a tad overwhelming

 

Its actually a straight forward install, just time consuming mounting the pump.

 

is there a "best practice" installation to this kit? also is this kit reliable pre-turbo? does it atomize well enough?

 

A little. But not that bad...maybe one cigar (pictures at the end of thread)---> https://www.rx7club.com/auxiliary-in...ion-fd-959565/

 

I usually mount the pump on the driver's side frame rail below the steering shaft. I used a 90 degree air drill and self tappers.