My water injection plan, is it crazy?
 

So currently, I have stock twins with post turbo WI in my elbow and I'm pretty happy with it. It's a simple cooling mist setup that sprays at 7-8psi. But I've been thinking of adding pre-turbo water injection as well to increase the efficiency of the twins (BNRs in my case). So here's my plan.

-add a 3 way Tee (dunno if this exists) to my current water injection line
-add Cooling mist super atomizing nozzles as close to the primary and secondary turbo inlet as possible. Probably in the aluminum squiggly pipe for the secondary turbo and the black plastic tube for the primary.

So this much is pretty simple, but when to inject seems to be the hard part. I'm assuming I can inject into the primary turbo at the same time that the post turbo water injections starts up. The secondary turbo though I'd have to inject probably when it starts spooling up? I'll have to put in a solenoid for the secondary turbo water line and somehow send signal to it when the secondary comes online. Any thoughts would be good here.

Other things I need to consider:
-The nozzles at the turbo inlets probably shouldn't leak, bad things happen when big drops hit the compressor right?
-How much water to spray?

I've seen a few of the single turbo guys do both pre and post turbo, but I haven't seen anyone do it with twins yet. Seems like it would be pretty sweet if you can increase the efficiency using WI. It'd be like having 2 bigger twins.

I'm not sure your pump will maintain pressure to 3 nozzles.

Why would you do this if your current system worked fine?

Some think preturbo aux-injection can damage compressor blades.

Well preturbo injection makes the turbo more efficient, so more power at the same boost level, less heat, etc etc. At least that's how I understood it.

How big of a nozzle do I need for each of these?

water injection doesn't make more power.

i thought of doing this, except on a single t04z, one nozzle at the elbow and one in the turbo intake. mainly to receive the benefits that both offer, that being the the change of state of the water at the turbo preventing superheating the port turbo air, and the change of state in the combustion chamber to keep egts under control.

not too sure how it would work on a twin setup tho, would be much harder to plumb and keep constant pressure to.

I have stock twins with pre turbo and pre throttle injection. My setup is simpler, I have a tee and two lines, one goes to the nozzle in the elbow and the other one to the nozzle on the end of a dual entry KN cone filter I bought for this purpose.

https://www.rx7club.com/attachment.p...1&d=1296583008

Can you tell us what part number K&N filter you used please?

I measured the pipes in the M2 airbox (diameter, distance between them) and looked through their catalog for one that i thought would fit. I didn't find an exact one so I ordered the one that was the closest and it worked ok. Mine has a rubber top, I drilled a smaller than needed hole and the nozzle is press fit in there. I wanted a metal top one but didn't find one. I'll see if i find the part number.

http://store.knfilters.com/search/univdualtapoval.aspx

I think it's this one but I need to verify: http://store.knfilters.com/search/pr...x?Prod=RU-4710

Interesting that's pretty cool. I thought for preturbo you have to put the injector as close to the compressor wheel as possible though, so the water doesn't condense or something? Dunno.

I figure the water should be well atomized, a mist that just flows with the air and the turbos will just suck it in.

Hm that makes sense. What size is your nozzle and what do you use to trigger the spray? Boost? Or something else?

I have a progressive controller and 250psi pump from coolingmist triggered by boost. pump speed varies with boost.


180cc nozzle at the greddy elbow
350cc nozzle at the air filter pre-turbos

Please don't believe the myth that water injected pre turbo has any less effect in controlling combustion temps. If you look at the temp rise to intake and the ethalpy progression of the water at the intake temps you will be seeing most of the latent heat of vapourisation energy is still there to be absorbed, let alone the fact that temp on combustion are so much higher that even without the vapourisation transition energy the water will still be absorbing huge amounts of heat regardless. I cannot understand why people continue to speil off misinformation like that when the maths is pretty damn simple.

pre turbo water injection does not benifit besides cooling the turbo down. By throwing in water in the turbo inlet your reducing the amount of air that the turbo can inhale. but by injecting after the turbo and forcing water in after the turbo has inhaled as much air as it can this is where you benefit. pre turbo water injection does not add any power.

SilverFD, no form of water injection adds power. It all reduces power. But, preturbo injection can increase effeciency of the turbos.

Red dragon, if you are going to go pre-turbo injection, make sure that you use a solenoid on the nozzle.