Water Injection: before or after turbo???

[GeneralTJI]

Just wanted to revisit this topic for a bit:

Currently I am sprayting before the IC w/ a 720cc injector. And I am spraying after the IC with a 280-380cc injector (right around there). I tried to run a smaller injector on one of them but my pump hits some kind of high pressure shut off and it causes it to cycle on/off real fast. Something weird going on with it... any smaller nozzles than this and it isn't happy. (150psi coolingmist pump)

Anyway,

What I'm getting at is running my biggest nozzle before the IC. I read on a few injection company sites this isn't recommended. Some mentioned pooling but I'm not worried about that because I start spraying at ~20psi

But they also mentioned some other possible issues:

2 Pre-Intercooler


Pre-intercooler seems like a sensible nozzle location but, the thing to think about is if the air entering the IC is pre-cooled, the ability of the intercooler is because the temp difference is lesser. It is also possible for the fine water/alcohol mist to collect in the bottom of your intercooler core. We don't recommend this location either. The other problem is that there's a possibility that the hot air from the turbo might unnecessarily vaporize the water and take up some of the volume built up by the turbo that was supposed to be for the charge. Pre-IC does work for some track cars such as road racing that operate at a more constant higher RPM. For the daily driver, weekend racer, the pre-intercooler location should not be considered.

http://www.alcohol-injection.com/articles/where-to-locate-your-alcohol-water-injection-nozzle-2/

2. Pre-Intercooler Injection

While pre-intercooler injection may at first seem like a logical approach. Thereby, combining the effects of water methanol injection within the air-to-air intercooler for an increased synergistic effect. It is not so. Matter of fact, it's the opposite. The cooling effects and benefits offered by the water methanol injection are less when injected here then in all other locations. Further, more other issues arise such as puddling which can form in the bottom of the intercooler. Additionally, pour atomization will occur as the fluid will accumulate in the individual air to air intercooler core walls of the intercooler forming larger droplets which will eventually break away resulting in pour atomization. We do not recommend pre-intercooler injection.

http://www.alcoholinjectionsystems.com/a40/Where-Do-I-Position-My-Water-Methanol-Injection-Nozzles/article_info.html


Really like to hear what you guys think about all that?

Maybe switch and run my smaller jet before the IC?

 

[Killerbee]

This is a completely debatable subject, and one that has no definitive answer. The benefits of pre-CAC misting depend so much on CAC heatsoak condition. If the CAC has lost it's benefit (extended hi boost towing, for example), the pre-CAC misting is probably essential.

 

[GeneralTJI]

Well I dont tow often, and when I do it's usually lighter loads (4-6k) And I don't beat on it while towing.

Thinking I may switch them and see if I can detect any change.

I just don't see why injecting before the IC is going to make the IC less effective. If the air entering the IC is cooler already, of course it's not going create as much of a change between inlet and outlet temp when the difference between the two is smaller (it doesn't need too anyway to get the job done)

Now I can see where spraying into the IC could possibly have a negative effect on atomization....

 

[ChevyTruckGuy78]

and from what there saying maybee closest to the head?? like puttin in the y bridge??

 

[[email protected]]

With scr and exhaust fluid being another fluid you have to add to the engine, why hasnt there been a stock application for this especially for NOx control. It seems like if water injection works why havent we seen it on stock trucks if they are willing to make the costomer add DEF.

 

[lotsofmiles]

With scr and exhaust fluid being another fluid you have to add to the engine, why hasnt there been a stock application for this especially for NOx control. It seems like if water injection works why havent we seen it on stock trucks if they are willing to make the costomer add DEF.

I don't know much about the Exhaust Juice but I'm betting it doesn't add hp/tq

On my stock tune h20/meth added 102 hp/200+tq at the wheels.

I would think they don't want the customer under warranty adding 100 hp.

 

[JD4440]

I don't get the quoted type. How could making the air going into the intercooler less hot be bad? Seems like it'd be like adding a bigger intercooler ?