Looking Into water injection few questions
 

Well with the hot summer temperatures my intercooler does not seem to provide the low intake temperatures I was hoping, I do not want to install a bigger intercooler and restrict radiator flow any more.

I am mainly looking into water injection to lower intake temperatures and as a safe guard. I want to buy a base bone devilsown water injection kit and set the water injection to start at about 8 pounds. I have a hybrid turbo running 14 pounds on a streetported s5 engine running haltech e6x with 9.0 rotors.

My questions(sorry if these are stupid I have researched for several days and still seem clueless)

-For my purposes straight water is possible, correct? (seems stupid but all anyone talks about is alcohol)

-For my purposes would a simple boost switch with one nozzle after 8 pounds work and a 7 gph nozzle?

-Does water injection have any negative affect on premix? because I would wonder if water during combustion would dilute the premix. I doubt this would cause any problems but figured I would ask.

-How far after the FMIC should a nozzle be installed?


Hopefully none of these questions are repetitive, I just want to clarify before I invest money. Thanks

Straight water will be fine. You should do a bit more research on the cooling ability of water though. We use alcohol because of the cooling. Water is better for preventing detonation. It certainly won't hurt you to run water.

Setups with a boost/hobbs switch have been run successfully for years. It should be fine, but you will probably want to be able to tune it later. Depending on what the CFM is of your turbo at 14lbs, a 7gph nozzle may be too big. Get a couple few sizes and test them.

That is a good question. I don't believe there would be an issue. The water vaporizes in the combustion chamber and is swept away with the exhaust gases.

There is debate as to where the best position is. Some run the jets pre-compressor, some shortly after the intercooler, some near the throttle body, and some direct port. Mine is just upstream of the throttle body as I'd prefer to avoid any pooling occuring from a long path to the engine. I would do direct port if I had a HSV setup, but my current jet setup doesn't have the exact control I'd prefer for that. My injection point is about 12" before the throttle body.

Josh

I plan on a similar setup for very similar reasons (intake temsp keep climbing during 20-30 minute track sessions)

An option, which I plan to use, is to run the system from your windshield washer tank. Then just run the good-ol blue stuff thru it. It's a water/alcohol mix which works surprisingly well for lowering temps and reducing detonation. Plus it's already mounted in your engine bay.

Sounds great, I am really thinking I am going with Devil Own stage 1 kit. And run just water to start and after I get that working move on to 50/50 and tune a little.

I have had a idea and does not know if it makes sense. What if I purchased an additional boost switch and have the first switch turn on at 5 pounds but have a resistor wired in to the pump does not run full power, then after 10 pounds the second switch turns on and supplies the pump with full power so it pumps more water.

Switches cost about 15 bucks and a stage 2 is another one hundred and this would seem to work

A snowperformance system will do just what you mention and you'll be able to dial in the turn on and max spray points instead of buying other switches to change them.

The switches would work though, it would just be a matter of doing your own tiral and error which in some cases is more expensive then buying a proven system.

IMO, for cooling and some knock protection you can't beat straight water. Running booze will richen the tune since the alcohol will burn like gasoline. Granted, it does cool well and has other upsides, but IMHO for the purposes of spraying on top of an exisiting tune for the purposes of cooling and a little knock protection - water is the ticket.

I inject about 4" pre throttle plates. Straight water, 325cc/min nozzle, 20C intake temps at full boost (14psi from a GT35R) turn on is 4 psi full spray at 12psi.

Wow that is really low IAT mine is at about 100 degrees at full boost on hybrid turbo. I am for sure getting water. Is there any reason to run distilled over tap?

I usually just buy a big bottle of whatever bottled water the ysell at the gas station. I'm sure you *could* run tap water, but for the sake of not getting crap in my motor (only filter is a screen behind the nozzle) I'll just run evian/dasani/nestle/whatever :)

Also, my IAT will creep upwards if you boost long enough, but I've never seen it above 28C after some long hard beatings. It just drops to twenty shortly after the spray comes on.......