shelleys_man_06

Has anyone ever heard of ERL? They manufacture water injection systems for mostly turbocharged cars. Suppose I have a high compression 13B-MSP. Would water injection be useful for such an application? I am aware that the ERL systems are mostly for spraying the intake charge before the turbo (quote me if I'm wrong), which helps cool it, therefore making it denser. They also have intercooler sprayers to aid in the heat rejection process. Back to my example, I would assume my high compression 13B would enjoy a cooler, denser intake charge. What kind of effect i.e. power, torque, efficiency, etc. would water injection have on a naturally aspirated engine? Are there any drawbacks to water injection, other than the possibility of being disqualified from certain racing venues because of dripping water? Suppose I have a turbocharged 13B engine with about 360+ rwhp, and the engine mostly saw street use. Is it appropriate to incorporate water injection, in order to keep the engine reliable? My focus is not only power, but driveability and reliability. Also, would adding water injection to such a device (360+ rwhp 13B, turbocharged) actually hurt its street performance? I have read that the nozzle[s] should be placed 5-10 inches from the turbo inlet, which makes sense. I am only concentrating on water injection in general, not compression ratio, turbo specifications, etc. Tell me what you guys think.

rotarygod

Water injection is primarily used to cool down the intake charge on forced induction. Remember the air gets really hot when compressed. On a naturally aspirated car you have ambient temperature air entering the engine. Unless you fill up the water injection tank with ice water, you are also injecting ambient temperature water into the engine as well. There would still be some heat rejection due to evaporative cooling effects of the water but little to no benefit as far as a noticable gain in this scenario. It is best left to forced induction as it does make a noticable gain there.

Another thing to consider about water injection is that it only lasts as long as the tank stays full. There are people that use it on street cars but in my opinion the are nuts. It is best to leave it for the drag strip where you need to do everything you can to get every last little bit of power out of the engine. Remember when the water runs out, it will be at full throttle. I personally don't want my insurance to run out immediately before a potential wreck occurs. When the water runs out, you usually have instant detonation. Not a very safe way to do things in my opinion.

It can work very well but keep it for drag racing and only with forced induction. If you get a nonturbo engine to the point where you need to use it, you've done some other things wrong.

shelleys_man_06

Interesting. Thank you rotarygod. But, apparently people like ERL have "street" water injection systems available. Why? Is there any way to be able to control the nozzle[s] with a supposed water injection system? For example, I hear the EVO 8 has an intercooler sprayer. Assuming that the the I/C nozzle[s] is controllable, does that make it useful on the street? So, I guess it is one's preference whether to employ water injection or not on turbocharged cars. Also, thank you for clearing up the high compression question.

rotarygod

Don't get water injection confused with water cooling of an intercooler through a sprayer. Spraying the intercooler down will just help it cool the air better. You don't need it to have a reliably running detonation free car. When the water runs out, it just runs out. On water injection, most of these people are using it because they have other issues. Generally they can't hit the power levels they want without water injection so their engines are running on the ragged edge of detonation. If the water runs out, boom! Some people run water injection on the street only for racing rather than to make higher boost levels work. In this street application they are getting a benefit from cooler combustion temperatures. If the water runs out the benefit is gone but the engine isn't. It really depends on how you use it. Since we don't condone street racing here we aren't recommending that it be used for street racing. It would be best kept for the drag strip.

shelleys_man_06

I am aware of water injection systems and I/C sprayers not being similar to each other. Okay, so I suppose exploring water injection is not such a good idea for street use. Besides, all stock engines have an adequate cooling system. Over-engineering can be a bad thing too. Thanks rotarygod.