intercoolers and water injection

[shredder]

Hello Nicoclub,First, I'd like to say thanks to all of the knowledgeable people on this forum. I have been meticulously searching the forums for a couple months now and my CA swap is finally complete and running and it wouldn't have been possible without this forum.

Second, I have a question about a somewhat unorthodox setup. I have modest goals of 12-14psi on the CA and I am thinking of simply going without an intercooler, running a hot pipe directly to the TB and then using alcohol or water injection to cool my intake charge. I think that this would yield an extremely responsive throttle and still keep temps in check. What do you guys think? Is this possible or is the intercooler an absolute must.

[rico05]

I have no experience with this, but I wouldn't want that on my daily driver. If something went wrong with the injection system, @ 1bar, that is a LOT of knock right there. Coupled with having to fill the tank all time just sounds like a pain. I have an intercooler sprayer and it is enough of a pain to keep that filled. Sounds like a neat idea, but I wonder how practical it really is...

[boost_boy]

Hello Nicoclub,First, I'd like to say thanks to all of the knowledgeable people on this forum. I have been meticulously searching the forums for a couple months now and my CA swap is finally complete and running and it wouldn't have been possible without this forum.

Second, I have a question about a somewhat unorthodox setup. I have modest goals of 12-14psi on the CA and I am thinking of simply going without an intercooler, running a hot pipe directly to the TB and then using alcohol or water injection to cool my intake charge. I think that this would yield an extremely responsive throttle and still keep temps in check. What do you guys think? Is this possible or is the intercooler an absolute must.

Dude, I'm glad this forum has somewhat helped you in getting your swap completed, but I'm going to be real with you, don't play with what you're thinking of playing with. It is just too risky, especially for everyday driving. Go get yourself a good cheap FMIC and go this route. Allow mother nature to help keep your air charge cool. I would like to think this a very good advice as rico has given you the same, but you are free to experiment. And seeing that you live in the south, yeah---okay!

Dee

[shredder]

Thanks for the input. It is an idea I have been playing around with for some time. This car isn't a daily driver and most of the "bolt" on front mount kits that I have seen look questionable. I am going to continue doing some research though and see what I can come up with as far as temperature differences, water usage, etc. I will most likely end up with an evo or srt-4 used front mount but this is an idea I am very willing to entertain if it turns out to be feasible.

[BACARDI_DWB]

also another idea that i am going to do (since intercoolers don't look good on 510's) is an air to water intercooler. something to concider. they are decently cheap and when you look at it its pretty simple. yes its a little more weight. but all the drag cars that are on turbo use it cause you don't have to deal with as much heat soak on a hot day. your variable are immensly lower without having to think about humidity other than what is coming in the intake. just another option for you to think about that most people overlook

[float_6969]

Answer to original question: You can run water injection only up to about 7psi. After that, pre-cooling (generally via an air-to-air or air-to-water intercooler) is reccomended as the amount of water required to keep the intake temps down becomes more difficult to inject.

Air to air is generally used on street setups because it is the least complicated, weighs the least, and the least prone to heatsoak. Also, when an air to air intercooler DOES heatsoak, it is able to deal with that heat much faster than an air-to-water system.

An air-to-water system has the POTENTIAL for over 100% effeciency in a respectively more compact design. The drawback to it is that in a daily driven situation, heatsoaking of the intercooler is almost impossible to avoid. Be it either from stopped traffic or driving the car and parking it. Once an air-to-water intercooler has heatsoaked it takes MUCH longer to get the intake temps back down to ambient.

Regardless, either system has the ability for 85% effeciency pretty easily. (That is an average number that I'm remembering off the top of my head. Don't quote me on it please) Meeting or exceeding 100% is hard to do in a daily situation with either system by itself. In a drag race situation, the ability to chill the water to near or below freezing temps allows 100%+ (I've seen upwards of 150%) effeciency. The problem is that the heat that the water absorbs eventually has to be dealt with. Trying to get an air-to-air intercooler to reach those kinds of effeciencys requires LARGE intercoolers that take up a lot of space, require LOTS of extra piping, and still may not reach 100% effeciency. You can use an intercooler sprayer, but for the same water consumption, you could inject it directly into the intake air and have a much more effecient system, though it will cost more.

My vote, and what I'm planning on, is a moderatly sized intercooler, placed in such a manner as to minimize piping as much as possible. Then continue to decrease the intake temps down to ambient. It would even be possible to bring the intake temps to BELOW ambient (considerabally below) by simply chilling the water like you would in a water-to-air intercooler.

[BACARDI_DWB]

float you are perfectly right. but of course on the air to water intercooler you can add cooling devices and cooling fins and 2 tanks but you are right heat soak is a hard one to avoid. i am going this route cause i am not doing a daily driver but i am also adding in functions like that secondary tank and coolers and ice for when i go to the track (for which my car is being built for) and there is always that double up system. one small side mount and on the other side use the water. but then you start seeing alot more weight in the car. and i am a firm believer in lightweight-power. so to each his own. and at this point i am still on the fence about air to water and air to air just for the factor of weight.

water,tanks,pump=heavy air to air intercooler=light

so i will have alot to concider soon. but float is right on the point where its up to you and your application..