BlackB18C

I just installed a Greddy turbo kit on my b18 powered civic, Right now it has no additional cooling. I've heard good things about water injection, inexpensive, stealth factor etc. Everyone knows the benefits of an intercooler. I'm seeking educated opinions from people who've had experience with one or both cooling methods. Which would you choose and why?

Stu

Well first of all, an air/water intercooler (which is what I'm assuming you meant in your title) is completely different than water injection. Water injection literly sprays water into your intake manifold to help cool down your intake charge. Water/air intercooler on the other hand is simply just like a radiator.

The short answer is this:
With a standard air/air intercooler, at 100% efficiency (which is as high as it goes) means that it can cool your intake charge down to whatever temperature it is outside. Why? Because you are using air as the medium for taking away the heat from the turbo. And as logic would tell you, air has a specific heat capacity (meaning that it can only hold so much heat) the same as, well air, which is coming from the turbo, so you can only get as cold as the air that is taking the heat away.

Now, a water/air intercooler can reach temperature lower that the air outside becuase water has a much higher heat capacity than air. (it can absorb more heat, especially if you use ice water)

If you want the simplest and most reliable set-up, (reliability refers to the intercooler, not the motor) then an air/air is the way to go. If you want the coolest charge possible and are okay with dealing with water pumps and stuff, then water/air is the way to go. And finally, here are some pros and cons:
air/air:
Pros--> Easy to use, cheap, reliable, simple.
Cons--> Must have good airlfow in order to function properly and avoid heat soak.

water/air:
Pros--> Can operate at better than 100% effeciency, much smaller, doesn't need to be in direct airflow, more options for mounting due to the size and airflow issues.
Cons--> More complex, may have to deal with different kinds of pumps for different driving styles applications.


I hope that helped.

Oh and by the way, I personally feel that water injection should only be used when you have already reached the peak of your current systems effeciency and still need to boost more. It should not be used as a band-aid for bad tuning.

Full-Race Javier

IMO,
air/air on a street/daily driven car
air/water on a track/race car

BlackB18C

Thanks stu, that's helpful. I was referring to water injection, I know it's commonly used on jackson chargers, and a friend of mine with a turbo mr2 swears water injection is the way to go. I helped dyno another friends Jackson blown gsr which showed a 30 hp increase on the dyno when we used water injection. I know air/air intercoolers show large increases as well. That's about the extent of my knowledge which is why asked in the first place. thanks for your response

Armed Ferret

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlackB18C &raquo;</TD></TR><TR><TD CLASS="quote">a friend of mine with a turbo mr2 swears water injection is the way to go. I helped dyno another friends Jackson blown gsr which showed a 30 hp increase on the dyno when we used water injection. </TD></TR></TABLE>


turbo mr2--very difficult to get a LOT of necessary airflow to an air-air intercooler without at least mid-level bodywork, hence the great platform for either water injection or water-air intercoolers. (this is, of course, keeping in mind the more budget-oriented mr2 as opposed to porsche's success with air-cooled turbos, which were/are far from budget-oriented. )

danl

A good FMIC and charge system is IMO better than water injection. HOwever when relying on the stock or unsufficently designed charge system on a car that is flowing much more air water injection seems to work well. I use it on my eclipse and yes I do run much more boost and make more power. HOwever, I think the water would just "load up" my engine if I installed proper charge pipes and intercooler.

Water injection is also more complicated, and you better make sure its working properly if you're boosting.