Intercooler Water Spray ?
 

I've seen the water/nitrous/drag post and i was wondering if we cannot set up a really simple system. I've just tested a Subaru Impreza WRX STi 2005 a few hours ago and it's equipped stock with an I/C Water Spray.

This button just send water on the intercooler from outside with a small pump and water bottle exactly like the windshield washer system...

On the 944 Turbo, we could add this or (better) re-use the stock headlight washer system to send water to the intercooler.

I'm afraid of the thermal shock possible between a hot IC and the cold water... but a Subaru uses this on a stock car...

What do you think of that ?

You can do it smarter than that with a Link H2O controller... I have a autospeed kit and the Link hooked up to it, but I am changing pumps soon... will report FACTUAL DATA on it once I finish my current projects!

I like to setup the water injection inside the intake based on LOAD/BOOST/RPM (any or all).
On the intercooler I like to activate it based on intercooler temp..
With the SMT6 both can be done at the same time... SpecialTool will br trying this setup soon.

Did someone already test the water spray benefits yet ?

I mean, do you have some temperatures of the intake air with stock system, and while spraying water on the outside of the IC ?

NZ951 : Do you have a weblink for the "Link O2 controller" so i can see how it's designed ? ;)

Here it is. You can trigger the spray off MAP, RPM, or temperature! You can also control the duty cycle of the pump so the water has time to evaporate :thumbup:

I just need to find a decent / small pump that is not gravity fed.

Water on the intercooler is worth 12-15 RWHP at 325 RWHP level.

You don't need Link O2 or SMT6 to setup a waterspray system, here how I did mine:

- use the headlight washer plumbing and loop a hose around the IC ducting.
- punch a couple of nozzles through the IC ducting.
- use a Hobbs pressure switch and hook a vacum line to it.
- run a 12v wire from a switch inside the cabin and ground from the Hobbs switch to the headline washer pump.
- when waterspray switch is ON and at certain boost level or above, voila you got water spray.

But you dont get time to evaporate the water,, its just constant flow right?

You don't want too much water on the I/C. You'll get the best cooling when theres just alittle water evaporating every time. (think sweat)

correct. As you said no duty cycle fancy stuff with the factory pump.

The trick is to find the nozzle that would give you the finest mist spray.

And like anything else do you want to pay 3000% more to get 5% improvement?

Special,
how do you know it's worth that much hp?
I have a little hard time believing that.
I definitely think that an IC sprayer helps to prevent heat soak of the IC in race conditions, which keeps the hp you're supposed to have. Spraying ambient water (might actually be higher than ambient because of possible underhood heat contamination) on an almost ambient temp IC will not appreciably decrease the temperature of the IC core, which is what the charge air "wants to see" Therefore no increase in rated power.

Thomas,

Some physic nerd show me the formula once and I kind of believe him.

It's the energy exchange in the evaporation process that is the key to lowering the intake charge. It makes minute difference if you are using 30deg C water or using ice water.

Tommy - I don't bull****. I have dyno proven and datalogged every single thing that I post. Most of it, several times. :p

Well, yeah, I can see there being a little heatsoak with the IC with multiple runs in a dyno bay.
But I'd say this wouldn't be a reflection of what's happening on the open road.

Could you please specify the pump and nozzles,either part numbers or details... I already have hose at IC and switches wired ( I deleted the headlight washer ),but I'm interested to know what nozzles to use and that pressure switch arrangement.