I was thinking that the best place would be in the bend of the throttle body elbow pointing directly toward the throttle plate. I have the main components coming....pump, nozzle, and boost pressure switch. I plan on tapping the windshield washer tank in front...just for simplicity and less plumbing to run.

I hear that there is a need for a check valve or solenoid befor the nozzle so water doesn't get sucked in from vacuum while cruising. I see how a solenoid wiould work...wire it so it opens at the same time the pump is triggered.

I don't understand how a check valve would work....if you can blow thru it from one side, then you can suck thru it from the other....

Someone with experience enlighten me please

First off, yea that is the best place. But make sure that it is close enough that you can get a wrench on it to tighten it!! Mine is ~6" from the TB at about 4 o'clock as you look into the elbow (DejonTool UICP).

Next, the check valve. It has a pressure in which that it opens and lets things be pushed thru. This is called the "cracking pressure." Most check valves have a very low cracking pressure, that's why this one is special (from coolingmist.com I assume?). And a check valve is a one way valve. You can blow thru it, but you can't suck thru it.

Hope this answers your questions!!

The check valve or ONE way valve is also used to prevent the air entering the water line before the WI pump starts pumping ... I'm using 1bar Aqumist check valve and the main pump starts at 1.3bar or 19 psi boost pressure.

tom04841 said:

I was thinking that the best place would be in the bend of the throttle body elbow pointing directly toward the throttle plate. I have the main components coming....pump, nozzle, and boost pressure switch. I plan on tapping the windshield washer tank in front...just for simplicity and less plumbing to run.

I hear that there is a need for a check valve or solenoid befor the nozzle so water doesn't get sucked in from vacuum while cruising. I see how a solenoid wiould work...wire it so it opens at the same time the pump is triggered.

I don't understand how a check valve would work....if you can blow thru it from one side, then you can suck thru it from the other....

Someone with experience enlighten me please

Click to expand...

Yes, unclesam099 is right. 6" from the throttle body is ideal. I just tapped my throttle body elbow so the nozzle pointed straight at the throttle plate and it works great.

About the check valve and crack pressure. . .

Many guys find that the best results are obtained when activating the water injection at 7-10 psi. This means that there is boost pushing the water/alky back to the pump through out the time the turbo is bossting up to 7+ psi. This is very bad. that means that, when activated, the pump must reprime all the water/alky lines before it can begin injecting the fluid into the aircharge stream. Time is of the essence with injecting water/alky. Locate the check valve as close to the nozzle as physically possible. Remember to have the arrow pointing toward the nozzle, of course .

You need a check valve with a significantly, relatively high "crack pressure" pressure. This will make it harder for the engine to suck it open in vacuum. Also this will make it so that a certain psi must be reached before the water/alky can press through to check valve. 5 psi was enough for me. This will keep the engine vaccume from sucking the water/alky into the intake mani at idle and light throttle. and not be too much of a restriction to maintain a healthy psi for the injection process.

4wd-Eclipse said:

The check valve or ONE way valve is also used to prevent the air entering the water line before the WI pump starts pumping ... I'm using 1bar Aqumist check valve and the main pump starts at 1.3bar or 19 psi boost pressure.

Click to expand...

! you posted just before I did...

dsm-onster...where did you get your check valve?

Mcmaster-Carr.com

They will have the specs there in the online catalog to pick the right valve. I can't remember part numbers or anything. It has been a long time. I have ahd this setup on several cars. Now my dsm .

its a ball check valve? The highest rating i found was like 3 psi....you thing that is enough? What material, and what size (1/8 , 1/4, 3/8) did you use?

1/4 inch. I think 3 psi would suffice. However, I am not on my pc so I don't have all my book marks to give you a straight answer... do more research. I also recommend using a solenoid this will give you pump the most efficiency as it will loos no pressure to crack a check valve. P/N# 7876K12 from McMaster-Carr. This is the best method and worth the $35. As my simple check valve was around $20 and doesn't provide the best results. I probably will be upgrading this season to this.