2 stage injection

[TerryG]

Have a 350 vortec in my GMC 98 truck with a Whipple sc. Wanting to up my boost to around 10 psi. Will be using an Aquamist system. Would like to inject before and after the sc unit. Question is can an Aquamist system be modified to run two nozzles at different boost levels? i.e. before blower to begin spraying at 3 psi and after at about 5 psi. Thanks

[Forum Admin]

In order to do a two stage system with an aquamist you would need to use a control on each line to the jets. There are a number of ways this could be done depending on which Aquamist system you were looking at?

[TerryG]

most likely going with the 2d system

[Forum Admin]

Well there are a couple routes you could go.

The first and easiest (more costly) would be to have a seperate boost trigger, fia2 and hsv for each "stage".

The second would be to have a solenoid valve on the lower boost trigger jet - this would be a steady rate jet and would flow its max amount for the size of the jet and pressure of the pump. The manifold pressure switch would keep the pressure on this first stage. The existing 2d components would then be used to control the flow of your second stage. The fia2 diagnositics would not respond well to this set up and likely give you false fault signals. I suppose you could also do it the opposite way with the fia2 driving the lower boost jet and an open/close solenoid on a second jet.

I am not sure that either of these would be especially beneficial to be honest, relative to using the 2d to drive two jets. The fuel injection reference will keep the flow at the appropriate level to the load.

Be sure to use check valves on any jets that are post throttle body.

[TerryG]

if not recommending use of a 2d system, then which one? and which additional parts? Do like the feature of the blocked jet sensor on some models. Can this be added to a 1s System?

[Forum Admin]

Oh I would recommend the 2d. I was saying that I don't know that there would be any benefit from using a dual boost staged system when you have the ability to maintain a water to fuel ratio to load through the 2d.

I don't think there is any variable flow system that would be well suited to dual stages without doubling all the components except perhaps the pump.

[Brad]

On the Whipple surpercharger your idea of doing both is good. The Whipple seems to heat the air more that most units of its type. When using water on that type of supercharger the most common problem to cure is the transition from closed to open throttle. While cruisning the temperature of the supercharger seems to raise quit a bit and when the throttle is first opened the first air is super heated.
Using a system that has pressure in the line ready to use is the first step.
A fixed rate jet that comes on at 1psi or less at the charger inlet will help remove that built up heat. A jet system after the supercharger delivering water at a proportional rate would be correct.
The constant flow jet will most likely be a 0.5 to 0.8. The one connected to the high speed valve may be a 1.0 or two 0.8.
Does any one know the turbo discharge temperature?
I would assume we are looking a 350hp+. This will take a good amount of water at full throttle.

[TerryG]

These units do put out gobs of heat. They're famous for causing detonation. The newer units are soon to be intercooled. Like your idea of a fixed jet at 1 psi on the intake to immediately cool the unit. Can the 2d be easily modified to do this? Or is it just as easy to run another complete unit like the 1s? With each WI unit taking care of a specified task???

[Brad]

Terry, would like to know how you will use the truck. Will it have long pulls up hill with load. Or short power burst for street performance. Your engine processes at lot of air, sometimes the Aquamist pump is a little small for the application.

[TerryG]

Pretty much flat down here in Louisiana. Tow a boat a couple of times per month. And do pretty much play on the street daily.

[Brad]

Terry, The Aquamist pump with two large accumulators would support your truck for a 30sec full throttle run. The pump volume is too low for the amount your truck will be able to use with out the accumulators.
I can e-mail you a picture of the accumulators if you like.

[TerryG]

E-mail info to Captez01@aol.com. Also any diagrahm on modifying the system would greatly be appreciated. Thanks, Terry