Re: HFS-4 Q&A, application for your engine...
 

Options:

1 - If the engine is direct injection, the HFS4 will be more suitable.

2 - The aquamist system can only control one channel unless you add a second valve (activated by a pressure switch)

3 - The PWM system may not require a staged injection setup as the flow is proportional to engine load rather than boost only.

4 - I need to know the engine layout before commenting on this.

Re: HFS-4 Q&A, application for your engine...
 

1 - The LS3 is not direct injection, it is normal sequential injection.

2 - Ok, thanks, so it can be done

3 - I get that, but looking at your jet flow chart the 3 jets appear to flow too much at low pressures and wouldn't atomize very well down at 20-30psi. That was why I was thinking of running a small jet for low rpm that can operate at 160psi yet still give the right amount for low rpm and then have 2 big jets for as the boost and rpm builds. Am I missing something?

4 - Engine layout - I'll see if I can upload some pics. My water/meth tank is in the trunk and the turbo is where the rear muffler would normally be, so plumbing a jet pre or post turbo would be simple.

The intake pipe smoothly routes all the way from the back into the front of the engine bay and steps up to 100mm before the throttle body. About 400mm back from the TB I have 2 water/meth jets hidden underneath, just downstream from the blow off valve.

When I'm at my work computer I'll try to upload some pics.

BTW: Lag from this rear mount? If I load the converter it will boost from a stop thanks to a 2800rpm stall converter. People get too carried away trying to set turbos too close to the engine thinking the added temp is important. It really isn't near as important as having free flowing plumbing in and out.

Re: HFS-4 Q&A, application for your engine...
 

Here is the intake on the LS1 before I got it polished. It will look the same with the new LS3 motor to go in.

The 2 water/meth jets are downstream of the blow off valve about 100mm ie. on the throttle body side of the blow off valve, and out of sight underneath.

https://lh6.googleusercontent.com/-p...o+4+inches.jpg

Here is the turbo right out the back. Since then we shifted the wategate so it vents straight to the atmosphere and gained more clearance.

https://lh5.googleusercontent.com/-z...o/P1000871.jpg

and here is the intake from the front looking back

https://lh4.googleusercontent.com/-_...o/P1000875.jpg

and the car itself, looking as close to stock as possible

https://lh3.googleusercontent.com/-0...o/P1010326.JPG

Re: HFS-4 Q&A, application for your engine...
 

In reference to needing staged jets.

The Aquamist system runs at a constant 180psi. If the parts are designed to work together then there is proper atomization even at very low flow rates. Here is a video of a system put together that flowed 3000CC at 180psi from 6 x 1.0mm jets. The system in the video is run from 100% down to 20% then back up to 100% and atomization is outstanding for the entire range. We then pulse the system to show the quick on/off capability of the system as well.

http://howertonengineering.com/2010/...-hfs-6-system/

https://www.youtube.com/watch?v=qeBw...layer_embedded

Re: HFS-4 Q&A, application for your engine...
 

I think you are confused with our "PWM valve" system to a "progressive Pump speed" system (PPS) offered by all the other manufacturers.

The inline valve system does not exhibit those non-linear delivery curve (bottom heavy) offered by the PPS system, I will try to illustrate:


As you can see, feed the same duty cycle (%DC) yielded a complete different flow curve between the systems. Your concern regarding low RPM flow is fully justified. Until you have actually used an aquamist system, you will appreciate the difference.

Your second concern on delivery latency is common to the PPS system. The delay of reaching the flow target will depend on the hose length. For a trunk mount set up, in can be up to seconds rather milliseconds compared to the PWM-valve, constant pressure setup.

Here is a chart to make it clearer.

Re: HFS-4 Q&A, application for your engine...
 

Wow, that is very impressive. I'd like to do a project like that someday on a built twin turbo LS 7 liter, but for now I'll only need 1200 cc lol

I had a look around your site - love the twin tanks with LED's.

I run a 15L tank now and it lasts me about 3 tanks of gas on average normal street/highway driving, so going down to 7.5L would require topping up every tank of gas, which could be an issue for long trips away from home. But I love the concept of not having to pre-mix and being able to pour 100% meth into one tank and filtered water into the other.

Re: HFS-4 Q&A, application for your engine...
 

Thanks Richard, I get it now. This system sounds like what I need.

I assume the HFS-4 has the failsafe built in?

I was thinking of replacing the 2 jets where they are now (pre Throttle body) plus the 3rd one out back pre-turbo - What would you suggest for placement?

Re: HFS-4 Q&A, application for your engine...
 

Yes, the H4 has an inbuilt turbine based flow sensor failsafe as standard.