For those who want economy, reduce the IDC startup point, you have discussed it before for someone with a petrol with huge injectors. Allow fuel to be replaced at low load states. Since diesels have gotten more complicated, the ability to tune them like a gasser (i.e. ECU load based instead of pressure based from the IP) has become the norm, the tuning for a kit would need to be based on fuel flow, rather than pressure. The DR will allow this (low load states, low spray, with enough left over up top) to happen.
PPS systems get around the DR with multiple stages. But, a second stage adds $100 + on top of a kit ($20 nozzle, $10 holder, $55 solenoid, $25 hobbs switch, $5 Y-fitting, $1-3 hose). Add this price to the cost of a progressive kit ($360 for a DO kit), and the HFS-2 is right in line.
If you want to sell to the power hungry, it should be as simple as enlarging your intank fitting to a 3/8”, and running 10-12mm hose to the pump. I did this because of a weak pump, but as
Howerton
http://howertonengineering.com/2010/...-hfs-6-system/
Alkycontrol, You, Labonte, and others have said, bigger hose pre-pump allows for less stress on the pump at all rates. If they want to go real big, mass produce (maybe not mass produce, but allow the choice) for the two nozzle/valve kit like the above hyperlink shows.
Have you considered bigger jets? Like in the 10-14 gph/600-1000cc/min range? The real price of nozzles has gotten high in the last few years, with DO at $20 plus $8 holder, and Coolingmist at $37 for nozzle, and $14 for the two fittings. 6.7L diesel at 50-75+psi can drink A LOT of water. Buying different nozzles to figure out what is needed can be expensive. At a certain point the big boys go gear-driven
http://www.scheiddiesel.com/display_part/2782.php
but that is beyond your scope anyway.
Consider longevity. Some diesel drivers in the US will have the kit installed, and it will be on 80%+ percent of the time. Some will only use it for pulling or drag racing. I know of a member on another forum that has logged 200K miles in 2 years, killed a pump, melted two controllers, then built his own controller after modifying a snow controller with a ridiculous heatsink that still didn’t work. Your pump is designed to run all of the time, which will be nice, but what about the controller and the valve? Can it take 50% duty cycle for 4-6 hours constant?And finally, since this has become a novel rather than a post, don’t try to hype it up. Not that you have in the past, but… The numbers are in your favor. Data will sell the kit. Flow curves, cc/min comparisons at different load states, and pricing will sell the kit. Make sure they understand that they don’t need a $1000 Snow MPG-MAX with two nozzles because one nozzle with the AM kit can flow at 5-50 times the range of a PPS system. Start with the HFS-2, because you don't have a failsafe figured out.
As a side note, and something you should feel free to dismiss, is to consider NPT and English based fittings and hose. I know here in Japan, everything is metric, and I have to bring over English fittings if I want to change things, but I know that when looking for 1/4” to M5 fittings in the US to install on the used HSV I found, I had to spend quite a bit of time looking, and had to go to some sketchy place in an industrial park that purchased surplus fittings. I know that it will play with logistics for you, but for those who already have a US based PPS system, the main problem is that nothing we have can convert over. The pump is already NPT, and the 1/8 NPT fitting that you use for the nozzle holder is getting there. I have some 1/8 NPT to 6mm OD quick connects, but that is because I am here in Japan and can walk down the street.
Telling Americans to sell the kit they have and buy yours might be the smartest thing for them if all they have is an as purchased kit, but if they have picked up a lot of parts over the years, it will be difficult to get the money back for some of it. I have 10 nozzles from m0.5 up to m15 that I can convert to an aquamist kit if I want to, but some may not see it that way.
I’m convincing myself to buy a TDI in 10 months and do a PPS to PWM-V test. Will the HFS-2v2 be able to do most of what the HFS-4 can do?