[Richard L]

DO two-stage kit @$460, only $35.00 below the HFS-2. Our kit compares favoritably in terms of dynamic range.

Based on the HFS-2, we just need to actively maintaining the line pressure by PWM'ing the pump, keeping the heat dissipation low. We might justy call it HFS-2D. I can also see the advantage of track fuel fuel instead of boost. Most modern diesel ramps into full boost at the slighest touch of throttle. So tracking boost is a non-starter.

NPT is imperial (inched), used main in imperial hose sizes such as 1/4", 5/32, etc. BSP is used widely for all metric hoses. So if Japan is Metric, BSP is common there?

I am not keen on NPT fitting because I cannot use o-ring seals at the mating surfaces. Using plumbers tape (PTFE) can cause all sort of clogging problem is a small piece of torn tape is allow to travel towards the valve or the jets. We use NPT on the jet adaptor for the ease of adjusting the depth or thin wall charge pipes.

The HFS-2/3 is due for a version upgrade, we can introduce these options if we decided to go into the diesel market. Alternatively we might just offer a brand new Diesel system with EGT probe. We now have a 1.2mm nozzle flowing ~650cc/min @150psi

With the modern diesel, we can easily alter the boost or reduce power by trimming fuel upon failsafe activation. One thing I do want to know badly, what is the most attractive feature a diesel drive want. It is quite easy to figure out what the turbo/gasoline drivers want.