Rockabillyrat
SlIgHtLy StUpId.
There is alot of wrong information out there about injectors. Like 40hp marine injectors. Or one vendor out there claiming marine injectors dont have a throttling pintle... both of those statements are completely false.
The injectors do three important things for fuel delivery into the combustion chamber. Spray pattern, flow rate curve and duration. The pintle design determines the spray pattern. The stock and marine injectors throttle fuel on initial opening identically. The only difference is once the marine injector reaches full needle lift the pintle design allows for more flow. Thus changing the flow rate and spray pattern.
Pop pressure is used to control duration. Higher pressure means the same fuel volume in a shorter amount of time. Lower pressure makes duration longer. Thats why pop pressure has increased on the 6.x platform over the years because the fuel volume was increased. And marine pumps flow the most, which explains the highest stock pop pressure. The best way to make power is the most fuel in the shortest amount of time. So increasing pop pressure is a good way to optimize performance. And on a modified pump or tuned DS4 its required to keep duration times short.
What the sweet spot for duration should be is something no one knows other that the engineers that designed it. But I'm determined to figure that out. That and pintle design to get the desired flow rate curve. The Idi is a two part combustion process and I believe fueling needs to be correct to optimize that process. Ive been itching to post about what I've been up to the past 6 months.... stay tuned.
The injectors do three important things for fuel delivery into the combustion chamber. Spray pattern, flow rate curve and duration. The pintle design determines the spray pattern. The stock and marine injectors throttle fuel on initial opening identically. The only difference is once the marine injector reaches full needle lift the pintle design allows for more flow. Thus changing the flow rate and spray pattern.
Pop pressure is used to control duration. Higher pressure means the same fuel volume in a shorter amount of time. Lower pressure makes duration longer. Thats why pop pressure has increased on the 6.x platform over the years because the fuel volume was increased. And marine pumps flow the most, which explains the highest stock pop pressure. The best way to make power is the most fuel in the shortest amount of time. So increasing pop pressure is a good way to optimize performance. And on a modified pump or tuned DS4 its required to keep duration times short.
What the sweet spot for duration should be is something no one knows other that the engineers that designed it. But I'm determined to figure that out. That and pintle design to get the desired flow rate curve. The Idi is a two part combustion process and I believe fueling needs to be correct to optimize that process. Ive been itching to post about what I've been up to the past 6 months.... stay tuned.
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