Minimum Injector PW question

[underpsi68]

I am currently running SD 83lb injectors with a base fuel pressure of 52psi. My minimum injector PW is 1.8ms at idle right now. I am interested in purchasing a set of 160lb Moran injectors. They have a minimum injector opening of 1.5ms. If I lower the base fuel pressure to 3 bar will these injectors idle at or above 1.5ms with the same idle rpm and A/F? I am not sure if there is a formula on how to figure this out.

This is running with an SM4

Thanks for any help

[Ian]

A 3bar 83 lb injector at 52psi base pressure will have a flow of 83*((52/44.1)**0.5) = 90lb.

If you assume (big assumption though) the injectors are basically linear at those low pulse times then you would expect a 160lb injector to want to run at about 1ms compared to a 90lb injector at 1.8ms. So a minimum of 1.5ms will rule that injector out.

What about ID2000 injectors? From their info they have very linear control down to low (sub 1 ms) pulse times. I don't know if the spray pattern suits your application but reports seem to be favourable.

[underpsi68]

In my thinking if I double the injector size the pw won't get cut in half at low pw. Wouldn't the injector dead time have to be factored into the mix? The injector doesn't spray as much when it is starting to open or close plus you have the reaction time of the injector.

The newest version of the moran injectors have a min pw of 1.2ms right now. That will help out some.

I did look at the id injectors. Imo the morans have a superior spray pattern, are rebuildable, they can be used with any fuel including meth,mtbe and q16, they can also be resized if needed and moran offers too notch support. The morans are also about $300 cheaper. The morans are about $135 an injector compared to $175 for the ids.

Ah what to do lol