re-red cube
- Thread starter Rob
- Start date
The general concern here is pressure drop across the sensor. Here's an older thread with some discussion on the point. I'll believe that before we started distributing the red cube (FT-60), EI actually had a more strongly-worded recommendation to use the FT-90 in gravity fed systems. The advantage of that sensor is that has a lower pressure drop than FT-60, but the downside is that it's lower rating for measurement is 2 gph. We pointed out that at the flow rates that most of our customers were seeing, the pressure drop is a few 10ths of a PSI at most, not inhibiting fuel flow, and they agreed, removing the restrictive wording. You'll note inthe attached documentation that you'll still want to run the calculations to be sure you're OK. It's truly when you have a larger GA motor plus a gravity fed fuel delivery that the pressure drop can be a factor, and that was likely the real basis for the former partitioning of the two models. That said, you can use either the FT-60 or FT-90 with our system. We only sell the FT-60 though.