Here is my version of a 1x cam signal for the Holley sequential port EFI. I started with a stub out from BOP, and made up the machined pieces to build up the extra length necessary to allow for a Hall effect sensor mounted vertically.
Inside there is a shutter type of wheel with a notch to give a “falling edge” trigger to the sensor. The pieces will be hard anodized after fit check. Note the cam drive gear is upside down in the photos.
Motor is a 461 with Old Faithful HR cam (modified to 114 LSA), and KRE 305 CFM heads.
Hall effect sensor
Shutter wheel with cap removed
Cap inverted with sensor protruding through
Steel washers fabbed up to keep the distrubtor clamp from tearing up the soft aluminum
Mock up on the block