How much gap between the spinner backplate and the cowl should i have?
This is on a pulse xt with a os 46 ax.
Thanks

If you maintain 1/16" while an electric starter (worst case scenario) is in contact you will be fine. You can go 1/8" if you want. Beyond that it becomes obvious that you may have changed spinner styles or something else has changed the gap. You can always think of a suitable excuse.

1/16 to 1/8 always looks good.