Do I need a new hat?

Enderle bird 12.25x4 opening on a ssi f3 with 11.5x4.5. Shelf in the back when looking along the airflow. Max rotor rpm So far is 11,400. I need another tenth which I can probably get with a pulley swap. But more than anything, I want to get the bolts out of the airflow path ( Baaad experience).

So, I thought I was going to go with a spacer mostly to solve the bolt problem, and maybe pick up a couple hundredths while I was at it, but can't find anything the right size.

There's a veney hat for sale in my budget but was told it would be too restrictive. A used BAU at a good price would be great, but would the Veney be better than my current Bird??

 

A big & ugly and an SSI F3 with an 11.5 opening is a very good combo. The back of the injector opening can be blended back a little for a good match.

 

If you are going to run a restraint between the hat and blower, find one with a slightly smaller opening than the blower. Then lay it on the blower and scribe a line on the under side at the rear blower opening. Then turn the hat up-side-down and lay the restraint on the hat with the bolt holes aligned. blend the hat and restraint together to the scribed line from the blower opening. If you are getting a big & ugly this works good.