Venturi size

Looking for some help, I'm making a few venturis using the nylon bushings mentioned in a post here. One will be for the ENYA 19, the other for the ST .23. I have the ST one turned down to fit the throat of the intake, and drilled for the spray bar. I am using the OS remote needle and spray bar assy. off the newer style engines.

What size should the venturi bore be when using this spray bar?

How about the .19? same size?

Does the spray bar act as the bore reduction, or do I gain something from machining a taper in the bore above the spray bar?

Thanks guys

For the .19 try a .228
For the .23 try a .234

The needle working as a restrictor alone will work, but if you can get the taper to come down to the needle or close to it, that would be better.

Thanks Leonard.