I just received 2 ST46 engines back from rebuild by Frank Bowman.  He did an awesome job and over time I will send all my STs to him.

The question I have is that I now need Venturis and NVA for them.  I have looked around and know that there are two types available for the ST, a true/sprinkler and the restrictor/center type.  Also, there are aluminum and delrin venturis.  Is there an advantage of one over the other?

I also want to ask if it would be wise to have several different intake diameters for tuning purposes when I eventually place these in planes?

Thomas