by Thomas Vaught » Sun May 22, 2005 2:37 pm
I like the fixed multiple hole plate.
This is the way a SF 1200 is made.
Make the holes so that you have a 300 cfm hole, a 200 cfm hole,
a 100 cfm hole, and a 50 cfm hole.
Your ranges available will now be:
50,100,150,200,250,300,350,400, 450, 500, 550, 600, and 650.
There are several spots where you can cross-check your flow calibration by using different holes.
For example:
The 300 cfm range (using a single hole or the 100 and 200 holes).
the 350 range with the 300 and 50 cfm holes vs the 200, 100, and 50 cfm holes, etc.
Most heads do not flow more than 350 cfm so this is a good calibration check point.
JMO
Use rubber stoppers to close off the holes you are not using for flowing.
Tom V.