Vacuum Motor Requirements

[ivoryk3ys]

Good Afternoon! I ordered the plans just the other day and have been trying to learn.

I am very much an amateur and a visually impaired one at that but I want to mess around and test things and maybe see if I can port some using a good camera to help me. I have a 72 Duster with a 408 Stroker I designed for it that my brother is the driver of for me.

I want to start out small being it's a hobby that and it will be in a shed in my carport (possibly at my parents in my fathers garage but I want to start with it here).

I was thinking of starting with just two motors. I was looking at the Lighthouse 119563-120. I assume that would allow me to test up to at least 350cfm at 10"? I am wondering what pressure that might allow me to test to a maximum of say 350? The vac just shows 145cfm at 2" I don't know if that means that would be 45cfm at 10"?

I do understand that at least 28" is ideal due to more realistic and useful velocities and how that affects the flow path and I am sure other reasons. You have to start somewhere though and I am sure some good testing and porting have been done using the SF110.


If there is a formula or somewhere I can look at the vac specs and figure this out that would be great.

Thanks a lot

Kevin

[Brucepts]

On motor selection you want to look at the total static pressure your flowbench will see and compare that to the flowchart for the motor at that pressure, this will give you a good idea of what your motors will actually flow. It's not exact but it's a good indication

So if you are testing at 10" and using a differential pressure of 16" you would have: 10+16=26" total pressure so go to the chart and look at the cfm @26" If testing @28" you would have: 28+16=44" so you would look at the cfm @44" if you do not see the exact number you can kinda get and idea of the cfm between the numbers you see on the chart.

There is really not a set formula to find this out sorry to say . . .

[Tony]

Welcome to the Forum Kevin.

If you look up the data on the 119563, and from the line on the top chart (that has the solid squares) its rather difficult to see even with good eye sight.

Testing at ten inches (10 +16=26 inches required) would give you about 120 CFM per motor.
Testing at twenty eight inches (28+16=44 inches required) would be about 85 CFM per motor.

[ivoryk3ys]

Thank you for the help and the welcome I appreciate it!

Yes Tony you are right that is a small chart but I zoomed it and see what your pointing out and I will make sure to take account of the pressure differential.

[Tony]

When you build your bench, make provision for fitting extra motors, then just blank off the extra holes. Its almost zero extra work, but one day you may be very glad you did this.

[ivoryk3ys]

Yes I definitely want to make sure it's open for that. I played with the numbers some it looks like 5 of those motors are kinda the magic number to be able to flow up to 350cfm area at 28"(44").