790 cfm fan pulling through Y from 2 6inch 425cfm filter?

[Centrum]

Redesigning some things, have some 6inch 424cfm fans blowing hot air through lights pulling from outside room and blowing outside room.
Have an 8 and 10 inch fan left over.


Has anyone ever pulled through two 6 inch 425cfm max rated filters using a Y duct and a stronger than rated fan ?

My thoughts are 425 and 425 = 850 and using a 790 cfm fan would = it out ?
Or am i totally off base ?

 

[Oysters]

Two 6" filters connected to an 8" fan using an 8x6x6 wye duct would work just fine.

 

[Centrum]

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