If you are using a "constant on" venting system, then DON'T use a bigger intake than exhaust.
This is what I do for a COMPLETELY smell free setup (other than in the room itself)
I had a 400W 8" exhaust fan combined with a carbon filter. I had a 6" passive intake....no fan on the intake. Just a 6" flap.
By pulling air out of the room faster than it comes in, the room has a "negative pressure".
If you push more air in than out, you end up pushing stink out of tiny cracks, thus negating the point of the carbon filter. The stink finds its way out without being "scrubbed" or filtered.
Do what you wish but I would NEVER have a powered intake that is bigger than my exhaust.
I used an ozone machine on a timer in the "outer" rooms during lights off time. My plants stunk much less in dark so a masking device worked fine during lights off.
No one had a clue I was growing, and I had several parties at my house. No one ever smelled my plants. Of course I locked the basement door when people were over so they couldn't smell the "ozone" if lights were off or hear the fans and ballasts when lights were on.
