Do you think passive exhaust will be sufficient new build

Hello all,

Currently roughing in my hvac intake and outtake. My setup is 540 cubic feet and I am using a 6" fan with 473 CFM. I am running 2 400 watt HPS and 1 315 CMH.Do you guys think a passive exhaust will cut it, my budget is stretched very thin and I have plants vegging in my garage that need me to finish this build haha.

That seems really big for just a single 6" exhaust fan. You may be stretching it there...especially with the heat those guys are going to kick off.

How tight is your budget? Could you go to an 8"?

This guy is 740 CFM and would certainly do the job: (I'm using the 6" version and love it!)

Very tight haha I already have the fan from years ago

Maybe if I just ran 2 400w?