is this too much of a tight fit for a rack?

Is there anything that even gets that hot? If not, like Jeff said, I wouldn't worry.

If it was rack mounted tube gear, then it's good to leave some spaces... Or if one of the rack items generates a lot of heat it's good to leave some space so it's not heating up adjacent gear.
 
Depends how hot your space gets. If your getting in the 80-90 deg range on hot days in the room then yes it's to close. If you can keep the room 75 deg ish and under then you should be fine.
 
I think it's ok.

OT: What is the 8-channel pre you have below the FF800?
 
I'd check each piece of gears manual. Sometimes the manual will say if it needs space or not. Our apogees specify 1RU above and below open for ventilation, but it depends on the individual gear...
 
Yeah, audient, love the thing :)

And i didnt hook up the bbe for a while, but for some remix stuff its still pretty cool at times if guitars arent working with only eq, way better then the plug.
But even so.... didnt use it in forever......
 
If you've got the digital card in the Audient, I'd be REALLY weary about that setup. Mine gets pretty hot after only a few hours of use, and I have a full space, with vents, between it and my Saffire Pro 40. I can't imagine how hot it'd get with it being right up against your FF800 and POD...