I would guess that better than 50% of the vehicles running in Altered or Comp Coupe run a Dry Sump tank inside of the cockpit and most of those run AT LEAST A FIVE GALLON TANK MINIMUM. The reason for that size of a tank is to compensate for oil lost in the motor, pan, hoses, filters, pump and tank during a wide open run.
In my car I built a nine gallon tank and run six gallons of oil which allows a large area above a anti-aeration screen for the returning oil (two AN-16 lines) and I also run two vent lines to a puke tank in the trunk.
I see no reason that a properly installed dry sump tank should need to be isolated by a firewall in a race car unless you require the same for water tanks which can explode from a head gasket failure (think steam), or pressurised intercooler boxes (think explosive power).
Lets not open another can of worms unless research shows proof of previous injuries-not caused by improperly built or installed systems.
By the way, I run a six stage Barnes rotor gear pump with four scavenge lines off of the pan and one from a manifold I built that lays in the lifter galley.
I run two hot water style heater elements in the tank (which has been talked about in another thread.... maybe blanket type external heaters might be a better way to go).
I also use Moroso inline screens on all five scavenge lines, a System one screen canister filter, and a two quart Wix Nascar screw on filter.
I lost a intake roller lifter roller at the W.F.'s, which resulted in two broken Carrillo rods, toasted crank, damaged and possibly ruined Dart Block, but believe it or not the bearings show very little distress, the filters look good, and the only damage to the Barnes pump was scuffing of the rotors in two scavenge segments.
Bob Drury