diff --git a/code/ZAS/_gas_mixture_xgm.dm b/code/ZAS/_gas_mixture_xgm.dm
index 06f7e0d70a..b193fb1692 100644
--- a/code/ZAS/_gas_mixture_xgm.dm
+++ b/code/ZAS/_gas_mixture_xgm.dm
@@ -128,15 +128,27 @@
 		. += ratio * specific_entropy_gas(g)
 	. /= total_moles
 
-//Returns the ideal gas specific entropy of a specific gas in the mix. This is the entropy due to that gas per mole of /that/ gas in the mixture, not the entropy due to that gas per mole of gas mixture.
+/*
+	Returns the ideal gas specific entropy of a specific gas in the mix. This is the entropy due to that gas per mole of /that/ gas in the mixture, not the entropy due to that gas per mole of gas mixture.
+	
+	For the purposes of SS13, the specific entropy is just a number that tells you how hard it is to move gas. You can replace this with whatever you want.
+	Just remember that returning a SMALL number == adding gas to this gas mix is HARD, taking gas away is EASY, and that returning a LARGE number means the opposite (so a vacuum would approach infinity).
+
+	So returning a constant/(partial pressure) would probably do what most players expect. Although the version I have implemented below is a bit more nuanced than simply 1/P in that it scales in a way 
+	which is bit more realistic (natural log), and returns a fairly accurate entropy around room temperatures and pressures.
+*/
 /datum/gas_mixture/proc/specific_entropy_gas(var/gasid)
 	if (!(gasid in gas) || gas[gasid] == 0)
 		return SPECIFIC_ENTROPY_VACUUM	//that gas isn't here
 	
 	var/molar_mass = gas_data.molar_mass[gasid]
 	var/specific_heat = gas_data.specific_heat[gasid]
-	//group_multiplier gets divided out in volume/gas[gasid]
-	return R_IDEAL_GAS_EQUATION * ( log( (IDEAL_GAS_ENTROPY_CONSTANT*volume/gas[gasid]) * sqrt((molar_mass*specific_heat*temperature)**3) + 1 ) +  5/2 )
+	
+	//group_multiplier gets divided out in volume/gas[gasid] - also, V/(m*T) = R/(partial pressure)
+	//This equation is not accurate at all, but should work well enough for a game. 
+	//Based on the form of Sackur-Tetrode + some curve fitting to specific entropy tables for N2 gas + some adjustments to make it work down to 0 K 
+	//(the real S-T equation does not work at low temperatures, you need quantum mechanics to do it, but screw that) and with the specific power atmos machinery calculations.
+	return R_IDEAL_GAS_EQUATION * ( log( (IDEAL_GAS_ENTROPY_CONSTANT*volume/(gas[gasid] * temperature)) * (molar_mass*specific_heat*temperature)**(2/3) + 1 ) +  15 )
 
 //Updates the total_moles count and trims any empty gases.
 /datum/gas_mixture/proc/update_values()
diff --git a/code/setup.dm b/code/setup.dm
index 361cfaa66c..267fab61a9 100644
--- a/code/setup.dm
+++ b/code/setup.dm
@@ -837,8 +837,8 @@ var/list/RESTRICTED_CAMERA_NETWORKS = list( //Those networks can only be accesse
 
 //These balance how easy or hard it is to create huge pressure gradients with pumps and filters. Lower values means it takes longer to create large pressures differences.
 //Has no effect on pumping gasses from high pressure to low, only from low to high. Must be between 0 and 1.
-#define ATMOS_PUMP_EFFICIENCY	0.6
-#define ATMOS_FILTER_EFFICIENCY	0.45
+#define ATMOS_PUMP_EFFICIENCY	1.0
+#define ATMOS_FILTER_EFFICIENCY	1.0
 
 //will not bother pumping or filtering if the gas source as fewer than this amount of moles, to help with performance.
 #define MINUMUM_MOLES_TO_PUMP	0.01