diff --git a/src/p_mobj.c b/src/p_mobj.c
index 843123d57eb2c8a7df1bb160ec32d9a5110f0aa4..2cf94e835f3c7f00a82e454826b2e382c9ca1e96 100644
--- a/src/p_mobj.c
+++ b/src/p_mobj.c
@@ -2377,10 +2377,7 @@ static boolean P_ZMovement(mobj_t *mo)
 		if ((mo->eflags & MFE_VERTICALFLIP) ? tmceilingslope : tmfloorslope) {
 			mo->standingslope = (mo->eflags & MFE_VERTICALFLIP) ? tmceilingslope : tmfloorslope;
 
-			// Reverse quantizing might could use its own function later
-			mo->standingslope->zangle = ANGLE_MAX-mo->standingslope->zangle;
-			P_QuantizeMomentumToSlope(&mom, mo->standingslope);
-			mo->standingslope->zangle = ANGLE_MAX-mo->standingslope->zangle;
+			P_ReverseQuantizeMomentumToSlope(&mom, mo->standingslope);
 		}
 #endif
 
diff --git a/src/p_slopes.c b/src/p_slopes.c
index 8df94e757a1364adb88a6ebba24fc50d8f3c8260..d939fee98b9cb36f015da6cb187131acc6407eb6 100644
--- a/src/p_slopes.c
+++ b/src/p_slopes.c
@@ -767,6 +767,17 @@ void P_QuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope)
 	FV3_Rotate(momentum, &axis, slope->zangle >> ANGLETOFINESHIFT);
 }
 
+//
+// P_ReverseQuantizeMomentumToSlope
+//
+// When given a vector, rotates and aligns it to a flat surface (from being relative to a given slope)
+void P_ReverseQuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope)
+{
+	slope->zangle = InvAngle(slope->zangle);
+	P_QuantizeMomentumToSlope(momentum, slope);
+	slope->zangle = InvAngle(slope->zangle);
+}
+
 //
 // P_SlopeLaunch
 //
@@ -810,12 +821,7 @@ void P_HandleSlopeLanding(mobj_t *thing, pslope_t *slope)
 	mom.y = thing->momy;
 	mom.z = thing->momz*2;
 
-	//CONS_Printf("Landing on slope\n");
-
-	// Reverse quantizing might could use its own function later
-	slope->zangle = ANGLE_MAX-slope->zangle;
-	P_QuantizeMomentumToSlope(&mom, slope);
-	slope->zangle = ANGLE_MAX-slope->zangle;
+	P_ReverseQuantizeMomentumToSlope(&mom, slope);
 
 	if (P_MobjFlip(thing)*mom.z < 0) { // falling, land on slope
 		thing->momx = mom.x;
diff --git a/src/p_slopes.h b/src/p_slopes.h
index dd9b6f2d2def8a28c89b3daba5d878e3be133f06..de38f1d9ed279be0059a8c0a283a337d8e4e7bb8 100644
--- a/src/p_slopes.h
+++ b/src/p_slopes.h
@@ -35,6 +35,7 @@ fixed_t P_GetZAt(pslope_t *slope, fixed_t x, fixed_t y);
 
 // Lots of physics-based bullshit
 void P_QuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope);
+void P_ReverseQuantizeMomentumToSlope(vector3_t *momentum, pslope_t *slope);
 void P_SlopeLaunch(mobj_t *mo);
 void P_HandleSlopeLanding(mobj_t *thing, pslope_t *slope);
 void P_ButteredSlope(mobj_t *mo);
diff --git a/src/p_user.c b/src/p_user.c
index 499966798ae8cb43b170d84df0ad1f08dba70c4a..7bf2b1f66c0578edc129b38daeef4da66a191adf 100644
--- a/src/p_user.c
+++ b/src/p_user.c
@@ -1851,12 +1851,8 @@ static void P_CheckBouncySectors(player_t *player)
 						momentum.y = player->mo->momy;
 						momentum.z = player->mo->momz*2;
 
-						if (slope) {
-							// Reverse quantizing might could use its own function later
-							slope->zangle = ANGLE_MAX-slope->zangle;
-							P_QuantizeMomentumToSlope(&momentum, slope);
-							slope->zangle = ANGLE_MAX-slope->zangle;
-						}
+						if (slope)
+							P_ReverseQuantizeMomentumToSlope(&momentum, slope);
 
 						newmom = momentum.z = -FixedMul(momentum.z,linedist)/2;
 #else
@@ -2856,7 +2852,7 @@ static void P_DoTeeter(player_t *player)
 	fixed_t topheight, bottomheight; // for 3d floor usage
 	const fixed_t tiptop = FixedMul(MAXSTEPMOVE, player->mo->scale); // Distance you have to be above the ground in order to teeter.
 
-#define maxzdelta 3<<(FRACBITS-2) // 3/4 on the fixed scale
+#define maxzdelta 1<<(FRACBITS-1) // 1/2 on the fixed scale
 	if (player->mo->standingslope && player->mo->standingslope->zdelta >= maxzdelta) // Always teeter if the slope is too steep.
 		teeter = true;
 #undef maxzdelta