Find your horsepower in the row, then read across. Total head is the lift from the pumping water level to the discharge, plus the pressure you want at the tank (2.31 ft for every PSI), plus friction in the drop pipe.
Total head in feet · curves end at 121.5 GPM
| HP |
0 GPM (Shut-off) |
25 GPM |
62.5 GPM |
87.5 GPM |
112.5 GPM |
| 3 HP |
143 ft |
130 ft |
106 ft |
88 ft |
66 ft |
| 5 HP |
263 ft |
251 ft |
206 ft |
163 ft |
114 ft |
| 7 1/2 HP |
414 ft |
379 ft |
296 ft |
229 ft |
156 ft |
Read from the published curve in the Pumps by Baker catalog (Sept 2025, rev 3/26), p. 90, digitized and rounded down, at the flows nearest 20%, 50% and 75% of the curve’s 121.8 GPM end. 0 GPM is the printed shut-off. For the 3 HP and 5 HP curves, the published curve and A.Y. McDonald’s printed output tables disagree by about 14 and 11 ft on average; the head figures are read from the curve, and the output tables below are the printed figures. The last column is the last flow every curve reaches; the curve ends are named in the table title.
Output in GPM at 30 PSI (switch cut-in), by depth to water
| HP |
60 ft |
100 ft |
120 ft |
140 ft |
160 ft |
180 ft |
200 ft |
| 3 HP |
100 |
— |
— |
— |
— |
— |
— |
| 5 HP |
— |
76 |
65 |
51 |
35 |
20 |
— |
| 7 1/2 HP |
— |
— |
— |
— |
86 |
80 |
72.5 |
Output in GPM at 50 PSI (switch cut-out), by depth to water
| HP |
60 ft |
100 ft |
120 ft |
140 ft |
160 ft |
180 ft |
200 ft |
| 3 HP |
— |
— |
— |
— |
— |
— |
— |
| 5 HP |
75 |
50 |
32 |
15 |
— |
— |
— |
| 7 1/2 HP |
— |
— |
80 |
77 |
70 |
63 |
55 |
Output tables as printed in the Pumps by Baker catalog (Sept 2025, rev 3/26), p. 89, at the 30 and 50 PSI rows. Riser-pipe friction is not included (manufacturer note): add it for long or small drop pipe. — marks a point A.Y. McDonald does not print for that horsepower.
Best operating range: the published curve shades the most efficient operating range for each model; the catalog prints no figures for it. The curve is in the image gallery.
