| 1 | A | B | C |
| --- | --- | --- | --- |
| 2 | ALCO HH series - Specifications |  |  |
| 3 | Overall length | 45 ft 2.75 in | 13.79 m |
| 4 | Between bolster centers: | 21 ft 3 in | 6.48 m |
| 5 | Truck wheelbase: | 8 ft 0 in | 2.44 m |
| 6 | Width over grabirons: | 9 ft 10 in | 3.00 m |
| 7 | Height above rails: | 14 ft 3 in | 4.34 m |
| 8 | Wheel diameter: | 40 in | 1.02 m |
| 9 | Fuel capacity: | - | - |
| 10 | Engine (HH600): | McIntosh & Seymour 531 | McIntosh & Seymour 531 |
| 11 | Power (HH600): | 600 hp | 450 kW |
| 12 | Engine (HH900): | McIntosh & Seymour 531T (turbocharged) | McIntosh & Seymour 531T (turbocharged) |
| 13 | Power (HH900): | 900 hp | 670 kW |
| 14 | Engine (HH660): | McIntosh & Seymour 538 | McIntosh & Seymour 538 |
| 15 | Power (HH660): | 660 hp | 500 kW |
| 16 | Engine (HH1000): | McIntosh & Seymour 538T (turbocharged) | McIntosh & Seymour 538T (turbocharged) |
| 17 | Power (HH1000): | 1000 hp | 750 kW |
| 18 | Main generator: | - | - |
| 19 | Traction motors: | - | - |
| 20 | Standard gearing: | - | - |
| 21 | Weight: | - | - |

Question: Which type of engine improved upon the HH900 engine and what is the total horsepower?
Answer: The HH1000 replaced the HH900, replacing the 531 engine with the new McIntosh and Seymour 538T engine, turbocharged to produce 1000 hp (750 kW), a 100 hp increase on the previous model.