Mercedes has been a step above its competition during Formula 1's V6 turbo era, but the manufacturer is still aiming to improve for next season.
Mercedes engine boss Andy Cowell told Autosport they are close to producing a Formula 1 engine that can deliver a power output of 1000bhp.
"We're close," Cowell said. "I'm sure that'll happen at some point."
Mercedes has four straight double world championships, and its engine exceeded 900bhp in 2016. It also broke the 50 percent thermal efficiency barrier for the first time.
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Thermal efficiency has become increasingly important for teams and manufacturers in recent years, and Cowell said they will continue to monitor the thermal efficiency before next season.
"We need to see how the power unit development goes through the winter and our prove-out goes through the winter, and it's a balance with the car as well," Cowell said.
"There are engines running on the dyno - that's one thing.
"When you go to total car lap time, that's the bit where there's work being done to improve the technology on the car to enhance both aerodynamic and power unit performance."
Lewis Hamilton dominated for Mercedes in 2017, and he earned his fourth championship. If the team and manufacturer improve for next year, he could possibly win his fifth title next season.