Ferrari may now have overtaken Mercedes as the maker of the best engine in Formula 1.
Red Bull competes with F1's third best engine, the Renault.
'They have power to spare'
"They (Ferrari) have a super engine. Our chassis is probably the best of the top three cars, but we couldn't get past them. They have power to spare," Christian Horner told Brazil's Globo in Austria.
Horner's colleague Dr Helmut Marko agrees.
"You do not have to look too hard to see the impressive power they have," he said.
'Ferrari are ahead of us'
And even reigning world champion Lewis Hamilton thinks Ferrari has finally overtaken Mercedes in the power stakes.
"They're ahead of us in that sense, there's no question," said the Mercedes driver.
Even Sauber boss Frederic Vasseur admitted that the Swiss team's surprising boost in form this year is in large part due to the 2018 Ferrari engine.
"Having the same version of the Ferrari engine is making all the difference for us.
We are improving our chassis step by step, but it is undeniable that we have the help of this year's engine," he said.