Toro Rosso's Pierre Gasly believes the lack of grunt of his Honda engine down Silverstone's straights has taken away the gains achieved by the STR13 handling qualities.
Gasly's car was the single Toro Rosso to run in qualifying on Saturday after a suspension failure and massive crash sidelined Brendon Hartley for the session.
The Frenchman underlined his car's performance but lamented its lack of straight-line speed, pinning its deficit on its Honda engine.
"The car was mega, but with the long straights at the moment it’s crazy how much time we lose," he said.
"We knew that on a track like this, with Turn 1 and 9 being flat-out we’ll struggle. We’re talking about nine tenths compared to Force India and Sauber, so yeah, very difficult to fight.
"But in the corners, looking at the GPS, we are faster and it looks pretty good, but just on the straights at the moment we are really slow.
"Objectively we have no pace, not coming from the car, but from the engine."
The 22-year-old qualified 14th on Saturday, a result that was actually beyond his expectations.
"We were actually surprised to go into Q2 because we lost so much time in the straights since the beginning of the weekend," he admitted.
"You cannot recover nine tenths in the corners. In the end it was a good day, but the race will be difficult.
"In normal conditions at the moment we need to find much more straightline speed. In terms of the car I don’t think we can extract much more potential."
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