Jordan King has said there is a noticeable performance gain from Manor since the previous in-season test in Barcelona in May.
GP2 driver King, who drove in the second day of the two-day Silverstone test earlier this week said that the team has improved massively since last season, with the biggest step coming in the last two months.
"I think actually the most performance gain I’ve seen is from the Barcelona test through to this test just gone,” King said. "There’s a big gap in between the end of last year and this year: it’s a new car, it’s all a bit different, we’ve got the new engine which is a big improvement."
"But after driving the car in Barcelona when it’s still the start of the season and they’re getting to understand the car to where they are now, it’s a big improvement actually. I was quite impressed and gave them some more feedback on the direction they need to go."
King first tested for Manor last season, when the team was firmly a backmarker, but King now believes the team is knocking on the door of the midfield.
"They’re actually now really pushing the midfield of the grid and scored the first point the other weekend. And it’s clear to see why after jumping in the car and seeing the progress they’ve made during the season."
Since last season the team has switched for 2014-spec Ferrari engines to the latest version of Mercedes' class-leading V6 Hybrid power unit, but King says that with Formula One's engine suppliers getting ever closer, the team must work hard on their car if they are to continue scoring points.
"That obviously helps, they’ve got the Mercedes engine, but it’s clear now that actually Ferrari and Renault are there or thereabouts," he said. "Red Bull have won races and are consistently scoring podiums and also Ferrari are right up there as well."
"So I think actually the engine playing field is a lot more even so it’s obviously great for the sport but it’s also made it harder for Manor because they actually now need to work solely on their car."