Lotus technical director Nick Chester says his team is aiming to close the gap on Williams after emerging as the fourth fastest outfit in the Chinese Grand Prix.
The team finally scored its first points of the season in Shanghai thanks to Romain Grosjean finishing in seventh position.
The Mercedes-powered E23 has shown promising speed, however, with Grosjean having started all three races so far in the top ten, and only problems having prevented him from scoring sooner.
"Fourth fastest was certainly true in China," said Chester. "Red Bull still show flashes of being pretty quick and given their development rate, they'll be hard to keep behind.
"We haven't got a big gap to Sauber and Toro Rosso.
"It's a very tight grid and we have to keep bringing performance upgrades to maintain this position and then start to improve competitiveness.
"Obviously it is very tight in the midfield and it will be a development race between ourselves, Red bull, Toro Rosso and Sauber.
"We are all aiming at closing the gap to Williams."
Chester admitted scoring points for the first time in 2015 was a boost for the team after the missed chances of the first two races.
"It was very important. We knew that we had a competitive car and it was frustrating in Sepang and in Melbourne not to get any points on the board.
"It's great for the team to have scored these points in Shanghai."