The team submitted eight technical changes to the FIA for the Silverstone weekend. These are led by a reworked floor with a raised edge, a tweaked diffuser to reduce how much the wake from the rear tyres distorts the airflow and wider engine cover bodywork.
An extra winglet has been added to the rear suspension wishbone and a revised rear and beam wing introduced to reduce drag and improve straight-line performance.
But after Tsunoda clocked 16th in FP1 before running to 18th, the Japanese driver says the updates have not provided an immediate boost.
Asked by Autosport to assess his first laps aboard the revised AT04, Tsunoda said: “So far, we can't see the results that we are improving massively.
He added that a couple of improvements were noticeable from the cockpit but, in some areas where the team had expected to take a step forward, the gains had not arrived.
Tsunoda said: “So far, it’s not looking good. The result is no good so far.
“We feel definitely a couple of gains in some places but some places we didn’t improve that we expected. So, we have to look through it deeply.”
Source: Autosport