Honda's recent progress has partly been the result of the Japanese manufacturer's collaboration with an outside consultant believed to be llmor.
According to Motorsport.com, Mario Illien's engineering company was brought in earlier this year to help Honda solve its persistent reliability and performance issues.
Honda would not reveal the identity of the manufacturer's consultants but did admit that outsourced work had been conducted.
"Although we do not deny the possibility of working with outsources [consultants], we do not disclose the details," said a Honda spokesman.
"We are now working on the development of the 2018 power-unit but nothing specific can be mentioned at this time, other than the fact that we are working very hard to get further improvement to become more competitive in coming season."
Honda's Yusuke Hasegawa also revealed that the manufacturer had changed its approach to engine development and analysis by relying less on mono-cylinder dyno testing and more on data from its V6 power unit, a process which has also brought productive gains.
But Honda's recent progress, which put both McLarens in the points in Hungary before the summer break, comes at a time when the Woking-based outfit must decide whether to extend its partnership with Honda or seek an engine supplier agreement with Renault, its only viable alternative.
According to reports, McLaren sounded out the French manufacturer but Renault is rumored to be hesitant to extend its efforts to a fourth outfit in addition to Red Bull Racing, Toro Rosso and its own works team.
To complicate matters further at Woking is Fernando Alonso, lurking in the wings as he ponders an F1 future with or without McLaren, depending on his team's potential for success in 2018.