The Japanese engine manufacturer spent three years teamed up with the Woking outfit, but a messy divorce at the end of the 2017 season.
Honda then teamed up with the Toro Rosso team for this season, and brought about their best result since their return, a P4 finish in Bahrain thanks to Pierre Gasly.
However, according to Franz Tost, the Japanese manufacturer did not know too much.
“We had very good cooperation and we have a very good business relationship. If there is something which we detect on our side, we sit together, we discuss it, and then we try to find a solution,” Tost said.
“When we had the first meeting together with Honda, I was shocked, because they didn’t know things which are related to the chassis or power unit.
“If you are coming together with a new partner, first you have to sit together to discuss to find out where we need to be concentrating.
“But it went very fast and very well because they were totally open and so were we from our side.”
The off-track communication was the biggest change between Honda’s relationship with McLaren, and their current time with Toro Rosso.
“The Toro Rosso philosophy is generally that we are transparent because our only target is to be successful,” he said.
“There are absolutely no politics within the team. We have a really good relationship.”
Tost admitted that 2018 would be a difficult season for the team during its transition, but praised Honda for surpassing their expectations.
“I said last year quite clearly that it will not be an easy season, because of technical topics, which we have to sort out,” the Toro Rosso boss admitted.
“But in the end, I must say that the power unit from Honda showed a much better performance than the chassis of Toro Rosso.”