Honda convinced of competitive engine

Jenson Button and Rubens Barrichello both complained that they lacked top speed on the straights last season - which could have been a reference to the power of the Honda RA806E engine.

With teams having to use the same engine next season, any deficiencies suffered from in 2006 will likely be carried forward into the new year.

However, Honda's senior technical director Shuhei Nakamoto and engine project leader Kazuo Sakurahara are adamant that the lack of straightline speed was simply a result of the RA106 car suffering from high drag.

Although Nakamoto does not goes as far as claiming the Honda engine is by far the best in the field, he is convinced it is as good as any of its rivals.

"If you asked if our RA806E had exceptional performance compared to others, the answer would be no," he said.

"But we were not behind the others. During pre-season testing we felt we were behind Renault, but it was only about the total package including the chassis, and not only about the engine. We admit we were certainly behind in terms of chassis development."

He added: "The horsepower figures were reasonably high. The engine did not rev as highly as some others, as it has a relatively small bore and a long stroke. While other engines needed 20,000rpm, we must have produced the same amount of horsepower at about 19,500rpm."

Honda claim that they only got on top of their main engine issues, including reliability and improving the torque delivery, in the second half of the 2006 season.

And the fact that the team homologated their 2007 engine after Suzuka, with a power unit that included parts originally intended to only appear in an all-new 2007 engine, has left them bullish for next season.

Sakurahara said: "Honda started to show its true potential in 2006 after the German race. On the engine development side, the first part of the season involved repeated trial and error using the data arriving from the circuits.

"During the latter half of the season, we started to yield results as we understood how we could use the V8 engine during the race through the analysis of data accumulated during the first half of the season.

"It was a turbulent year going through the development of an all-new V8 engine and having to cope with the challenge of homologation for 2007, but we were encouraged by the fact that we were able to end the season on an upward curve with the results that were seen at both Suzuka and Interlagos."

Sakurahara claims that most of the team's engine failures over the course of the season were the result of poor quality control rather than out-and-out design failures.

"In the first season we encountered a total of seven engine failures in the course of the 18 Grands Prix weekends, all of which were reciprocation-related problems," he said.

"Many of them were caused by uneven quality of the parts affected by vibration in the crankshaft area. The quality of the parts had never been a problem with V10 engines. As a result we had to improve quality control of the parts for (the) V8 engine."