there is a really great interview with hasegawa on autosport prem. In short, everything worked well when honda tested on mono cylinder, they thought it was actually pretty easy, but the reality hit as they where to transfer from mono to the actual pu, suddenly nothing worked,
ive really really appreciated this thread! by far the most interesting to follow pre season, so thanks to all!
i really cant give more since its prem. but at the same time the non members here need see this so it can be in your future pu analysis
"As a matter of fact we were thinking [it was] too easy, [but] it was too difficult to achieve the new technology,"
"What we achieved in [the] mono-cylinder is at a very good level, but when we transfer exactly the same specification to the V6 engine it doesn't work.
"If you put [too] much fuel into the number-three cylinder you lose something from elsewhere. Theoretically, the exhaust pressure wave has more influence in a four-cylinder engine, but in a three-cylinder engine it doesn't - technically speaking. We didn't think there would be a big effect from mono-cylinder to V6, but as a matter of fact it affects very much.
"We have to avoid that area (rev range) - we have huge vibrations," Hasegawa explains. "The only thing I can tell is that on the dyno we didn't have such a big issue. When we have a gearbox, driveshaft and tyre, it has some resonance. Please understand I'm not blaming the chassis, we have to realise the situation on the dyno as well."
Hasegawa admits Honda has missed its power target, saying the new engine has "almost the same power" as last year's engine, which of course means it has gone backwards from its 2016 position of being 80bhp away from Mercedes, which in turn is believed to have added another 70bhp to its own performance over the winter.
Barcelona will be the "latest" point at which Honda introduces an updated specification.
the journalist points
The new combustion engine proved unstable and lacking driveability. Short-shifting to improve traction caused detonation at low revs; engine behaviour within the optimum rev range was so wild that the drivers had to over-rev the engine to tame it. But that meant less power. What's more, huge vibrations through the drivetrain caused the car to shake itself to bits, leading to persistent electrical failures.