Honda Power Unit Hardware & Software

[63l8qrrfy6]

Well actually it's not that hard, numerical solutions for torsional vibration in reciprocating engines and drivelines have been around since 1920s and have since evolved to the extent that they can capture any relevant behaviour with near perfect accuracy.

Also tire loads are not really relevant since the torsional stiffness of the tire is very low compared to that of the driveline.

Well, actually it's not that near perfect as you purport it to be. There's nothing like simulating dynamic loads than on track testing. Also no point in bringing up McLarens operations as they were unfit to provide Honda a team environment let alone a decent gearbox in time. Imagine if Honda was still inside the Mcl33. It would have been a proper disaster and McLaren would have hidden behind the engine and Honda would be wrongfully the laughing stock.
So enough of this misinformation about Honda not being able to do this or that, seriously.

As I've explained but you seem to have missed the point is that the low tire stiffness decouples the rest of the driveline from whatever happens at the contact patch. The tire is a very effective torsional AV mount and as such for all practical purposes whatever happens at the contact patch has no effect on the torsional vibration of the driveline.

I missed the bits in the press about Honda being able to run dynos with a gearbox - if that is the case they should have all the tools required to diagnose and fix driveline oscillations.

[63l8qrrfy6]

The formula one clutch is nowadays part of the gearbox and no longer fitted to the end of the crankshaft.

Uhm evidence seems to suggest the exact opposite. Merc pics clearly show the clutch basket on the crank while the shape of the Honda cover seems to also hide a clutch mounted on the crank.

F1 NA engines had the clutch within the gearbox to raise the natural frequency of the crank - this is no longer required in current engines since the excitation frequency is lower.

Looking for information about gearbox control I found this Honda R&D article related to gearbox control from 2009:
http://www.f1-forecast.com/pdf/F1-Files ... P2_26e.pdf
If you look at page 204 it shows the post shift oscillation producing when upshifting. It looks that this problem is not new, as it already appeared during the V8 era and a mitigation system was proposed. So, why this problem is so difficult to be solved now? Maybe the team that worked in the gearbox in the past is not part of Honda anymore and this problem needs to be addressed in the gearbox control design?

The problem can be solved in multiple ways (relaxing the clutch, increasing shift time, spark, etc) - however most of them involve losing performance.

Remember last year when Merc got very greedy with aggressive shift times and had to take gearbox penalties early.

+1 for the paper - can't believe I did not have it!

[subcritical71]

Snagged this from youtube (https://youtu.be/HJ3EIbhwx2w?t=83), Its a Merc in the Honda forum I know! ;

[ringo]

I think it may be possible to mount the turbo lower if the clutch is moved into the gearbox and the turbine lowered closer to engine's output shaft.
If the turbine shaft isn't at the lowest point limited by the rules, i can imagine that the clutch is the limiting factor in the turbines height.

[Maritimer]

I think it may be possible to mount the turbo lower if the clutch is moved into the gearbox and the turbine lowered closer to engine's output shaft.
If the turbine shaft isn't at the lowest point limited by the rules, i can imagine that the clutch is the limiting factor in the turbines height.

The motor is probably the limiting factor for how low the turbo can be placed.

[godlameroso]

I wonder what kind of release bearing they use for the clutch. I'm guessing it's likely a hydraulic, what's not obvious is whether it's a push or pull type.

[godlameroso]

I think it may be possible to mount the turbo lower if the clutch is moved into the gearbox and the turbine lowered closer to engine's output shaft.
If the turbine shaft isn't at the lowest point limited by the rules, i can imagine that the clutch is the limiting factor in the turbines height.

The motor is probably the limiting factor for how low the turbo can be placed.

The MGU-H is the main limiting factor + min weight and COG are specified in the rules. MGU-H is min 4kg + the rest of the turbo is probably another ~10kg for the turbine wastegates/actuators etc, another ~6kg for the compressor, so that's 20kg affecting COG you have to account for. IE the lighter you make them the more you limit how low you can place them.

Maybe there's some strategic benefit to making certain parts heavier if it means being able to lower them a bit, or vise versa. Maybe making something lighter and having to raise it a bit can lead to a net gain by opening space somewhere else.

[saviour stivala]

I wonder what kind of release bearing they use for the clutch. I'm guessing it's likely a hydraulic, what's not obvious is whether it's a push or pull type.

http://imagesvc.timeincapp.com/v3/found ... quality=85

https://racecarsdirect.com/content/User ... 10.jpg?v=1

for a long time now pull type pressure plate spring have been in use in FI. When they were using clutch mounted in gearbox they eliminated the pull loading on crankshaft end-float thrust.

[saviour stivala]

The pressure plate pull type spring on Sachs 95mm diameter clutch of 2008 had a spring loading on the friction plates of 1.6 tons.

[godlameroso]

The pressure plate pull type spring on Sachs 95mm diameter clutch of 2008 had a spring loading on the friction plates of 1.6 tons.

That's on par with a lot of twin plate clutches. But sounds about right for 800ish hp.

[63l8qrrfy6]

Don't forget that the clutch is only really used in anger during launches - it is massively under specified compared to clutches for more conventional gearboxes.

[anthonyfa18]

on the RA618H where is the MGU-k location ???? i don't see in any photos ?? can in be inside the block and use oil to cool it ???

[PlatinumZealot]

Does anyone have an idea what Hondas new combustion process is?

No one knows except Wazari. The last information we had was from 2018 and that was a pre-chamber ignition. Team Wazari had a new take on that and that is fully borne out in 2018 Spec 3.

[DC2]

Does anyone have an idea what Hondas new combustion process is?

No one knows except Wazari. The last information we had was from 2018 and that was a pre-chamber ignition. Team Wazari had a new take on that and that is fully borne out in 2018 Spec 3.

I wasn't around for a while. Can someone tell me what happened with Wazari? I really enjoyed Wazari's insight the last few years.

[Sieper]

Chased of the forum by a few who thought he wasn't who he said he was end felt entitled to keep on pushing that opinion. It was moderated way too late unfortunately.