Honda Power Unit Hardware & Software

[Wazari]

Honda stated on many occasions that even though it was an MGU-H or K that failed, rather than attempt to change those parts it's a lot more efficient timewise to just change the entire package ICE included.

Having said that, why not use the same ICE units over again in the pool unless they had hardware issues with the ICE?

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

[stevesingo]

I don’t think MGU-K is throttled. It is either on 120kw or off. Otherwise there is no 120kw reduction in power and the flashing rear light would not be triggered. It is just 120kw assist when throttle is floored, until the Ecu shuts it down or ES is depleted.

It is not set in the regulations that it must be 0 or 120kW, what is stated is the maximum is 120kW. The level of deployment through the MGU-K will be determined by the engine mode used, along with the amount of MGU-H recovery, and energy flow paths from MGU-H to ES and MGU-K. If there is limited capacity available in the ES then it makes sense to use MGU-K power at the beginning of the acceleration zone as the aero drag is much lower and you get better bag for your buck in terms of acceleration.

Remember that the MGU-K is bi-directional, providing positive torque under acceleration and negative torque under braking and perhaps during non-maximal driver torque demand (gen set). If then you take the regen under braking, there must be provision to modulate the negative torque applied by MGU-K to the engine during braking, a 0 or 120kW strategy would play havoc with brake balance.

About ICE power: It could be possible that crankshaft power is comparable and that Mercedes gain is made in the amount energy that is generated in the exhaust gasses and recovered by MGU-H. We already know the engines are running extremly lean and take much more air than needed. Maybe it is just to expand/heat the air during combustion and recover this with MGU-H and use it for more deployment.

You can only recover a limited amount of energy from the MGU-K under braking, less than you can deploy under acceleration. This is because the cars are at WOT longer per lap than they are under braking and the limit is 120kW both ways. The remainder can be made up by MGU-H recovery, the problem is, the more thermally efficient your ICE is, the less is available for MGU-H. Running super lean has two benefits, one is that the expansion of the excess air helps pushing the piston and provides more gasses for MGU-H. Therein lies the main problem for Honda is that if the rumours that they can't get the TJI type ignition functioning as they would want, then the opportunity to run as lean as they would like is less.

[GhostF1]

Well this year has certainly been a "unique" one. I wonder if maybe Wazari could share any insights he may have on the general mood at Honda and their confidence in their 2018 PU. The first time running a second iteration of a current engine layout, surely the mood for 2018 is a good one?

[wuzak]

The first time running a second iteration of a current engine layout, surely the mood for 2018 is a good one?

Surely the 2016 unit was a development of the 2015 architecture?

There was an improvement from 2015 to 2016, especially in reliability terms.

[MrPotatoHead]

Honda stated on many occasions that even though it was an MGU-H or K that failed, rather than attempt to change those parts it's a lot more efficient timewise to just change the entire package ICE included.

Having said that, why not use the same ICE units over again in the pool unless they had hardware issues with the ICE?

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Yeah I had a feeling this was the case.
Makes some sense from packaging and rigidity, but makes no sense from a maintenance / repair stand point.
Explains why they just swap the whole unit.

And if anyone has had a turbo fail you'll know they have a high chance of causing damage to the ICE, especially if it's on the compressor side.

At the end of the day the engine is designed to be modular and is easier to replace it all.
If only they were not penalized for such problems.

[FW17]

If the MGU H is sharing the block, high chance the cooling circuit is same as engine, either water cooled with engine coolant or oil cooled with engine oil.

[dren]

If the MGU H is sharing the block, high chance the cooling circuit is same as engine, either water cooled with engine coolant or oil cooled with engine oil.

Sounds like it is just for the MGUH shaft.

[ziggy]

Honda stated on many occasions that even though it was an MGU-H or K that failed, rather than attempt to change those parts it's a lot more efficient timewise to just change the entire package ICE included.

Having said that, why not use the same ICE units over again in the pool unless they had hardware issues with the ICE?

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Yeah I had a feeling this was the case.
Makes some sense from packaging and rigidity, but makes no sense from a maintenance / repair stand point.
Explains why they just swap the whole unit.

And if anyone has had a turbo fail you'll know they have a high chance of causing damage to the ICE, especially if it's on the compressor side.

At the end of the day the engine is designed to be modular and is easier to replace it all.
If only they were not penalized for such problems.

This is one of the things I don't understand. The whole MGUH + turbo + compressor should be made as a separate unit in a separate housing and should be "floating" on springs or some kind of dampers. This way it would be isolated from the whole car stress. Offcourse packaging wise this would be a nightmare, but should be doable. Also separate parts should be changeable, so a failure of only 1 component doesen't result in a whole unit change.

Surely there were some reasons for this way, maybe cooling or packaging?

[MrPotatoHead]

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Yeah I had a feeling this was the case.
Makes some sense from packaging and rigidity, but makes no sense from a maintenance / repair stand point.
Explains why they just swap the whole unit.

And if anyone has had a turbo fail you'll know they have a high chance of causing damage to the ICE, especially if it's on the compressor side.

At the end of the day the engine is designed to be modular and is easier to replace it all.
If only they were not penalized for such problems.

This is one of the things I don't understand. The whole MGUH + turbo + compressor should be made as a separate unit in a separate housing and should be "floating" on springs or some kind of dampers. This way it would be isolated from the whole car stress. Offcourse packaging wise this would be a nightmare, but should be doable. Also separate parts should be changeable, so a failure of only 1 component doesen't result in a whole unit change.

Surely there were some reasons for this way, maybe cooling or packaging?

I agree. Hindsight is a wonderful thing though.
I'm sure it was driven by packaging / center of gravity.
Every mm counts. Microns in some cases.
We're talking about a world where every supplier of every component has to bag and weigh each part after they are ready to send to the teams to ensure the weight is within a gram of what it is supposed to be.
F1 is something else.

[MrPotatoHead]

Honda stated on many occasions that even though it was an MGU-H or K that failed, rather than attempt to change those parts it's a lot more efficient timewise to just change the entire package ICE included.

Having said that, why not use the same ICE units over again in the pool unless they had hardware issues with the ICE?

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Also - if the Spec 3 vs Spec 4 units are really that much different it makes more sense why the "Spec 4" unit was never run in the car this year.

I think it should be given a different name though, Spec 3 vs Spec 4 sounds like just another iteration of the same engine. If the Engine Block is different then it should be given a completely different engine designation.

[etusch]

Our spec 4 will have different Mgu-h architecture and mgu-h produced by Honda's themselves.
Can we assume that the engine FRANZ TOST talked about is spec 4 or Honda showed them current PU which is using by McLaren?

[Wazari]

Well this year has certainly been a "unique" one. I wonder if maybe Wazari could share any insights he may have on the general mood at Honda and their confidence in their 2018 PU. The first time running a second iteration of a current engine layout, surely the mood for 2018 is a good one?

The mood at Honda is very upbeat according to my nephew. I am no longer at Sakura. I hear there is a sense of relief and great optimism for the upcoming season. After the season is over and the marriage is finally done, I will post about what I feel are the mistakes made by both parties.

[GhostF1]

The first time running a second iteration of a current engine layout, surely the mood for 2018 is a good one?

Surely the 2016 unit was a development of the 2015 architecture?

There was an improvement from 2015 to 2016, especially in reliability terms.

I struggle to say it was identical, the whole compressor/mgu-h/mgu-k design was completely redesigned and the position was raised substantially higher. They'd have zero data for track behaviour and general in-car performance with this setup, so although there were similarities and the ICE was a similar concept, everything else was not.

Next year I believe they are keeping the same general concept. Hasegawa seems confident they are on the right path.

[Wazari]

Honda stated on many occasions that even though it was an MGU-H or K that failed, rather than attempt to change those parts it's a lot more efficient timewise to just change the entire package ICE included.

Having said that, why not use the same ICE units over again in the pool unless they had hardware issues with the ICE?

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Also - if the Spec 3 vs Spec 4 units are really that much different it makes more sense why the "Spec 4" unit was never run in the car this year.

I think it should be given a different name though, Spec 3 vs Spec 4 sounds like just another iteration of the same engine. If the Engine Block is different then it should be given a completely different engine designation.

They are quite different and I will go into greater detail after the season is over. I will say this, the current Spec 3.XXX series PU is a mish-mash of HRD, McLaren (MAT), outside consultants and internal consultants. IMO this will never work. Too many cooks in the kitchen. The "Spec 4" PU is more of the "Honda way" which all the "experts" think is doomed for failure. The Spec 4 PU has a different block, internals, MGU-H, etc. The Spec 4 heads will mate to the current PU.

[fellowhoodlums]

The casing the houses the shaft is part of the block and time to swap the MGU-H would be extremely time consuming. Don't ask me why it was designed this way. Spec 4 is not.

Also - if the Spec 3 vs Spec 4 units are really that much different it makes more sense why the "Spec 4" unit was never run in the car this year.

I think it should be given a different name though, Spec 3 vs Spec 4 sounds like just another iteration of the same engine. If the Engine Block is different then it should be given a completely different engine designation.

They are quite different and I will go into greater detail after the season is over. I will say this, the current Spec 3.XXX series PU is a mish-mash of HRD, McLaren (MAT), outside consultants and internal consultants. IMO this will never work. Too many cooks in the kitchen. The "Spec 4" PU is more of the "Honda way" which all the "experts" think is doomed for failure. The Spec 4 PU has a different block, internals, MGU-H, etc. The Spec 4 heads will mate to the current PU.

But the spec4 is still on the rig, it may have more potential but it's been nearly there since mid 2017 and originally designed almost a year ago. Lots of wrong turnings from Honda about design.