Honda Power Unit Hardware & Software

[PlatinumZealot]

All turbo’s are limited to 120000 rpm by Fia rule. A smaller turbo needs a higher average rpm, so less headroom to increase in thin air.

Honda is on par with Mercedes now, but the Redbull chassis works better on these high altitude tracks. Allot of Topspeed is coming from the faster corner speed in turn 12.

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

[gruntguru]

With all else being equal, a BIGGER turbo will cope better with high altitude.

[GhostF1]

With all else being equal, a BIGGER turbo will cope better with high altitude.

This... I'm surprised there are media outlets spouting the opposite. It's a pretty fundamental fact.

[GhostF1]

The power is now on par with Mercedes in qualifying? Or is it because of altitude?

Mercedes engineers told that they believe that Honda is strong in high altitudes which shows that they have advantages on electrical side.

It's definitely not this. It actually implies the opposite.. that their ICE/Turbo concept is giving them the advantage.

[Sieper]

All turbo’s are limited to 120000 rpm by Fia rule. A smaller turbo needs a higher average rpm, so less headroom to increase in thin air.

Honda is on par with Mercedes now, but the Redbull chassis works better on these high altitude tracks. Allot of Topspeed is coming from the faster corner speed in turn 12.

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

They ran less wing and Max had DRS both times he was behind Lewis.

Ho pin Tung says a smaller turbo is an advantage at altitude.

[1158]

Max did not have DRS for the second pass on HAM. It was on the restart.

[GhostF1]

All turbo’s are limited to 120000 rpm by Fia rule. A smaller turbo needs a higher average rpm, so less headroom to increase in thin air.

Honda is on par with Mercedes now, but the Redbull chassis works better on these high altitude tracks. Allot of Topspeed is coming from the faster corner speed in turn 12.

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

They ran less wing and Max had DRS both times he was behind Lewis.

Ho pin Tung says a smaller turbo is an advantage at altitude.

No offence to Ho Pin Ting (who is a racing driver, not an engineer nor would he have any access to Honda's PU dimensions, let alone dimensions to compare to Mercedes) but a smaller compressor does not have altitude advantages in the way he is suggesting. It goes against basic principles...

It sounds like he's reaching from 2016 where Honda had the turbo inside the V and consequently, limited compressor size... that is not even remotely close to the situation now. Especially when Honda have matched Merc at normal altitude tracks recently.

[Bence]

Just to give an additional source (motorsport):

Mercedes F1 technical director James Allison explained that as there are only two races that are significantly affected by this, trading a compromised package in Mexico and Brazil is better for the balance of the full campaign.

“You try to design the turbo and compressor unit to be good over the whole season,” said Allison.

“You can size your compressor to cope with Mexico and with here, but then you're carrying around hardware that's bigger than it needs to be for the rest of the year. It's always a compromise doing that. And I think probably looking at the last few seasons when we're at altitude, we always tend to be just a little bit less on form.

“That's probably an indication that the position we have picked our compromise is slightly different to the others. That's our best guess.”

[GhostF1]

Just to give an additional source (motorsport):

Mercedes F1 technical director James Allison explained that as there are only two races that are significantly affected by this, trading a compromised package in Mexico and Brazil is better for the balance of the full campaign.

“You try to design the turbo and compressor unit to be good over the whole season,” said Allison.

“You can size your compressor to cope with Mexico and with here, but then you're carrying around hardware that's bigger than it needs to be for the rest of the year. It's always a compromise doing that. And I think probably looking at the last few seasons when we're at altitude, we always tend to be just a little bit less on form.

“That's probably an indication that the position we have picked our compromise is slightly different to the others. That's our best guess.”

Yes and that makes sense. So this Merc engineer is saying a larger turbine would be more suited to high altitude (which actually makes sense unlike what other media outlets are reporting). What's interesting about James' comments is it implies Merc believe Honda probably have a larger sized turbo or not just larger, their design is less compromised. Whatever it is, it doesn't look like it affects their performance at sea level tracks either.

[gruntguru]

There will be an optimum turbo size for the high altitude tracks and another for sea level. No doubt all the teams have sized their turbo somewhere in between - probably closer to the sea level case since there are more circuits close to that altitude.

[stevesingo]

Mark Hughs

The Honda, like the Renault, uses a turbo smaller than that of the Mercedes, one which can more easily compensate for the thinner air by spinning faster to further compress the thinner air. At its lower homologated burst point speed, the Mercedes turbo is not quite compensating fully for that 25 per cent reduction in air density.

Is the burst speed homologated? I've seen nothing in the regs to that effect. Max speed is defined in the regs and likely measured real time by the SCU, but there is nothing stating the PU manufacturer has to prove anything other than, when in use, the turbo rpm does not exceed 120k rpm.

Sounds journo BS to me.

[PlatinumZealot]

All turbo’s are limited to 120000 rpm by Fia rule. A smaller turbo needs a higher average rpm, so less headroom to increase in thin air.

Honda is on par with Mercedes now, but the Redbull chassis works better on these high altitude tracks. Allot of Topspeed is coming from the faster corner speed in turn 12.

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

They ran less wing and Max had DRS both times he was behind Lewis.

Ho pin Tung says a smaller turbo is an advantage at altitude.

Ho ping tung is a driver. James allison is a chief engineer. James said Merc need a bigger compressor to work better at altitude. And it does make sense. A bigger compressor makes a bigger pressure ratio for the same Rpm.

[Capharol]

All turbo’s are limited to 120000 rpm by Fia rule. A smaller turbo needs a higher average rpm, so less headroom to increase in thin air.

Honda is on par with Mercedes now, but the Redbull chassis works better on these high altitude tracks. Allot of Topspeed is coming from the faster corner speed in turn 12.

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

They ran less wing and Max had DRS both times he was behind Lewis.

Ho pin Tung says a smaller turbo is an advantage at altitude.

Sieper Ho Pin Tung isn't all knowing ... so don't believe every word he says and some parts he can't know because he ain't driving F1 which has completly different intakes as WEC or any other categorie he drives.

yes his knowledge is good for general analisys, but indept analisys is not his strong point

[PlatinumZealot]

I believe Mercedes still have cooling problems they just did a good job of keeping it hush. They likely down rated the engineand there is some evidence pointing towards that. One, Lewis was on the radio begging for more power and so was Valterri. They got what they wanted and one car retired from overheated oil.

[subcritical71]

The honda compressor could be bigger also.. Or their variable inlet guide vanes could also be better designed for altitude. Whatver it is the power difference combined with their chassis sure is noticeable on the climb up the hill.

They ran less wing and Max had DRS both times he was behind Lewis.

Ho pin Tung says a smaller turbo is an advantage at altitude.

Sieper Ho Pin Tung isn't all knowing ... so don't believe every word he says and some parts he can't know because he ain't driving F1 which has completly different intakes as WEC or any other categorie he drives.

yes his knowledge is good for general analisys, but indept analisys is not his strong point

Something to consider when discussing compressor sizing, and this is reading between the lines on my side. Generally a larger diameter compressor would give you more flow. But there are some limits other than speed/size to consider. If the Merc have a larger diameter compressor than Honda they very well may not be able to reach the max allowable RPM due to speed of sound limitations at the compressor tips (exceeding mach 1 in a compressor means an entirely different design). If the Honda have a smaller compressor they may be able to reach a higher RPM (closer to max allowed RPM) at high altitude density tracks and compensate for the density difference where the Merc or anyone with a larger diameter compressor cannot.