Honda Power Unit Hardware & Software

[NL_Fer]

It is race strategy. If you start the race with 15kg less weight at front row. With full power they sprint away, built a 10s gap, than turn down the engine, safe fuel and the engine and cruise home.

Saving the engine gives the team more ability to stress it in Q3. Take front row and we start the cycle again.

[henry]

I think it very likely that they drive the K directly from the H.

Godlameroso suggested 50 or 60 kw for the H.
In race mode.
Car A MGU-H makes 60 kw. 2 MJ of ES can deploy the MGU-K for 33.3 secs and when the limit is reached you can still motor at ICE + 60 kw

Car B MGU-H makes 50 kw. 2 MJ of ES can deploy the MGU-K for 28.6 secs and thereafter ICE + 50.

So car A will be quicker because it can run at higher power at high speed at the end of straights.

However there is another way to extract the advantage.

At most circuits they can only recover about 1 mJ under braking. So they have to burn fuel to charge further. They have 2 methods.

At part throttle they run against the K charging the ES at 120 kw. Depending how good the H is they may supplement this with excess power from the H.

At full throttle they divert H power from K to the ES

To extract the advantage in the example above you charge the ES to 2 mJ. However you could also charge the ES to less than 2 mJ, burn less fuel and so start with a lighter car. So now a car with a superior H, car A, can still match the deployment duration of car B but corner faster and accelerate more quickly. This may well be more effective than longer deployment.

Potentially there is some positive feedback when all you are trying to do is match lap times. Now car A can reduce the ES charge still further use less fuel, run lighter etc.

I don’t imagine there is a 10 kw difference between the engines but this mechanism would amplify any superiority in H output and lead to a significant difference in starting fuel loads.

[OO7]

Hi Wazari

The Mercedes can't be 10% more efficient than the Ferrari and the Renault isn't a more efficient unit than the Ferrari.

Oh yes.. it is not about Thermal efficiency alone.. but fuel mileage.. very different metric.. How you get better fuel mileage is all about race management. Normally cars at the front will need less fuel during the race. When you beat your rival to the punch - he has to sit back in the hot air... he needs more cooling.. he has to turn down his boost.. he has to run richer. But at the same time he is losing time in the corners so he needs more power on the straights to make up for it, he might have to overtake a few cars.While you out front can cruise after the first stint and benefit as the car gets lighter and even more fuel efficient. You get the picture.

I agree there are other components to this, however 10% in my opinion is too large a difference considering it was averaged over the last 15 races. Other teams also optimise for fuel mileage with Renault and Honda often sacrificing D/F for straight line performance. That Mercedes is able to match and beat Ferrari in a straight line consistently while apparently using 10% less fuel would means their PU is 10% more efficient (the differences in deployment strategy wouldn't account for such a consistently large variation, plus we have witnessed that deployment between the to PUs is similar). Mercedes hit the 50% efficiency mark this year and we heard Renault's Rob White state a few years ago that the PUs were well over 40% efficient.

[OO7]

It is race strategy. If you start the race with 15kg less weight at front row. With full power they sprint away, built a 10s gap, than turn down the engine, safe fuel and the engine and cruise home.

Saving the engine gives the team more ability to stress it in Q3. Take front row and we start the cycle again.

How about when Ferrari starts on the front row?

[drunkf1fan]

Speaking of fuel efficiency, I averaged the starting fuel loads for some teams for the last 15 races and came up with these figures:

McLaren 103.7 kilos, Ferrari 101.8 kilos, RBR 100.5 kilos, Mercedes 91.2 kilos, That's a huge advantage.

Where exactly are those numbers coming from?

[drunkf1fan]

It can't? Are those figures about fuel efficiency or more about deployment strategy and harvesting? Those are the fuel loads averaged over the last 15 races including Brazil. I don't have the figures for the first few races.

You guys know way more than me on all matters engine/PU related, but I would have thought fuel efficiency (instantaneous) and harvesting (ERS-H) were related. The more energy the MGU-H can harvest, the more it can send to the MGU-K.

K deployment per lap is limited by regs.

K deployment is not limited by regs. There are two proper regulations on energy and one minor one. The minor is simply that mgu-k can't be used during race start till after cars reach 100km/h, presumable as the somewhat unintentional but definitely that traction control/torque smoothing from the mgu-k control(feel wheel spin, harvest heavily, no wheel spin, up the torque fill till traction slip detected) makes race starts too predictable.

The two major regulations on power are, the battery can only send 4MJ per lap to the MGU-K and the MGU-K can only send 2MJ per lap to the battery. The battery can send unlimited power to the mgu-h, the mgu-k can send unlimited power to the mgu-h and the mgu-h can send unlimited power to the battery and the mgu-k.

The only major limitation, as the mgu-h harvests more than the mgu-k and when the mgu-h is harvesting the most it's most efficient(with no power conversion loss) to send it direct from mgu-h to mgu-k right at the point it's needed, is how much you can harvest.

[PlatinumZealot]

Hi Wazari

The Mercedes can't be 10% more efficient than the Ferrari and the Renault isn't a more efficient unit than the Ferrari.

Oh yes.. it is not about Thermal efficiency alone.. but fuel mileage.. very different metric.. How you get better fuel mileage is all about race management. Normally cars at the front will need less fuel during the race. When you beat your rival to the punch - he has to sit back in the hot air... he needs more cooling.. he has to turn down his boost.. he has to run richer. But at the same time he is losing time in the corners so he needs more power on the straights to make up for it, he might have to overtake a few cars.While you out front can cruise after the first stint and benefit as the car gets lighter and even more fuel efficient. You get the picture.

I agree there are other components to this, however 10% in my opinion is too large a difference considering it was averaged over the last 15 races. Other teams also optimise for fuel mileage with Renault and Honda often sacrificing D/F for straight line performance. That Mercedes is able to match and beat Ferrari in a straight line consistently while apparently using 10% less fuel would means their PU is 10% more efficient (the differences in deployment strategy wouldn't account for such a consistently large variation, plus we have witnessed that deployment between the to PUs is similar). Mercedes hit the 50% efficiency mark this year and we heard Renault's Rob White state a few years ago that the PUs were well over 40% efficient.

OK by your argument, you say that the efficiency difference between Honda and Mercedes that Wazari's data is suggesting is too large? OK. By Wazari's data.. Honda is using 13.7% more fuel than Mercedes in the race. (note that the cars are NOT doing the same work in real life... the Honda is working harder to finish the races.. but anyway lets go along with it). So if Mercedes is 50% thermally efficient Honda will be (91.2/103.7*50)= 44% thermally efficient.

That is just about where Mercedes started in 2014. Accounting for the fact that Honda's race fuel mileage will be awful compared to Mercedes in real life, Wazari's fuel mileage numbers do not seem alarming?

McLaren 103.7 kilos, Ferrari 101.8 kilos, RBR 100.5 kilos, Mercedes 91.2 kilos, That's a huge advantage.

[diffuser]

Speaking of fuel efficiency, I averaged the starting fuel loads for some teams for the last 15 races and came up with these figures:

McLaren 103.7 kilos, Ferrari 101.8 kilos, RBR 100.5 kilos, Mercedes 91.2 kilos, That's a huge advantage.

Where exactly are those numbers coming from?

I 2nd that emotion.

Must be some inside numbers.....

[FW17]

Speaking of fuel efficiency, I averaged the starting fuel loads for some teams for the last 15 races and came up with these figures:

McLaren 103.7 kilos, Ferrari 101.8 kilos, RBR 100.5 kilos, Mercedes 91.2 kilos, That's a huge advantage.

Where exactly are those numbers coming from?

I 2nd that emotion.

Must be some inside numbers.....

Fuel weights were on TV in 2014, then they stopped displaying it. Maybe the teams are given access to it.

[OO7]

OK by your argument, you say that the efficiency difference between Honda and Mercedes that Wazari's data is suggesting is too large? OK. By Wazari's data.. Honda is using 13.7% more fuel than Mercedes in the race. (note that the cars are NOT doing the same work in real life... the Honda is working harder to finish the races.. but anyway lets go along with it). So if Mercedes is 50% thermally efficient Honda will be (91.2/103.7*50)= 44% thermally efficient.

That is just about where Mercedes started in 2014. Accounting for the fact that Honda's race fuel mileage will be awful compared to Mercedes in real life, Wazari's fuel mileage numbers do not seem alarming?

Thanks for the calculation PZ.
The efficiency of the Mercedes relative to the Honda looks good, but relative to the Ferrari you get (91.2/101.8*50)= 44.8%. That doesn't seem right at all.

[Singabule]

That figure including sauber one? So the Ferrari unit maybe the strongest in outright power, but need to turn down severely at some point of race. While merc turn it down most of races? So the Ferrari and Mercedes rivalry this season is bullshit, merc is sandbagging RBR is the most efficient chasis out there, so the number seems right

[OO7]

That figure including sauber one? So the Ferrari unit maybe the strongest in outright power, but need to turn down severely at some point of race. While merc turn it down most of races? So the Ferrari and Mercedes rivalry this season is bullshit, merc is sandbagging RBR is the most efficient chasis out there, so the number seems right

Even accounting for Sauber, the Ferrari figure doesn't look right, being barely ahead of Honda.

[f1316]

I don’t know how the majority on here (other than those with inside knowledge) can have much basis for what *looks right*.

We have reasonable data (Q3 performance, straight line speeds) to assume that the Ferrari is relatively close to the Mercedes in terms of peak power but little to go on that tells us anything about efficiency and, perhaps more importantly, strategy.

Because this is also about tactics for how you choose to go racing and how you want to achieve longevity from your PU. If Mercedes take the view that our optimal strategy is to have high enough peak power to achieve pole and then achieve the 4 PU limit via lower mode usage in races (benefiting also from lower weight) then this makes a lot of sense and explains to some extent relative competitiveness on Sat/Sun.

Likewise, if Ferrari, in the position of challenger, feel the best way to put pressure on their previously dominant opponent is to create a powerful unit that can run at higher modes for longer - with a stretch objective of meeting the 4 PU rule - this is also logical and goes some way to explaining failures late in the year.

So personally I see nothing in these figures that seems suspicious - acknowledging that since these are averages, if you looked at Brazil only it may have closed up somewhat - rather I think it provides some rationale to things like Haas claiming the Ferrari PU is more powerful despite evidence to contrary on power-dependant circuits (the Mercedes has more places to go when it needs to - e.g. they stick more fuel in at Monza, knowing they’ll have to compensate by running th engine lower elsewhere, like Malaysia).

[etusch]

That figure including sauber one? So the Ferrari unit maybe the strongest in outright power, but need to turn down severely at some point of race. While merc turn it down most of races? So the Ferrari and Mercedes rivalry this season is bullshit, merc is sandbagging RBR is the most efficient chasis out there, so the number seems right

Even accounting for Sauber, the Ferrari figure doesn't look right, being barely ahead of Honda.

Andy Cowel had said Honda will be good soon. What I understand from his statement is this mgu-h architecture has an advantage of being more efficient.

[OO7]

I don’t know how the majority on here (other than those with inside knowledge) can have much basis for what *looks right*.

We have reasonable data (Q3 performance, straight line speeds) to assume that the Ferrari is relatively close to the Mercedes in terms of peak power but little to go on that tells us anything about efficiency and, perhaps more importantly, strategy.

Because this is also about tactics for how you choose to go racing and how you want to achieve longevity from your PU. If Mercedes take the view that our optimal strategy is to have high enough peak power to achieve pole and then achieve the 4 PU limit via lower mode usage in races (benefiting also from lower weight) then this makes a lot of sense and explains to some extent relative competitiveness on Sat/Sun.

Likewise, if Ferrari, in the position of challenger, feel the best way to put pressure on their previously dominant opponent is to create a powerful unit that can run at higher modes for longer - with a stretch objective of meeting the 4 PU rule - this is also logical and goes some way to explaining failures late in the year.

So personally I see nothing in these figures that seems suspicious - acknowledging that since these are averages, if you looked at Brazil only it may have closed up somewhat - rather I think it provides some rationale to things like Haas claiming the Ferrari PU is more powerful despite evidence to contrary on power-dependant circuits (the Mercedes has more places to go when it needs to - e.g. they stick more fuel in at Monza, knowing they’ll have to compensate by running th engine lower elsewhere, like Malaysia).

You start by saying that you don't know how the majority without inside knowledge can have a basis for what looks right, then proceed to detail the opposite. I think there is enough information out there from qualification sessions and the races to form a good basis.

If Mercedes is running less race fuel they will suffer with less average power and this should be visible in the top speed traces. While the teams vary strategy and deployment, I doubt the differences (particularly between Ferrari and Mercedes) would be as high as 10% average.