Honda Power Unit Hardware & Software

[godlameroso]

Does this mean different lift and duration for each intake and exhaust valve? Are these head channels supposed to act as variable ports? That's very clever, I'm impressed if so.

[roon]

Does this mean different lift and duration for each intake and exhaust valve? Are these head channels supposed to act as variable ports? That's very clever, I'm impressed if so.

Yeah, might be a reference to asymmetrical camshaft lobes. I'm not sure what this would have to do with "complex" ports, though.

[godlameroso]

Does this mean different lift and duration for each intake and exhaust valve? Are these head channels supposed to act as variable ports? That's very clever, I'm impressed if so.

Yeah, might be a reference to asymmetrical camshaft lobes. I'm not sure what this would have to do with "complex" ports, though.

Since there's no variable cam timing or lift then with unique cam profiles and variable ports maybe you could get the effect indirectly.

[PlatinumZealot]

Does this mean different lift and duration for each intake and exhaust valve? Are these head channels supposed to act as variable ports? That's very clever, I'm impressed if so.

Yeah, might be a reference to asymmetrical camshaft lobes. I'm not sure what this would have to do with "complex" ports, though.

I think he means the axis and movement of the valves is not perpendicular to the axis of the camshaft and also not paralell to its sister valve.
In other words, the valves are splayed out wide to give some sort of desired flow pattern into the cylinders. Special cam followers would need to be used if this is true and the cylinder head would indeed be slightly taller maybe 1cm taller...?

[63l8qrrfy6]

Does this mean different lift and duration for each intake and exhaust valve? Are these head channels supposed to act as variable ports? That's very clever, I'm impressed if so.

Yeah, might be a reference to asymmetrical camshaft lobes. I'm not sure what this would have to do with "complex" ports, though.

I think he means the axis and movement of the valves is not perpendicular to the axis of the camshaft and also not paralell to its sister valve.
In other words, the valves are splayed out wide to give some sort of desired flow pattern into the cylinders. Special cam followers would need to be used if this is true and the cylinder head would indeed be slightly taller maybe 1cm taller...?

Correct - the pad on the finger follower is ground with a '3D' surface profile to maintain the desired contact with the valve end. They've been doing this ever since compound angles became the norm.

[63l8qrrfy6]

"Tanol" = butanol.
Oil tank issue was attributed to shape, PU location and mounting angles. This led to intermittent cavitation causing air to go into the supply line for the MGU-H. Slosh dynamics is very difficult to mimic.
Camshaft design is part witchcraft and voodoo. This version of camshaft is slightly unique due to a very complex intake and exhaust passages in the cylinder head. One reason for a slightly taller and heavier head. Point to ponder: think BMW motorcycle engine camshafts.
I hear dyno testing to date is no comparison to same time last year. Both in terms of power and reliability.

Would the main/big end bearings not have failed first? Or is there a split oil circuit with multiple oil pumps ?

Normally cavitation on its own doesn't cause air in the oil system as vapor bubbles collapse very fast.

[Wouter]

I hear dyno testing to date is no comparison to same time last year. Both in terms of power and reliability.

That was also the situation in Abu Dhabi. I was hoping anyone could tell me if they made progress during this wintertime in terms of power and reliability. Nevertheless thank you for answer Wazari.

[OO7]

Since there's no variable cam timing or lift then with unique cam profiles and variable ports maybe you could get the effect indirectly.

Sounds expensive.

[carisi2k]

Is that dyno testing good power and reliability wazari or not so good and what about economy? Will the Honda be using less fuel to go with this extra power and reliability?

[hurril]

Dear Mr. Wazari,

if you could change something (or a few things) in the PU rules, what would it (or they) be? Freevalves? Port injector too? Two turbos?

[Nonserviam85]

Point to ponder: think BMW motorcycle engine camshafts.

Wazari, do you refer to the 1200cc boxer camshafts? The ones with the conical profile and ~20deg valve angle?

[Lucky]

Already the opening specification power unit in 2018 has almost completed the specification and it should not think that results will come out soon. Asaki himself said "I want time and I want about half a year."

https://translate.google.it/translate?s ... t=&act=url

[Snorked]

We need a proper translation; is the author of the article saying the opening spec of the engine (which was Hasegawa's ?) is almost complete and won't see the results of Asaki's input, who says he needs 4, 5 or 6 months to implement it?


A new issue of that F1 Sokuho magazine releases on the 25th so maybe we'll get a full interview with the new Honda staff as that photo looks like some press junket setup.

[dmjunqueira]

Point to ponder: think BMW motorcycle engine camshafts.

Wazari, do you refer to the 1200cc boxer camshafts? The ones with the conical profile and ~20deg valve angle?

http://articles.sae.org/8444/

[roon]

Conical lobes aren't unique to BMW. Look at Brian.G's threads on this forum. I'm not sure this is the valve detail he's referring to.

BMW had asymmetrical cam lobes at one time. Asymmetrical in the sense of timing i.e. indexing of the lobe apexes relative to each other. However, this may also not be unique to BMW.





Keep in mind the "complex" runner reference. It could be that, due to runner shape, a follower or rocker is used on one of the valves which contacts the camshaft at an atypical location i.e. not beneath the camshaft, but at the side or top. If there was no space available directly beneath the camshaft for a traditional bucket and spring arrangement, due to runner shape, such components could be relocated to the side of, or on top of, the camshaft. This would require 'asymmetrical' or out-of-phase lobes.

Another interpretation may be rocker arms, generally. Both valves operated by rockers; no asymmetry. BMW have used cam operated rockers on motorcycle heads before. Again, not unique to them.







This potentially frees up space underneath the camshafts and can permit greater valve inclination angles. There is precedent elsewhere:

Injectors on the exhaust side is nothing strange. The injector merely sits on the cylinderbank together with the exhaust valves instead of with the intake valves.

I always thought that the injector is placed in the top of prechamber, but If injector is in exhaust side (as motor fan pic. indicates) how do they have rich mixture in the prechamber? there might be multiple injection first one when piston is near tdc to mainly fill prechamber?
https://drive.google.com/open?id=1tpCUl ... SY3ZJV5gNa

I know, right? I've wondered that from the start and the only thing that seems possible is for the injector to create a denser cloud close to the holes in the pre-chamber and then hope that enough of it gets sucked/ pushed in there by the compression. (The pressure gradient is evened out/ lowered so that it is equal on both sides of the "membrane" that the holes form, thereby pulling the fuel with it.)

There seem to be so many concurrently active factors that go in to this though and it's not that easy to form a working picture of all of them I think.

The piston crown could either partially form the prechamber or contain an internal passage that aligns with the injector at TDC. Either way, the injector would spray into the piston/combustion chamber prior to TDC. At and near TDC, the piston geometry ensures that only a small volume is available for the injector to spray into: the prechamber.