Honda Power Unit Hardware & Software

[Singabule]

Piston speed.....

Aside from weak rods I still don't see how one overrev would damage the bottom end.

Vibration could destroy bottom end easily, as the load could higher than anticipated by design. This vibration occur at certain speed, and could be devastating, as in renault first turbo era. Even with pneumatic valve, the engine could not cope the load and boost more than 13000 rpm. Remember that engine has very larger B to S ratio, compared to honda and Ferrari engine. This vibration shaken loose all nuts and seals and lead to catastrophic engine failure. On the other hand, spec 2 honda engine is prone to lower rpm, and they afraid high rpm too since it is not designed to be operated on that high rpm

[diffuser]

Could be just BS so they can use it at the next race without a penalty....

[ArcticWolfie]

Both Hondas survived the Baku strain even heard Alonso reached 350,1kph @ finish line speed trap probably a tow + DRS but still.. seems Honda is really getting on it now.
Renault had 3 engine failures this race (I'm a Verstappen fan)

[j.yank]

Looking at the speed trap and maximum speeds in all sectors, are we sure that Alonso didn't run the updated PU after all?

[RedNEO]

Looking at the speed trap and maximum speeds in all sectors, are we sure that Alonso didn't run the updated PU after all?

Slipstream/double slipstream mate nothing to do with the lack of power.

[ZakB]

Looking at the speed trap and maximum speeds in all sectors, are we sure that Alonso didn't run the updated PU after all?

They also changed their downforce levels on Saturday.

[wuzak]

Remember that engine has very larger B to S ratio, compared to honda and Ferrari engine.

Bore to stroke ratio mus be the same, within a small tolerance.

The capacity must be 1600cc +/-10cc and the bore must be 80mm +/-0.1mm.

So the bore:stroke ratio must be between 20.15 and 19.85. Or 20 +/-0.75%

[PlatinumZealot]

Hmm i can imagine everyone is at 1610cc with a bigger stroke.

[gruntguru]

This new "spec" is not 3.0. That is still further down the road. Think more of spec 2.2, 2.5 that was in Alonso's car. As far as not running the current PU, it needs to be examined before further running. When the gearbox let go, it severely over-revved the PU so it should not be run this weekend without potential damage analysis.

Severely over-revved? Not according to my source!

Agreed. Unless the "transmission failure" selected a lower gear, the engine will not exceed 15k rpm - even when suddenly unloaded at max power.

[gruntguru]

Hmm i can imagine everyone is at 1610cc with a bigger stroke.

Or 1590cc?

[wuzak]

Hmm i can imagine everyone is at 1610cc with a bigger stroke.

Or 1590cc?

I don't know about that, but some allowance must be made for bore wear?

[PlatinumZealot]

Bore wear.. Ok let us work it from that angle.
If you have a 80mm bore and stroke of 53.25mm the displacement is 1606 cc
If the bores wear to 80.1mm the legal limit.. The displacement increases to 1609.99 cc... Within the legal limits.

This is assuming bore wear is typically 0.1mm. On the other hand.. Wazari coyly said 1590cc without saying why.. But if he meant for wear then we can sorta estimate that the bore wear is as high as 0.5mm in all cylinders.

Sounds ok?

[godlameroso]

If they use they type of coating I think they use, bore wear should be fractions of a mm in the ICE's life cycle.

Maybe 1590 to have the shortest possible crank throw, and trying to increase dwell time with longer rods.

[gruntguru]

I said "1590cc" because I believe best power under this formula would be obtained with a smaller engine. The rules allow +- 10cc so 1590 it is. As for Bore/Stroke, the teams would also aim for the bore limit that gives best power - I would think smaller ie 79.9 mm. Of course we are talking about miniscule gains here - perhaps 1 or 2 hp.

[Singabule]

Remember that engine has very larger B to S ratio, compared to honda and Ferrari engine.

Bore to stroke ratio mus be the same, within a small tolerance.

The capacity must be 1600cc +/-10cc and the bore must be 80mm +/-0.1mm.

So the bore:stroke ratio must be between 20.15 and 19.85. Or 20 +/-0.75%

First turbo era of 80's. Sorry for confussion