F1 Engineer on Reddit right now

[Pandamasque]

This question gave him up: he works for McLaren.

Not any more

[Raptor22]

the new engine formula from 2013 onward is for 1.6L 4cyclinder 4stroke turbo engines with Gasoline direct injection.
For a 4cylinder engine running GDI making 12,000rpm will be quite a challenge due to the harmonics of a 4 cyclinder.
Way back in the 80's the BMW 4 cyclinder turbo in the Brabham did not reach 10,500rpm or it would grenade. It ran massive boost pressure to achieve 1,500bhp in qualifying trim. the upper rev limit for a 4 cyclinder is around 12,000rpm. Beyond that their livespan is measured in seconds.

[volarchico]

the new engine formula from 2013 onward is for 1.6L 4cyclinder 4stroke turbo engines with Gasoline direct injection.
For a 4cylinder engine running GDI making 12,000rpm will be quite a challenge due to the harmonics of a 4 cyclinder.
Way back in the 80's the BMW 4 cyclinder turbo in the Brabham did not reach 10,500rpm or it would grenade. It ran massive boost pressure to achieve 1,500bhp in qualifying trim. the upper rev limit for a 4 cyclinder is around 12,000rpm. Beyond that their livespan is measured in seconds.

This might be way off base, but the original Honda S2000 managed to run a 9,000 rpm 2L inline-4 and their design life for the engine was definitely longer than 5 race-lengths!

[Formula None]

@raptor22, you're probably aware already: Moto GP I4's (800cc) rev'd to 17-18k. Surely 12k won't be an issue? Can you clarify? Unless GDI complicates things, which you seemed to be implying, not sure. Kawasaki's production 1.4L I4 in the ZX14 redlines around 11,000.

[noname]

Well, at least now we know that in 2013 teams will try to get more RPMs from their engines. Apparently it will be hard to reach the 12000 rpm maximum that the engine must deliver.

Teams we are talking to are giving us much lower numbers.
12k RPMs was not even mentioned.

[Raptor22]

Its a capacity constraint. the bigger the 4C, the lower the practical rpm.
GDi does complicate things somewhat but not majorly.
Another thing to consider is that a motorcycle engine doe snot have a very useful powerband and the pistons are designed to be as light as possible since overall vehcile mass is low.

Volarchico, any 2.0L 4 will rev to around 9,000to 10,500 rpm and have a useful life. Take them higher and they will start to fallapart due to 2nd order vibrations due to the firing order and other mechanical constraints.
Lighter engines i.e. the motorcycle example, can run heavier balance shafts but how often are they running at full rpm?
Add in a turbo to increase the BMEP and its harder still to reach high Rpm due to the higher combustion pressure remember the piston in a turbo charged engine is heavier than in a normally aspirated engine due to higher combustion temperature and pressure.
Add in 2nd order vibrations, balance shaft weight and you end up with a practical limit ofless than 12,000rpm.

[Raptor22]

@raptor22, you're probably aware already: Moto GP I4's (800cc) rev'd to 17-18k. Surely 12k won't be an issue? Can you clarify? Unless GDI complicates things, which you seemed to be implying, not sure. Kawasaki's production 1.4L I4 in the ZX14 redlines around 11,000.

YOu and you will notice that the bigger the engine the lower the max rpm...
Which I believe is what I have said.
So for a 1.6L T GDI you're looking at a max practical rpm probably around 10,500 to 11,000.
They can probably squeeze a few hundred more out of lightweight turbo or dropping boost pressureon intake stroke or some other trickery.