bergie88 wrote:godlameroso wrote:bergie88 wrote:
Seriously? A normal turbo engine without a MGU-H the turbine would be sized to efficiently produce the required power for the compressor to produce the required boost for the fuel flow. The rest of the exhaust is sent through the waste gate. To efficiently harvest energy for the MGU-H you will require a bigger turbine to make use of all the exhaust gases. This doesn't effect the compressor in any way at all as the fuel flow is fixed and so the boost required for it. As such to extract more energy for the MGU-H you require a large turbine Not a larger compressor.
Therefore Ferrari's problem last year of not being able to get enough energy from the MGU-H come down to having a too small turbine and has nothing to do with the size of the compressor.
You could have ultra lean running if you design your combustion chambers, and DI system to have a type of stratified charge, so you can burn at or a little bit above stochiometric in part of the chamber, as long as you can control and precisely burn fuel at the right amount, and introduce boost pressure without making the overall AF mixture too lean, I don't see the downside to running as much boost pressure as possible given the PU configuration.
Maybe knock is a problem?
Again it all depends on the fuel you're using, and how your combustion concept works. If you have no pre-chamber and just straight up DI fuel with air charge you're 101% correct, knock is a big problem. But if you design your chamber in a certain way you can run very lean without knocking because the fuel is being burned at the correct ratio in the pre-chamber and the flame front expands into the main chamber, so although the overall charge that is acting on the piston is rather lean, combustion itself is at or near stochiometric.
