Seems to be plenty of discussion of PI : DI ratio about but I thought this would be a good place to chime in on people's thoughts and if they have tried anything successfully. I think both NA and FI applications are worth a shot as there may be different benefits for each. I think there may be a more optimal map over the OEM for power, but I also get the impression that there are benefits to running PI at various stages of the rev range. I guess this will focus on WOT application as I doubt many will change the lower load regions but any discussion is welcome.
Below is a picture showing the OEM map in WOT load regions between 2-7.4k. Yellow is the % of Direct Injection, blue is Port Injection. As standard it is quite heavily biased toward DI but IMO there is a reason that the OEM decided to re-introduce the PI at higher RPM. There is definitely capacity to run more DI than that. It may be due to DI firing angles and open time requirements that a percentage of PI is required, as I have had previously hinted to me.
So is a higher % of PI at the very top end beneficial and allows you to run more timing? If you're running boost and aren't running as much timing, is more DI better at controlling knock? Discuss.....