Quote:
Originally Posted by steve99
yeah for sure you can run more or less port especualliy at lower rpm/loads.
but above say 5000 higher loads the port to di seems to get max fue flow round the 35% port 65 di, on petrol at lower boost you got more options but on e85 the 35% port or arround that seems to balance the two systems reasnobly well
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Well just to put into perspective, I had no fuelling issues on pump fuel with the Sprintex at less than 20% PI ratio at max RPM. I can understand if you want a blanket setting to be able to run E85 without having to reconfigure maps, but there is not enough airflow through a Sprintex to have to run more than that. I've actually used the facelift PI Ratio maps as a basis as they run more PI through the midrange and found that helps.
Remember general rule of thumb is that more DI ratio will require more advance for similar power, I expect this is down to poorer mixture in the cylinder, but it does give extra cooling so will allow you to run harder more consistently. You want the best balance and I believe that when they recalibrated the tunes for the facelift, this is something that they had determined over the life of the car. Also, there is no part of the map when the PIs suddenly switch on, like on the original maps, so you get smoother fuelling as a result. Without a dyno, I don't imagine there is going to be a large difference - but I wouldn't go straying too far from OEM without good reason.