Quote:
Originally Posted by pgfpro
Enjoying the write up!!!
Sounds like your engine likes the extra overlap?
So is the ecu resetting itself??? Also is the A and B tables min octane, and high octane tables, based on low knock logs?
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I imagine when there's 2 tables A and B that generally does refer to something like that, or maybe a normal and limp-home mode. I have no knock registered though, since my fuel has so much ethanol in it
(on that note, one of the few E85 stations in the Bay Area is on the way home from work, conveniently).
It seems like fueling compensation target is more like a closed loop AFR fluctuation allowance meant for calibrating the fuel trims, since the AFRs are just all over the place at cruise now. I'm going to revert those tables and see how much O2 sensor scaling the engine will tolerate.
And I don't think the engine "likes" overlap, it can just take more of it
You can find the development papers for the IS350's 2GR-FSE engine which mention how the new direct injection system allows 21% charge dilution with internal EGR, 2x as much as the MPFI engine. I'm going to revert the exhaust VVT maps and keep the intake retarded to -10 and see what that does. If it doesn't cause an increase in vacuum I'll keep that because less charge dilution is better for combustion. It is however possible that it'll increase vacuum because during overlap the higher pressure in the exhaust system can cause extra exhaust to blow into the intake tract, vs. just trapping more exhaust in the cylinder at the beginning of the intake stroke.