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Could an engine experience knock if there's no fuel film left in the intake port?
If so would errors in port fuel film calibration be further provoked by increased ignition timing?
Otherwise, what are the consequence of inaccurate fuel film / transient fuel calibration?
BACKSTROY: I built a Gen III Small Block Chevy. Specifically it's a 6.0L LQ9 baseline with upgraded valvetrain. Since building it I've never been able to run anything reliably w/o knock beyond the low octane spark map. When I advance timing towards high octane table I observe the following:
- Verified real knock (not false).
- Random From the perspective of airmass and or RPM.
- Better correlated with transient airmass conditions specifically increases in load.
- If I'm extremely light on the throttle, only slow changes in throttle position (load), I can operate in the same load & RPM w/o observing knock.
- The wideband closely tracks the commanded AFR with very little overshoot or lag but not sure if that tells me much of about the state of port fuel film.
ENGINE BUILD NOTES: https://matthewjeschke.com/gen3sbcbuild
Found this post on topic. Read and reviewed my logs: https://forum.hptuners.com/showthread.php?44912-Transient-Fuel-Tips-Tricks-and-Info-A-how-to-guide&highlight=fuel+film
