My first thought is the air/fuel ratio is for fuel vapor n air, not liquid fuel, so you have to compensate for the difference in gas/vapor volume at operating temperature and pressure vs. liquid volume. In other words, 1 L of liquid, when evaporated, would yield more than 1 L vapor at standard pressure.
Thank you for the clarification and your hard work! Like others I prefer compact (strongly), so I’ve rolled back to 0.6 for now but will check back once it’s available in 1.0.