I would guess it is the gearing in the SI being for better 0-60mph time. More sporty and also tuned for more hp than the other Civic models and trims. You would need to compare 2023 SI mpg to a 2022/2021/2020/2019/2018 year model.
Sure, understandable but I'm really taking it really easy since it's still in break in period.
Can't wait how it'll change after 1K miles.
Handling wise is outstanding. That much I can tell.
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