Civics are even worse than Accords for sound proofing.....that's just something I've never known Honda to do a great job with.
I shift 2.5-3 during normal driving, even with A/C running. I try to conserve gas a little, although the problem with that is that I start out at ~2 in the new gear, so I've got no pickup......gotta remember not to hammer the pedal to go anywhere, otherwise I piss out gas and still don't accelerate.
I'd say shift where you feel like shifting.....I don't really pay any attention to my tach anymore unless I'm planning on hitting redline, then I watch it pretty well.
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