This can't be right
 

I just got a 2010 Civic EX Coupe and I haven't had a chance to run a full tank through it yet to check pump vs SGII but I just did my best trip (per my SGII) since I got it last Monday. This was 45 miles from Exton, PA to Deptford, NJ via RT 202 > 76 > 42.

Mods:

Tire pressure @ 44psi
a really really light foot on the gas

So light that my foot is actually killing me from keeping the pedal just barely pressed. I try to keep my TPS reading under 18 at all times even if that means accelerating slower. I manage to keep it in 5th (this is an auto) as much as possible with the techniques I've read on this forum and others. My speed is correct on my speedometer, SGII and confirmed via GPS.

And this is the result.. which honestly I can't believe is correct. I have my fuel cut off set to 16 (idle = 12 + 4 per manual) and engine set to 1.8 liters, everything else set to defaults. 52.4 MPG. I have a photo of my SG but I can't post it until I hit 5.

Is there any way possible this is actually correct?

I would think so. All highway? Yeah. I regularly break 50 MPG on my highway trips. Your SG might be a little optimistic before you get it calibrated, but I don't think it's that far off.

Congratulations, by the way.

It's pretty much all highway, but some traffic that called for a few stops. I maybe did a total of 2 miles in neutral coasting with the engine on. My old car (2005 Si) was pretty close to accurate and I never calibrated it. I just really can't believe it. It's a lot better than the 29 or so I'd get when I really tried with that car. BTW the car has 12.5K miles on it.

Sounds pretty reasonable to me. Obviously you'll want to double-check when you fill up, but I would expect numbers like that on an easy highway trip.

I love this thread. Seems like most with a title like this one's go more along the lines of "I can't believe this car is getting such terrible mileage... what's wrong??"

Nice to see someone surprised on the upside. Here's hoping the gauge is close to reality!