About the same as rainman ^^ but I rarely get under 30 MPG per 450-500 mile tankful.
I fill to the same level, rarely fill until it's near empty and use paper/pen almost every tankful.

I used the inst mpg to learn how to drive it most efficiently for the first couple of months.
Now I just keep it on avg mpg and flip through every once in a while to make sure everything's ok.

I went on a cruise in NH with about 300 other sports & musclecars a couple of weeks ago.
Lots of 100+ passing romps, mostly 75-85 on the highway, lots of mountains, keeping up/down speed with the pack, etc...
Only about 140 miles of relaxed 65-70 MPH cruising on the way up/back.

I filled it before I left and refilled at about 460 miles on the way back.

I got 28 MPG on that tank

 

need to note what gas he's running. i've picked up around 4 mpg in 1 tank full of swapping from regular (87) to premium (93) gas

 

My dashboard mpg with my 5-speed is 29.6 driving to work and back. (no highway driving). With pen and paper I get 30.5 almost every tank.

 

it also depends on stop lights and signs. check your mileage on the highway. then reset and check it thru the city. sit at a couple of long lights and it kills your mileage.

 

Ty all for the responses! My first tank full of 93 I put in Saturday. Im running A/T. Wife said its up to 19.4 avg now. Thats better, I think I just got to get used to having a instant & avg readout. This is the cars 2nd tank of gas now has 384 on the clock. {Filled from 1/4 tank left} Dont think dealership put in 93 since I just yet dont have the stage-1. But will keep running 93 from here on out. ill have to get used to the characteristics of the car. Absolutely love it in any case! Now to find a good clear stretch of road and try a 0-140 lol
I did log some numbers of cam angle, spark advance etc to gauge if could be any problems in the future. But those may even change with Stage-1. I think I hit 15lbs of boost last night from a 60-100 run. So that seems fine. Has anyone messed with shift points on the car with A/T? Looks interesting LOL With the performance driving, and as a street rod we LOVE everything about this car!

 

25K miles on my SS.

Just drove from Milwaukee, WI to Omaha, NE and back. 29.1 MPG AVG That's HWY, City, HWY, etc, etc.

AC on the whole time!

 

I got over 30 MPG on my trip to Pittsburgh running between 70-75 MPH the whole way.

 

My last tank was 24.8 (figured by hand), mostly puttering around town. Last highway trip averaged 29.6 running 75 - 80. As mentioned it will get better after a few thousand miles.

 

22.9 around town. I don't lay into it but I don't drive like a wimp either. 30 hwy only and @ 25 mixed. I have almost 14K on an '08 and run 93 octane.
And when I stop on it, it reads 4 instant mpg! woohoo!
Beats my Jeep that gets 12-14 and is sitting in the shop for "lazy lifters" with 60K on the clock.
JIm

 

23.8 on my last tank... Mostly around town driving.

That's still over double what my previous DD got, and 9mpg better then my wife's SRX