Get used to it. My LT1 gets awful milage. Solution? I spent $900 on a 2002 civic. 35mpg all city driving. Only use the Camaro on weekends now. FWIW I usually get 150-180 miles mixed driving if I'm easy on the car...

 

Is your math correct?

On a all highway trip I can nock down 28 mpg and I have high miles.

 

Your hard cold starting issue can be caused by a bad fuel pressure regulator. The diaphram in it starts to leak a little and causes a condition similar to flooding. There should be a small hose going from the nipple on the end of the regulator (rear side of the intake between the fuel rails) to a nipple on the passenger side of the intake toward the rear. Pull that hose. If gas leaks out, or even if it has the smell of gas inside it, the fpr needs to be replaced.

 

I average 150-180 a tank as well like coolmanvette75 posted but seeing I work maybe 3 miles away. WOT a lot in my short trip and get stopped by stupid traffic lights. I don't expect much better. Now if I get on the freeway things are different. Buy a civic or something if gas mileage is a concern.

 

I got a question that fits right along in this thread. Same as OP here. My LT1 gets less mileage after i replaced a few things. Before i could get 200-210 miles a tank. My opti went out and i got the fuel pump / filter / opti / wires and plugs all replaced since i had it off the road and now shes alot peppier but now i get between 130-150 a tank. Any thoughts or ideas would be much appreciated

 

I found the mpg problem and the cold start problem. One of the wires to the maf was severed and I also have a problem with the esc circuit. I still pulled down 18.5 with those problems, so I should be in the 20s when that's fixed. I got 170 miles to a tank with bad o2s and hammering it every chance I got lol so I know it's capable of much more. Gas mileage is a concern but I already own 3 cars and live in a condo, so a moped or bike is the only other option and thats not happening