Thats freeking awsome. They should all come with 5.7's. I got the same milage with the cam in my truck too. Its a user friendly cam if you can just tune the damn thing.

My mpg screen says I was getting 20.3mpg going down past Freeport and back. I was only cruising at 67-68 though. I bet it drops fast any faster. It has enough grunt turning about 1800rpms at 68 that it doesnt have to downshift on hills. So far I've put 200 miles on just over a quarter tank, but I've driven nice too. Total combined town/highway with most of it town seems to stay around 17.5. In all it gets better than I expected and its got some good power off the line. You have to be real gentle with the gas taking off or it jumps on you.

 

When it loosens up after breaking in, it should get a little better mileage too.

I seem to recall a magazine article on a RCSB getting 23mpg with a STS.

 

Nice try, my 01' RCSB got over 24mpg stock. My 00' ECSB got 16.5 till I did the gears, heads, cam, and tuning and then it got 20 even.

I may look into a turbo setup in a year or two. First thing is milage, then Bling for tha bitches. Then once the warranty is out maybe a turbo. Hopefully by then I can find a cheap RCSB 4x4 with really high miles to build up.

 

My Tahoe gets 8mpg and its almost stock.

 

With my heavy foot....my RC averages 19.8....w/ a tune..CAI and Slowmasters.....but heavy *** wheels and a heavy cover too...im not bitchin..i drive like a bat out of hell..lol