How bad is it?

 

383 + 3.73 gears + 3500 rpm stall + large cam with lots of overlap = 8-10 mpg.

 

It's going to depend on many things. The tune, gears, cam ect. My 95 Z has a 383 with 3.73's and a mild cam, with a superior tune from PCM's for less. Granted it is a 6-speed but I still average about 21 mpg. The worst I have ever got, was about 15 and that was pretty much railing on it constantly from Full to Empty. On extended road trips on the highway I have gotten as good as 24 mpg.

 

i was in the 14-15 range, hotcam 2000 stall. rich tune.

 

20-21 mpg regular! As previously stated it depends on various things,your right foot,tuning, cam, driving conditions and terrain (hills or straight driving,curves). My route is down a 28 mile straight hill going to work and up returning home with little curves until I get into town.

 

9 mpg 3:91 gears 2800 stall stroker w/le2 h/c madz28 tune