Hello, I had my 74 SB Chevy 4X4 converted with a 2015 LS crate motor. the install seems good, very much OEM I think. my problem is that I'm only getting about 5-7 MPG! took it to Rydell Chevy, they seem clueless... need help or referral for a person who can correct, special tuner?... spent lots of $$ but not to get 5-7 MPG. thoughts? Tim is so. cal

 

You're in the wrong section. You might want to try the conversion section or one of the other tech sections. This section doesn't get much traffic as it is dedicated to staff builds. As far as why you're getting such shitty mileage, have you checked the obvious things like fuel filter? Did you wire up the O2 sensors? What transmission are you running? Obviously a transmission with more gears will get better mileage.