Chevrolet Repair: 1983 z28 tbi c/f injection, vacuum lines, throttle bodies

Question
project car - car backfires thru throttle bodies (carbs) blowing off vacuum lines and will not crank. Is this a timing issue?  How to re-time vehicle when it will not crank or run?

Answer
HI JOHNNY,NO CARBURETORS,[FUEL INJ,THROTTLE BODY]CAN YOU GIVE ME A LITTLE MORE BACK GROUND ON THINGS ??? ANY TIME A ENGINE BACK FIRES IS USUALLY A IGNITION PROBLEM, BAD DIST-CAP,CROSSED  WIRES, ETC..THE TIMING COULD BE WAY OFF BUT WHY. HAVE YOU DONE ANY ENGINE WORK ON THIS ??? VALVES TO TIGHT ???YOU ALSO SAY THAT IT DOES NOT CRANK ??? HOW CAN THE ENG BACKFIRE IF IT WILL NOT CRANK ??? COME ON,, HELP ME OUT HERE !!!!! GET BACK TO ME WITH MORE INFO, IF POSSIBLE TOM....