Just bored over to 306 flat top piston higher compression not sure exactly what it is with comp cams 270xehr camshaft with comp cam lifters stock pushrods crane cam timing chain and gears
1994 mustang gt
just put on these parts
afr 185 pedastal mount heads
aeromotive fuel kit with rails ,adj regulator, 255l/h fuel pump,24lb/hr injectors
c & l 76mm intake with mass air sensor
bbk 70mm throttle body and underdrive pulleys
smog pump delete
trick flow street heat intake manifold
Crane Energizer Pedestal Mount Roller Rocker Arms 1.7 ratio
mac long tube headers with mac o/r h pype
dynomax superflow mufflers
msd super conductor plug wires, msd distributor

anyways just put all that stuff on compression is now probably even higher with those heads on but its turning over really slow so probably need a high torque starter but i will turn it over and tap the gas until it start running then it will run but i have to keep revving it or it will die. timing out but don't think that the prob and its running real rich once its going and start to backfire and shoot flames . once you take your foot off the peddle it dies so can anyone give me any help or comments plz and thanks just been wanted to drive my pride and joy for i don't know how long

sensors messed maybe tps or ? put on new egr and idle air control valve maybe sample tube is wrong size in intake for injectors

 

Timing. If it is done right it will not shoot flames. Not out the intake or exhaust. Which way it is backfiring you didn't say but one way or another it sounds like you are a tooth or 2 off.

 

you need to set timing , have fuel pressure properly adjusted and perform base idle reset