My engine keeps stuttering and dying while im driving?

ok i have just installed a new chevy 409 stroker into my 83 k5 blazer it was completly rebuilt and so far has been doing excellent. it is automatic and carbuerated. well for the past three weeks il be driving down the road and all of a sudden it will kind stutter and then die on me.. il start it back up go a little ways and then it'l do it again and then again, after the third time it wont start at all. i have replaced the battery changed the ground so it is straight to the frame, i have the engine ground to the firewall and to the frame, iv gone through the wiring and nothing seems outta place or exposed to bad ground so i have no idea, could it be in the ignition or in the choke on the carb?