hey guys i have a gm 350/290 crate engine with a 700 cfm edelbrock performer series model 1406 carb, stock jets and rods. the engine idles like a champ. when im driving as soon as the engine warms up if i tke it easy on the throttle its fine but if i kick it in the ass (like to pass) she starts backfiring and i can feel the power surging. ne one know ne possible causes?? timing is right on.. the only thing i can think of is its a ignition problem or i need to rejet the carb.. ne ideas/experiances?? thanks for lookin!