ok so first off the car is a 305 tpi with a 350 chip headers and completely stock otherwise. the car runs good a part throttle and at cruisin its nearly good but it has a lil stumble every 30 seconds or so. under half to full throttle it spark knocks hesitates bad and if i hold into it it starts to smooth out but it takes a couple seconds. yes i no it already runs lean because of the chip bt it does it bad bad now. so far iv checked and set the timing rite and put a new fuel filter on anyone with some ideas it would b appreciated.

 

Should be running rich with the 350 chip in open loop...... what's fuel pressure look like?

 

well its got the 350 chip with 19lb injectors and im gonna get the fuel pressure guage later today