I put a 96' 305 vortec motor in my 88' truck and ran a vortec carb intake with an adaptor. This motor has no EGR, smog pump, or catalytic converter. The motor runs strong and most people don't believe me when I tell them it is a 305. The only problem I have with the motor is it wants to stumble off idle and will pop through the TBI. Sometimes I am able to change my throttle position and it will take off. Other time it will act as though it is running out of gas and it will very rarely stall on me. I have the EGR solenoid still hooked up and I have the O2 sensor in the Y-pipe. I replaced every sensor on the motor, new fuel pump and filter. Changed throttle bodies. I had a 350 throttle body on it and changed to a 305. The best combination I have run is a 305 throttle body with a 350 computer. I have the timming at about 6-8 degrees advanced, if I go any more it will ping, if I go any less it will act worse. I have not received a code from my computer. I have herd many things please let me know what you think. I have herd that the vortec cam is too big. The plenum space under the throttle body is too big. The EGR is not there. And the O2 sensor is in the Y-pipe not in the manifold. I have put the truck on a scaner before and everything seems to be working fine. I do not understand all of this programing stuff. I would like to reprogram it myself but what would I need and how much would it caust for me to do it?
Thank you very much for your help and your advice.

 

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