I am building a motor for my 88 GMC k5 Jimmy. I am building a 383 with 6.0 inch rods and 383 hypertec flat tops, stock tbi heads( I plan on upgrading later just can't afford any right now), 270 adv. dur. cam with .495 int. lift/dur @ .050 .218 degrees- .502 ext.lift/dur @ .050 .224- lobe speration is going to be 108. this is a hydrolic roller cam. I want to keep my TBI but i need a chip to run with this setup. I would like to have the egr removed from the computer because it is no longer on the engine. From my understanding the egr will make the engine run lean at normal crusing speed. I will be using headers as well so do the O2 sensors need be removed to be an open loop system like a marine engine, or would it perform better with O2 sensors? I had one guy tell me that the tbi want run at all with that lobe seperation because of vacuum, and he could not burn a chip for it. Another guy said that he can't burn a chip for my application through the mail. I know I can't be the only person that has built an engine with this set up. If it had to be ran like a marine engine that does not use a map sensor or O2 sensors that would be fine. I want the throttle body for crawling where a carb will fail. Can any one help me on this matter. Thanks for any info on this, it is hard to find anyone who knows anything about fuel ingection. I feel like their is some one on this site that has tackled this before me.