Newbie here. I have a 87 K5 with 350 and 700R4. I recently installed a new engine and added a Holley Projection Intake, Holley replacement TBI and Edelbrock shorty headers. I was told by the vendor that the intake and TBI would work. Removed and plugged EGR, left EGR controller connected to harness. I also removed the AIR pump and related equipment, did purchase headers with AIR provisions. The old engine ran fine (just smoked a lot) Problems: New engine runs poorly, with the coolant sensor plugged in, the engine has no power and backfires through the TBI when accelerating under load and surges at idle. With coolant sensor disconnected, better but not great power and no backfiring. I assume the EGR is the culprit, the reason it was removed is because it takes an 86 or older valve, plus the valve interferes with the IAC. Can and how do I make it work without an EGR, the vehicle resides in an area where emission testing is not required. If I must have an EGR, what can I run, I need one with a smaller head. (Did replace the O2 and coolant sensors, not the MAP) Or, is the intake manifold the culprit, I did keep the old one, not excited about replacing. Sorry for the long post and thanks in advance for help. I am used to working on classic cars, simple to say the least.