Rebuild 1971 small.block 318LA with all new: Edelbrock 1406, Edelbrock rpm intake, new Promaxx aluminum heads & Lunati Voodoo hydraulic roller cam. Msd 6a, Msd distributor, Blaster 2 coil, msd spark plugs / wires. Issue is engine has a misfire or like a lean burn on one cylinder. Kinda goes away at idle when I adjust air/fuel screw a half turn richer on the passenger side. The other 2 cylinders run richer so that is just not a fix. Check ohms on coil & plug wires with meter both good. Can lightly feel the misfire at cruising speeds. Changed out carb springs from the lowest blue up to pink. Im in the idle circuit because mixer screws adjust. This is the 4th intake gasket replacement due too other issues but always been like that. Any ideas?