On the air induction tube on an LS engine one CANNOT have more than one bend. Didn't like the looks of the cone shaped filter being crammed into the front corner between radiator and inner fender as well as leaving no horn room so curved the tube back over valve cover, much prettier. We switched mass air flow sensor and accelerator pedal with those from a perfect running Olds with identical engine and the Olds still ran perfect with the switched parts while the AD still ran like crap with it's new parts. Fuel fine, electrical fine, everything checked out. Finally sunk in our thick heads the only change made was going to the "pretty" induction tube. Cut second curve off and it purrs. Never had this problem with a Rochester one barrel. First pic is a test run with a single curve tube (ran fine) and second is the pretty tube witch gave a sick running engine. We are still learning.