I think that theres a reason that this system wouldn work too well. Remember, gm TBI style fuel injection is based on the o2 sensor and the crankshaft sensor. System runs rich, leans back the injectors, system runs lean, richens it out. Now, with one set of injectors there is an even draw from the set. However, with a dual set there is now 2 injectors per cylinder, each one covering 2 clyinders. As such, when the system registers a rich code, there is now two seperate systems to lean. But, if the engine has one set running correctly and one spraying too much, there is no way to compensate. Same applies if it is too lean. Simply put, "too many chefs ruin a soup" Were you to actually run this type of system, the best bet would be to run two independant manifolds for each se of injectors. Then run your O2 sensor for two cylinders on each bank. In effect, this would have the EFI setup of two V4s but the power, ignition and fuel economy of a V8. If Anyone follows me